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Columbia  Umbergttp 
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College  of  ^fjpssician*  anb  burgeon* 

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APPLIED 
SURGICAL  ANATOMY 


KKUIOXALLY   PRESENTED 


FOR  THE  USE  OF  STUDENTS  AND  PRACTITIONERS 
OF  MEDICINE 


BY 

GEORGE   WOOLSEY,   A.B.,  M.D. 

PROFESSOR   OF   ANATOMY   AND    CLINICAL    SURGERY   IN  THE    CORNELL  UNIVERSITY   MEDICAL   COLLEGE 

BURGEON  TO   BELLEVUE   HOSPITAL,   ASSOCIATE   8URGEON   TO  THE   PRESBYTERIAN 

HOSPITAL,    FELLOW  OF  THE    AMERICAN   SURGICAL  ASSOCIATION 

AND    OF  THE    NEW  YORK   ACADEMY   OF   MEDICINE 


SECOND  EDITION 

ENLARGED  AND  THOROUGHLY   REVISED 


WITH   200  ILLUSTRATIONS,  INCLUDING   59    PLATES,  MOSTLY  COLORED 


LEA  &    FEBIG  EB 

a    FOB  K    \  \  I)    I'll  I  I.  \  DBLPHIA 

1908 


Entered  according  to  the  Act  of  Congress,  in  the  year  190S,  by 

LEA  &  FEBIGER 
In  the  Office  of  the  Librarian  of  Congress.      All  rights  reserved. 


PREFACE  TO  THE  SECOND  EDITION. 


In  the  Preface  to  the  original  issue  of  this  work  it  was  pointed  out 
that  the  study  of  Anatomy  is  relieved  of  much  of  its  difficulty  when  it 
is  approached  on  the  practical  side.  Isolated  details  do  not  appeal  to 
the  faculty  of  interest,  but  when  they  are  set  forth  in  their  natural 
relationship,  and  their  practical  application  is  shown,  the  mind  grasps 
and  recollects  them  with  facility.  As  Anatomy  is  the  most  basic  of  all 
the  medical  sciences,  a  working  knowledge  of  its  data  is  indispensable 
for  the  study  and  practice  of  scientific  medicine  and  surgery.  The 
author  has  endeavored  to  embody  these  principles  in  this  work,  and  to 
do  it  in  such  a  manner  as  to  answer  the  needs  of  both  students  and 
practitioners. 

The  plan  of  this  volume  has  been  developed  from  eighteen  years' 
experience  in  teaching  Anatomy.  The  author  believes  the  form  of 
presentation  he  has  followed  to  be  the  best  for  didactic  lectures,  and 
furthermore  that  Descriptive  Anatomy  is  most  advantageously  learned 
from  text-books  and  in  the  dissecting  room.  The  regional  and  topor 
graphical  method  of  treating  Applied  Anatomy  is  likewise  the  most 
convenient  for  clinical  purposes. 

It  is  scarcely  necessary  to  state  that  in  order  not  to  exceed  the 
proper  limits  of  a  book  designed  for  clinical  and  didactic  use  a  most 
careful  selection  had  to  be  made  from  the  vast  aggregate  of  knowledge 
constituting  the  modern  science  of  Anatomy.  If  in  parts  the  text  may 
appear  quite  as  much  like  an  anatomical  surgery  as  a  surgical  anatomy, 
it  h  because  of  (lie  author's  belief  thai  tins  is  (lie  best  way  to  complete 
the  study  of  anatomy  and  to  begin  the  study  of  surgery. 

The  author  desires  to  acknowledge  bis  indebtedness  to  the  excellent 

words  of  Joessel,  Tillaux,  Merkel,  and  others,  both  for  anatomical 

the  methods  of  their  presentation,  and  for  numerous  illustrations. 

An  original  work  on    mi  b  ;i   subject   can   no  longer  be  written,  nor 

Could    it   have  ;i,  much    v;ilue    as  a    volume   duly    recognizing    the    vast 

fund  of  information  accumulated  by  tireless  investigators.    A  single 

author  can  only  hope  to  contribute  a  fair  proportion  of  original  knowl- 


iv  PREFACE  TO  THE  SECOND  EDITION 

edge  and   to  present  a  chosen  aspect  of  the  science  in  a  clear  and 
practical  manner. 

The  number  of  excellent  works  on  Applied  Anatomy  is  large  enough 
to  render  the  exhaustion  of  an  edition  of  anyone  a  fair  presumption  of 
its  fitness  to  survive.  An  author  can  respond  only  in  one  way,  namely, 
by  striving  to  improve  his  work  in  revising  it.  This  effort  has  been 
faithfully  made  in  the  new  edition,  and  it  may  impartially  be  said  to 
excel  its  predecessor  in  many  particulars.  The  Sections  on  Cerebral 
Localization,  Craniocerebral  Topography,  the  Abdominal  Viscera, 
or  some  of  the  Pelvic  Viscera,  and  on  the  Spinal  Cord  have  been  re- 
written or  largely  amplified.  Every  page  has  been  carefully  revised, 
and  its  subject-matter  elaborated  wherever  it  seemed  desirable.  The 
volume  has  thus  been  enlarged  by  about  eighty  pages,  and  its  illustra- 
tions increased  by  seventy-five  engravings. 

G.  W. 

117  East  Thirty-sixth  Street,  New  York, 

November,  1908. 


CONTENTS. 


CHAPTER    I. 

the  head  and  neck. 

The   Head 17 

The  Scalp 18 

The  Temporal  Region 24 

The  Bony  Cranium 25 

Construction  and  Lesions  of  the  Cranial  Bones 28 

Fractures  of  the  Skull 30 

The  Contents  of  the  Cranium 33 

The  Cerebral  Membranes 33 

Localization  of  Cerebral  Functions 42 

Craniocerebral  Topography 46 

The  Ear 52 

The  Auricle 52 

The  External  Auditory  Meatus 53 

The  Middle  Ear 58 

The  Mastoid  Antrum 60 

The  Eustachian  Tube 63 

The  Face 65 

Region  of  the  Orbit  and  Eye 65 

The  Eyelids 66 

The  Lacrymal  Apparatus 70 

The  Orbit  and  its  Contents 72 

The  Nose  and  Nasal  Fosssb 79 

The  Accessory  Sinuses  of  the  Nose 87 

The  Face 90 

The  Parotid  Region 99 

The  Jaws 103 

The  Temporomandibular  Joint l()7 

The  Lips 109 

The  Tongue  and  Floor  of  the  Mouth 114 

The  Palate 120 

The  Tonsil* 124 

The  Pharynx 126 

129 

The  Sterno-mastoid  Muscle 130 

The  Occipital  and  Subclavian  Trianglea 132 

The  Submaxillary  Triangle 135 

The  Carotid  Trianglea 139 

Hyoid  Bone 144 

TheLarynj 145 


vi  CONTENTS 

The  Neck  (Continued) 

The  Trachea 149 

The  Thyroid  Gland 152 

The  Parathyroid  Glands 155 

The  Deep  Cervical  Fascia 156 

Lymphatics  of  the  Head  and  Neck 159 

Embryology  of  the  Neck 161 


CHAPTER  II. 

the  upper  extremity. 

The  Region  of  the  Shoulder 163 

The  Anterior  Region  of  the  Shoulder 165 

The  Posterior  or  Scapular  Region 172 

The  External  or  Deltoid  Region 174 

The  Shoulder-joint 175 

The  Axilla 185 

The  Region  of  the  Arm 190 

The  Region  of  the  Elbow 194 

The  Elbow  Joint 197 

The  Forearm 204 

The  Region  of  the  Wrist 208 

The  Hand  and  Fingers 215 

CHAPTER  III. 

the  thorax. 

The  Thoracic  Walls 226 

The  Breast 234 

The  Diaphragm 239 

The  Contents  of  the  Thorax 241 

The  Pleura 241 

The  Lungs 245 

The  Trachea  in  the  Thorax 250 

The  Pericardium 251 

The  Heart •_  253 

The  Aorta  ..-..'" 257 

The  Thoracic  Duct 261 

The  Esophagus 262 

CHAPTER  IV. 

THE  abdomen. 

The  Anterior  Abdominal  Wall 269 

Vessels  and  Nerves  of  the  Anterior  Abdominal  Wall     .      .  278 

Operations  and  Incisions 283 

The  Regions  of  the  Abdomen 286 

The  Umbilicus  and  Umbilical  Hernia 287 

The  Inguinal  Region  and  Inguinal  Hernia 290 

The  Inguinofemoral  Region  and  Femoral  Hernia 301 


CONTEXTS 


vn 


The  Posterior  Abdominal  Wall 307 

The  Iliac  Region 307 

The  Lumbar  Region 312 

The  Abdominal  Cavity 317 

The  Peritoneum 317 

The  Abdominal  Viscera 323 

The  Stomach 323 

The  Small  Intestine 334 

The  Large  Intestine 344 

Ileocecal  Region 344 

The  Colon 353 

The  Liver 359 

The  Gall-bladder  and  Ducts        366 

The  Pancreas 373 

The  Spleen 375 

The  Kidneys 379 

The  Ureters 388 

The  Adrenals  390 

Vessels  of  the  Abdomen 391 

Nerve  Supply  of  the  Abdominal  Viscera 392 

CHAPTER  V. 


THE    PELVIS    AND    PERINEUM. 


The  Pelvis 

The  Lining  of  the  Pelvis   . 
The  Viscera  of  the  Pelvis 

The  Rectum     .... 

The  Bladder     .... 

The  Prostate  .... 

The  Seminal  Vesicles 

The  Vas  Deferens 
The  Female  Pelvic  Genital  Organs 

The  Uterus       .... 

The  Ovary       .... 

I  he  FallopianTubes 

The  Broad  Ligaments 

The  Round  Ligaments 

The  Vagina      .... 

J  he  Female  1  Irethra  . 

I  IAI.S    . 

The  I  emale  External  Genital 
'I  he  Male  I  Urethra 

I  he  Penis 

'I  he  Scrol  um 

'I  he  Testi  .     . 

I  I  IK    PZRINEI  \1         .... 

'1  be  i  .I  Region 


394 
404 
407 
407 
417 
425 
429 
430 
431 
431 
438 
442 
444 
445 
447 
450 
451 
451 
452 
461 
465 
I  r,x 
474 
483 


viii  CONTENTS 

CHAPTER'  VI. 

the  lower  extremity. 

The  Hip 485 

The  Gluteal  Region  or  Buttocks 485 

The  Region  of  Scarpa's  Triangle 489 

The  Hip  Joint 494 

The  Thigh 508 

The  Region  of  the  Knee 511 

The  Knee  Joint 517 

The  Leg 525 

The  Ankle 532 

The  Ankle  Joint 535 

The  Foot 539 

CHAPTER  VII. 

the  spine. 

The  Spine 554 

The  Spinal  Cord 563 


APPLIED  SURGICAL  ANATOMY 


CHAPTER    I. 

THE  HEAD  AND  NECK. 
THE  HEAD. 

General  Considerations. — The  head  is  anatomically  the  most  essen- 
tial and  most  complex  part  of  the  body.  It  is  of  great  practical  interest, 
for  even  its  smaller  parts  are  of  importance  to  the  life  and  well-being 
of  man.  In  individuals  of  medium  height  and  weight  the  head  measures 
I  of  the  body  height  in  men  and  j%  in  women,  and  weighs  jT  of  the  body 
weight  in  men  (4  kg.)  and  y1^  in  women  (3.6  kg.).  The  larger  the 
individual  so  much  smaller  is  the  head  as  compared  with  the  total  height 
and  weight. 

When  the  face  looks  directly  forward  the  external  auditory  meatus 
and  infra-orbital  margin  are  in  a  horizontal  plane.  Such  a  position, 
the  one  most  naturally  assumed,  is  maintained  by  the  posterior  neck 
muscles  and  not  by  gravity,  for  the  line  of  the  latter  lies  in  front  of  the 
transverse  occipito-atlantoid  axis  of  motion. 

As  compared  with  the  human  skull,  that  of  the  higher  apes  (chim- 
panzee, orang,  etc.)  shows  marked  differences,  i.  e.,  the  projection  of 
the  muzzle,  the  greater  size  and  forward  position  of  the  face,  the  greater 
size  of  the  intermaxillary  bones,  the  posterior  and  oblique  position  of 
the  foramen  magnum,  etc.  Idiots'  skulls  approximate  those  of  the  lower 
animals  in  many  respects,  /.  c,  large  face,  small  cranium,  etc. 

The  head  shows  a  tendency  to  asymmetry.  One  error  often  com- 
pensates  for  another,  and  one  is  often  astonished  in  the  examination  of 
the  separate  parts  to  find  considerable  deformity  whose  existence  escapes 
a  general  observation.  Individual  differences  in  the  head  are  marked, 
a>  thej  are  elsewhere  in  the  body,  but  we  are  accustomed  to  observe 
them  more  closely  as  they  are  the  essential  marks  of  individuality. 

But  besides  the  individual  differences  there  arc  those  of  sex,  age  and 
race.    Thus,  the  female  skull  looks  immature,  resembling  that  of  a  child, 

and  is  smaller,  lighter,  broader,  and  less  high,  the  Face  and  lower  jaw  are 

smaller,  and  the  vertex  is  flattened.    The  circumference  of  the  skull  at 

birth  is  greater  than   that  of  any  other  part  of  the  body.     The  skull  at 

birth  i   characterized  by  the  large  size  of  the  cranium  and  the  small  size 

of  the  tare  ;md  the  base;    the  absence  of  the  mastoid  process,  the  diploe, 
and  all  ridges;    the  presence  of  the  anterior  fontanelle  and  the  prominence 
2 


IS  THE  HEAD  AND  NECK 

of  the  frontal  and  parietal  eminences..  It  resembles  more  closely  the 
skull  of  the  lower  animals  than  does  the  adult  skull. 

During  the  first  seven  years  the  skull  grows  very  rapidly,  at  first  more 
or  less  equally.  During  the  first  dentition  the  fontanelles  close,  the  face 
broadens  and  enlarges,  the  jaws  lengthen,  and  the  zygomatic  arches 
project.  Later,  the  base  of  the  skull  lengthens  and  the  face  becomes 
deeper  and  somewhat  longer.  By  the  seventh  year  some  parts  have 
attained  their  growth,  i.  e.,  the  foramen  magnum,  the  petrous  portion  of 
the  temporal  bone,  the  width  of  the  body  of  the  sphenoid  and  of  the 
cribriform  plate.  Near  the  approach  of  puberty  a  second  period  of 
active  growth  begins,  the  face  is  elongated  from  the  increased  height 
of  the  nasal  fossae,  alveolar  arches  and  second  teeth,  and  the  expansion 
of  the  air  sinuses.  In  later  years  the  latter  continue  to  expand,  even  up 
to  old  age,  the  crests  and  ridges  develop  and  the  frontal  region  elongates. 
In  old  age  the  skull  atrophies,  becoming  thinner,  lighter,  and  perhaps 
smaller  by  absorption  on  the  surface  and  redeposit  on  the  interior. '  The 
face  becomes  smaller  by  the  loss  of  the  teeth  and  the  absorption  of  the 
alveolar  processes. 

The  racial  differences,  although  marked  in  typical  examples,  shade 
into  each  other.  According  to  one  classification  we  may  distinguish: 
(1)  the  prognathous,  or  long-headed  type,  with  projecting  jaws  and 
teeth,  as  in  the  negro;  (2)  the  pyramidal,  or  broad,  flat-faced  type,  with 
narrow  forehead,  as  in  the  Mongolian  or  Esquimaux;  and  (3)  the  oval 
type  of  the  European,  with  the  length  of  (1),  or  even  more,  and  the 
breadth  of  (2),  but  the  teeth  do  not  project,  as  in  (1),  nor  the  zygomatic 
arches,  as  in  (2),  and  the  forehead  is  full,  laterally,  and  high.  Again, 
skulls  are  classified  as  I.  Dolicocephalic,  or  "long-headed,"  in  which 
the  occipital  lobes  overlap  the  cerebellum,  and  II.  Brachy cephalic,  or 
"short-headed,"  in  which  the  occipital  lobes  do  not  extend  so  far  back- 
ward. Each  division  is  subdivided  into  orthognathous,  in  which  the 
jaws  and  teeth  do  not  project,  and  prognathous,  in  which  they  do. 

Other  peculiar  forms  of  skull  are  on  the  border  line  of  pathological 
deformities,  depending  upon  the  premature  closure  of  a  certain  suture 
which  prevents  the  growth  of  the  skull  at  right  angles  to  that  suture 
and  forces  it  to  grow  in  other  directions,  if  at  all.  By  the  same  process, 
extended  to  several  sutures,  microcephalus  may  result.  The  latter  may 
be  the  result  or  cause  of  idiocy,  in  the  latter  case  justifying  operation 
(craniectomy). 

The  Scalp. 

The  soft  parts  covering  the  vault  of  the  skull  are  arranged  as  in  no 
other  part  of  the  body.  There  are  five  layers :  (1)  the  skin;  (2)  the  sub- 
cutaneous fatty  tissue;  (3)  the  occipitofron talis  muscles  and  aponeurosis; 
(4)  the  subaponeurotic  areolar  tissue;  and  (5)  the  pericranium.  The 
first  three  layers  are  so  intimately  blended  with  one  another,  especially 
over  the  aponeurotic  portion  of  the  occipitofrontalis,  that  they  form 
virtually  a  single  layer,  the  scalp  (Fig.  1). 


THE  HEAD 


19 


1 .  The  Skin. — The  skin  of  the  scalp  is  thicker  than  that  in  most  regions 
of  the  body,  and  is  thicker  behind  than  in  front.  The  hair  is  so  strongly 
attached  to  the  scalp  that  it  has  supported  the  weight  of  the  body  in 
many  instances  since  the  days  of  Absalom,  as,  for  example,  where  it  is 
caught  in  revolving  machinery  belts  and  the  body  is  drawn  after  it. 
The  entire  scalp  has  also  been  torn  off  in  such  accidents.  The  hair 
should  always  be  shaved  around  scalp  wounds,  otherwise  it  is  impossible 
to  make  and  keep  them  clean.  Although  the  roots  of  the  hairs  may 
extend  deeply  into  the  subcutaneous  fatty  tissue,  the  numerous  sebaceous 
(/lands  associated  with  them  are  mostly  superficial  in  the  skin.  These 
may  develop  into  sebaceous  tumors  or  wens,  which  are  more  common 
here  than  in  any  other  part  of  the  body.  Owing  to  their  superficial 
position,  external  to  the  aponeurosis,  they  are  easily  and  safely  removed. 


CEREBRAL    VEIN 


SUBCUTANEOUS 
TISSUE 

5^ — APONEUROSIS 

SUBAPONEUROTIC    TISSUE 
PERICRANIUM 

«1 — SAGITTAL    SUTURE 
PARIETAL    BONE 

TWO    LAYERS    OF    DURA 
LONGITUDINAL    SINUS 


FALX    CEREBRI 


Frontal  section  of  scalp  and-skullithrough  the  sagittal  suture  and  (he  superior  longitudinal  sin 


Care  must  be  taken,  however,  in  removing  suppurating  sebaceous  cysts 
not  to  divide  the  aponeurotic  layer,  on  account  of  the  danger  of  infection 
of  the  loose  tissue  beneath. 

_'.  The  Subcutaneous  Tissue. — The  subcutaneous  tissue,  5  to  ('»  mm. 
<\  in.)  in  thickness,  is  composed  of  a  great  number  of  strong  fibrous 

bands  closely  binding  together  the  skin   and  aponeurosis  and   forming 

a  multitude  of  small  compartments  enclosing  lobules  of  fat.     (  h\  account 

of  thi^  disposition  of  the  fat  it  follows  that  fatty  tumors  arc  rare  and  that 

there  is  but  little  increase  of  it  iii  obesity,  though  a  perceptible  decrease 

after  long  sickness.     The  falling  out  of  die  hair  in  such  cases  may 

be  partly  due  to  this  fact. 
The  arrangement  of  this  subcutaneous  tissue,  like  that  in  the  palm, 

admirably  adapt-  il  to  resist  preS8Ure.     Il  makes  the  density  of  the  scalp 

inch  thai  in  surface  inflammations,  as  in  erysipelas,  the  hairy  scalp 


20  THE  HEAD  AND  NECK 

is  but  little  reddened,  swells  but  slightly,  and  is  extremely  painful. 
Erysipelas  of  the  hairy  scalp  may,  therefore,  be  difficult  to  recognize. 
This  layer  attaches  the  skin  so  closely  to  the  aponeurosis  and  muscle  that 
the  former  moves  with  all  the  movements  of  the  latter.  Furthermore, 
this  layer  contains  the  vessels  which  supply  the  three  layers  of  the  scalp. 
These  vessels  are  closely  connected  with  the  fibrous  partitions  of  this 
layer,  so  that  in  wounds  of  the  scalp  the  vessels  which  are  divided  are 
unable  to  retract  or  contract,  hence  hemorrhage  is  free  and  is  not  spon- 
taneously arrested. 

3.  The  Aponeurosis. — The  aponeurosis  occupies  the  space  between 
the  two  muscular  portions  of  the  occipitofrontalis,  in  front  and  behind. 
Laterally  it  extends  down  over  the  temporal  fascia,  and  becomes  con- 
nected with  it  and,  hence,  with  the  zygomatic  arch. 

4.  The  Subaponeurotic  Areolar  Layer. — The  subaponeurotic  areolar 
layer  is  a  layer  of  loose  connective  tissue  whose  looseness  serves,  like  a 
serous  membrane,  to  facilitate  the  movement  of  the  scalp  upon  the  peri- 
cranium, a  condition  which  is  more  marked  in  the  young  than  in  the  old. 
This  looseness  of  attachment  allows  the  gaping  of  scalp  wounds  and  the 
ready  separation  of  large  flaps  of  scalp  by  injuries,  operations,  scalping 
by  Indians,  or  in  autopsies.  It  is  known  as  the  dangerous  area  of  the  scalp, 
for  its  loose  structure  allows  the  wide  and  rapid  spread  of  inflammation 
and  pus,  posteriorly  as  far  as  the  superior  curved  line,  anteriorly  to  the 
superciliary  ridges,  and  laterally  to  the  level  of  the  zygoma.  Wounds 
or  incisions  which  extend  through  the  entire  scalp  and  open  into  this 
layer  are  much  more  serious  than  more  superficial  ones  on  account  of 
the  more  serious  consequences  of  infection.  This  layer  contains  but  few 
bloodvessels  which  cross  it  to  enter  the  pericranium,  otherwise  large 
effusions  of  blood  would  be  far  more  common  here  than  they  are.  Tumors 
situated  external  to  the  aponeurosis  move  with  the  scalp;  immovable 
growths  are  probably  beneath  the  aponeurosis. 

5.  The  Pericranium. — The  pericranium  is  remarkable  for  its  slight 
adherence  to  the  bone  except  along  the  sutures,  where  it  is  attached  to  the 
suture  membrane  and  is  thus  continuous  with  the  dura,  as  it  is  also  at  the 
foramina.  Hence  inflammation  may  extend  by  continuity  from  the  peri- 
cranium to  the  dura  at  the  foramina  and  sutures  where  the  two  become 
continuous.  In  the  adult  it  is  more  adherent  to  the  bone  than  in  children. 
It  follows  also  that  the  pericranium  may  be  widely  stripped  up  from 
the  underlying  bone  in  extensive  scalp  wounds.  Such  an  injury  is  of 
less  importance  than  we  would  expect  from  analogy  with  similar  injuries 
of  the  periosteum  elsewhere.  The  skull  bones  seldom  necrose  under 
such  circumstances,  for  they  derive  their  main  blood  supply  from  the 
vessels  of  the  diploe  and  dura.  For  a  similar  reason  loss  of  bone  in  the 
vault  of  the  adult  skull  due  to  injury,  necrosis,  or  operation  is,  as  a  rule, 
not  repaired,  for  neither  the  pericranium  nor  the  dura  reproduce  bone 
as  does  the  periosteum. 

Vessels  of  the  Scalp. — The  vascularity  of  the  scalp  is  greater  than 
that  of  any  other  part  of  the  surface.  Flaps  of  scalp,  however  large 
and  extensively  stripped  up,  almost  always  live,  for  the  scalp  carries 


THE  HEAD  21 

its  own  blood  supply,  which  enters  at  the  pedicle  of  the  flap.  Slough- 
ing and  gangrene  from  pressure  are  rare,  owing  to  the  density  of  the 
scalp  tissue  in  which  the  vessels  run.  Unlike  other  regions  of  the  body, 
where  vessels  of  any  size  are  subfacial,  the  vessels  of  the  scalp  lie  in  the 
subcutaneous  tissue  alone. 

The  Arteries. — The  arteries  come  from  the  occipital,  posterior  auricular, 
and  superficial  temporal  branches  of  the  external  carotid  and  from  the 
supra-orbital  and  frontal  branches  of  the  ophthalmic.  Each  vessel  con- 
verges upward  toward  the  vertex  of  the  skull  and  anastomoses  freely  with 
the  adjoining  ones  and  with  its  fellow  of  the  opposite  side.  It  follows 
that  incisions  should  be  planned  as  far  as  possible  to  radiate  from  the 
vertex,  or,  if  horseshoe-shaped,  to  have  the  base  below.  To  prevent 
hemorrhage  during  an  operation,  rubber  tubing  may  be  tightly  drawn 
around  the  base  of  the  scalp,  or,  to  diminish  it,  overlapping,  interrupted, 
temporary  sutures  may  be  applied  between  the  incision  or  flap  and  the 
base  of  the  scalp,  from  whence  the  arteries  pass  upward.  The  frontal 
artery,  emerging  at  the  inner  angle  of  the  orbit  on  each  side,  enters 
at  the  base  of  and  nourishes  a  frontal  rhinoplastic  flap.  The  tem- 
poral artery,  with  its  vein  and  the  auriculotemporal  nerve  behind  it, 
ascends  between  the  condyle  of  the  jaw  and  the  external  auditory  meatus 
over  the  posterior  root  of  the  zygoma  and  divides  into  its  anterior  and 
posterior  branches  3.7  to  5  cm.  (l|to2  in.)  above  the  latter.  Its  pulsation 
is  a  convenient  guide  to  the  anesthetist.  It  presents  in  a  high  degree  the 
tortuosities  of  the  arteries  of  the  head,  especially  its  anterior  branch,  and 
in  the  aged  it  affords  early  evidence  of  arterial  sclerosis.  It  is  the  most 
frequent  situation  for  cirsoid  aneurysm,  and  is  more  frequently  wounded 
than  almost  any  other  artery  of  the  body.  The  posterior  auricular  artery 
and  nerve  run  in  the  angle  between  the  ear  and  the  mastoid  process. 
The  occipital  artery  ascends  a  finger's  breadth  behind  the  mastoid  process 
and  reaches  the  scalp,  with  the  great  occipital  nerve,  a  little  posterior  to 
a  point  midway  between  the  mastoid  process  and  the  occipital  protuber- 
ance. These  arteries  all  share  the  peculiarity  of  being  subcutaneous 
instead  of  being  subaponeurotic. 

The  Emissary  Veins. — The  emissary  veins  connect  the  dura!  sinuses, 
and  indirectly  the  veins  of  the  pia-araelmoid,  with  the  superficial 
reins  at  certain  points  through  apertures  in  the  skull,  and  hence  are  of 
considerable  practical  importance.  They  afford  a  channel  for  the  spread 
of  inflammation  from  the  surface,  to  (lie  sinuses  or  meninges,  thereby 
causing  sinus  thrombosis  or  meningitis,  as  in  eases  of  erysipelas  and 
suppuration  of  the  scalp  or  necrosis  of  the  cranial  bones.  Their  presence 
adds  greatly  to  the  seriousness  of  injuries  and  diseases  of  the  scalp. 
Tliev  also  assist  in  equalizing  the  intracranial  pressure,  and  for  this  pur- 
developed  in  early  life,  during  the  period  of  brain  growth. 

r><  ides  very  numerous  small  veins,  the  most  constant  and  important 
of  the  larger  emissary  veins  connecting  with  the  veins  of  the  scalp  are: 
(1)  the  vein  passing  through  (lie  mastoid  foramen  which  connects  the 
lateral  sinus  with  the  occipital  (or  posterior  auricular)  vein;  (2)  the 
vein  pa  ring  through  the  posterior  condylar  foramen  which  connects 


22  THE  HEAD  AND  NECK 

the  sigmoid  sinus  with  the  deep  veins  at  the  back  of  the  neck;  (3)  the 
vein  passing  through  the  parietal  foramen  which  connects  the  superior 
longitudinal  sinus  with  the  veins  of  the  scalp.  The  mastoid  emissary 
vein  accdunts  for  the  practice  of  bloodletting  or  blistering  behind  the  ear 
in  some  cerebral  affections  and  for  the  edema  behind  the  mastoid  process 
in  lateral  sinus  thrombosis.  For  the  other  emissary  veins  see  any  descrip- 
tive anatomy. 

The  veins  of  the  scalp  are  also  connected  by  many  minute  veins 
with  the  veins  of  the  diploe.  The  latter  are  not  well  developed  until 
after  the  tenth  year,  when  the  diploe'  develops  and  they  are  separate  for 
each  bone  until  the  ossification  of  the  sutures  (Testut).  The  veins  of 
the  diploe  communicate,  the  anterior  two  (frontal  and  anterior  temporal) 
with  the  surface  veins  (supra-orbital  and  deep  temporal),  the  posterior 
two  (posterior  temporal  and  occipital)  with  the  lateral  sinus.  The  anas- 
tomosis between  the  supra-orbital  and  other  facial  tributaries  at  the 
inner  angle  of  the  orbit  with  the  ophthalmic  vein  affords  a  free  commu- 
nication between  the  extra-  and  intracranial  circulation,  as  the  ophthal- 
mic is  a  tributary  of  the  cavernous  sinus.  Thus,  we  see  the  number 
of  channels,  and  there  are  other  less  conspicuous  ones,  through 
which  inflammation  can  spread  from  the  surface  to  the  interior  of  the 
skull.  x 

The  Lymphatics. — The  lymphatics  of  the  scalp  may  be  divided  into 
three  groups:  (1)  the  occipital  emptying  into  the  suboccipital  nodes; 
(2)  the  posterior  parietal  emptying  into  the  mastoid  nodes;  and  (3)  the 
anterior  parietal  and  frontal  which  empty  into  the  parotid  nodes.  Some 
vessels  from  the  frontal  region  end  in  the  submaxillary  nodes.  A  knowl- 
edge of  these  regions  and  their  nodes  is  of  service  in  the  diagnosis  of  scalp 
troubles  in  which  they  are  affected. 

With  regard  to  the  nerves  which  supply  the  scalp  it  is  only  necessary 
to  say  that  those  which  are  branches  of  the  fifth  nerve  are  not  infrequently 
the  seat  of  neuralgia,  especially  the  supra-orbital  nerve,  less  often  the 
auriculotemporal.  The  former  emerges  from  the  orbit  at  the  supra- 
orbital foramen  or  notch,  at  the  junction  of  the  inner  and  middle  thirds 
of  the  supra-orbital  margin.  Here  it  may  be  readily  found  and  divided 
or  resected  in  some  forms  of  obstinate  frontal  headache  due  to  neuralgia 
of  this  nerve.  The  inner  branch  reaches  back  to  the  middle  of  the 
parietal  bone,  the  outer  branch  as  far  as  the  lambdoid  suture.  As  the 
fifth  nerve  supplies  the  dura  as  well  as  the  greater  part  of  the  scalp, 
pain  due  to  a  lesion  of  the  former  may  be  referred  to  a  similar  point  of 
the  latter  so  as  to  be  of  use  in  localization. 

Wounds. — Wounds  of  the  scalp  do  not  gape  unless  the  aponeurosis  or 
muscle  is  divided.  Those  wounds  gape  most  which  are  transverse  to  the 
muscle  fibers,  next  those  transverse  to  the  aponeurotic  fibers,  and  those 
gape  least  which  are  parallel  with  them,  i.  e.,  anteroposterior.  As  the 
scalp  is  firmly  stretched  over  the  hard  bone  beneath,  contused  wounds 
often  appear  as  cleanly  cut  as  incised  wounds.  Wounds  resembling 
incised  wounds  may  also  be  produced  from  within  by  the  sharp  edge  of 
the  superciliary  ridge  when  struck  by  a  blunt  object. 


THE  HEAD  23 

Bleeding. — Bleeding  from  scalp  wounds  is  very  free,  and  unless 
properly  treated  very  prolonged.  There  is  little  or  no  tendency  to  the 
spontaneous  arrest  of  hemorrhage,  for  the  arteries,  owing  to  their  adhesion 
to  the  tissues  of  the  scalp,  are  unable  to  retract  or  contract  when  divided, 
and  it  is  by  this  process  that  bleeding  is  ordinarily  spontaneously  arrested. 
This  adhesion  of  the  vessels  to  the  fibrous  partitions  and  the  density  of 
the  scalp  account  for  the  difficulty  of  tying  a  bleeding  artery  in  the  scalp, 
hence  to  arrest  hemorrhage  we  often  depend  upon  pressure,  transfixion, 
or  upon  suturing  the  edges  of  the  wound  firmly  together.  Fortunately, 
as  we  have  seen  above,  there  is  very  little  danger  of  sloughing  on  account 
of  pressure.  In  addition  to  the  arrest  of  bleeding,  we  have  to  think  of 
the  possibilities  of  inflammation  in  scalp  wounds. 

Inflammation  or  Abscess. — Inflammation  or  abscess  in  the  scalp 
may  occur  in  one  of  three  situations:  (1)  in  the  subcutaneous  tissue;  (2) 
between  the  aponeurosis  and  the  pericranium;  and  (3)  beneath  the  peri- 
cranium. Abscesses  of  the  first  variety  are  small  and  spread  only  with 
the  greatest  difficulty  in  the  dense  tissue.  In  the  second  situation  inflam- 
mation or  abscess  may  be  very  serious  on  account  of  its  easy  spread  in 
the  loose  tissue  and  the  danger  of  the  infection  extending  within  the 
cranium.  Inflammations  of  this  kind  may  follow  scalp  wounds  dividing 
the  aponeurosis,  and  the  chief  danger  of  these  wounds  lies  in  such  inflam- 
mations. The  inflammation  may  undermine  the  entire  scalp,  and  is 
limited  only  by  the  attachments  of  the  aponeurosis  as  given  above. 
Abscesses  extending  to  the  limits  of  this  area  should  be  opened  and 
drained  above  the  line  of  attachment  of  the  aponeurosis.  The  scalp 
does  not  perish  even  in  the  most  extensive  cases,  as  it  carries  its  own 
blood  supply;  but  the  wounds  which  lead  to  the  abscess  or  are  made  to 
relieve  it  are  often  slow  to  heal,  as  the  abscess  walls  fail  to  obtain  perfect 
rest,  owing  to  the  movements  of  the  occipitofrontalis  muscle.  Abscess 
beneath  the  pericranium  is  limited  to  the  surface  of  one  bone,  as  this 
membrane  is  adherent  to  the  suture  membrane.  It  is  most  often  the 
result  of  necrosis  of  the  cranial  bones. 

Hematomas. — Hemotomas  of  the  scalp  may  be  classified  in  the  same 
manner  as  abscess.  They  occur  most  frequently  outside  of  the  aponeuro- 
sis in  the  subcutaneous  (issue  which  contains  the  greater  part  of  the  blood- 
els.  In  this  situation  the  extravasation  of  blood  is  usually  small  and 
sharply  limited  by  the  density  of  the  tissues,  and  is  confined  to  the  area 
where  the  tissues  are  lacerated  by  the  violence.  Such  extravasations  of 
blood  produce  a  tumor  on  the  surface  whose  thin  edges  become  hard 
from  the  coagulation  of  the  thin  layer  of  blood,  while  the  thicker  centre 
remains  soft  for  a  time.  A  (inn,  sharp  margin  often  separates  these 
two  parts,  which  may  lead  to  an  error  in  diagnosis  by  mistaking  it  for 
the  margin  of  a  fracture  of  the  skull  and  the  soft  centre  for  the  depression 
of  ;m  area  of  the  skull.  This  error  may  be  avoided  by  observing  the 
projection  of  the  blood  tumor  OB  the  surface  and  by  moving  the  scalp 
back  and  forth,  when  the  supposed  depressed  area  moves  with  the  scalp 

r  the  surface  of  the  skull.    Again,  the  sharp  margin  of  the  hematoma 

will  pit  on  firm  pressure,  SO  that   the  bone  is  felt   beneath.     Owing  to  its 


24  THE  HEAD  AND  NECK 

proverty  in  bloodvessels,  the  loose  tissue  beneath  the  aponeurosis  is  not 
often  the  seat  of  a  hematoma  except  as  the  result  of  fracture  of  the  skull, 
or  when  the  aponeurosis  is  torn  by  the  injury.  When  they  occur  here 
they  may  attain  a  large  size  and  may  similarly  present  hard  edges  and  a 
soft  centre,  simulating  depressed  fracture,  from  which  they  cannot  be 
so  readily  distinguished  by  moving  the  scalp. 

Extravasations  of  blood  beneath  the  pericranium  are  limited  in  area  to 
one  bone,  and  may  be  diagnosticated  by  this  fact.  They  are  commonly 
called  cephalhematomata,  are  usually  congenital  in  orgin,  due  to  pressure 
on  the  head  at  birth,  and  hence  are  more  frequent  in  males  owing  to  the 
larger  size  of  the  head.  They  are  most  common  over  the  parietal  bone 
and  on  the  right  side,  which  is  most  exposed  to  pressure.  Besides  these 
blood  tumors  beneath  the  pericranium  others  occur  rarely  which  have  a 
different  origin  and  are  distinguished  by  disappearing  on  pressure,  in 
whole  or  in  part,  or  even  in  the  upright  posture.  Such  tumors  according 
to  their  position  are  connected  either  with  the  veins  of  the  diploe  or  the 
dural  sinuses  through  an  opening  which  may  be  the  result  of  injury, 
disease,  or  congenital  defect.  When  communicating  with  the  superior 
longitudinal  sinus  they  are  median  and  receive  a  faint  pulsation  from  the 
brain. 

The  Temporal  Region. 

The  temporal  region  varies  in  some  respects  from  the  scalp  proper 
as  to  the  soft  parts  covering  it.  The  limits  of  this  region  may  be  taken 
to  be  the  upper  border  of  the  zygomatic  arch,  the  external  auditory 
meatus,  and  the  base  of  the  mastoid  process  below  and  the  curved  superior 
temporal  ridge  above.  The  latter  ridge  connects  the  base  of  the  mastoid 
bone  with  the  external  angular  process  of  the  frontal  bone  and  rises 
7  to  8  cm.  (about  3  in.)  above  the  level  of  the  zygomatic  arch.  This 
region  corresponds  to  the  temporal  fossa,  and  its  upper  limits  may  be 
determined  by  making  the  temporal  muscle  to  contract.  The  various 
layers  of  soft  parts  common  to  this  region  and  the  occipitofrontal  are 
identical  above,  where  they  really  form  a  part  of  the  scalp,  but  change 
in  character  below.  Thus  the  skin  below  is  less  dense,  less  thick,  and 
less  adherent  to  the  subcutaneous  tissue  and  is  wanting  in  hair  below 
and  in  front.  The  subcutaneous  tissue  below  becomes  loose  and 
resembles  that  elsewhere  in  the  body,  and  the  arteries  are  no  longer 
intimately  adherent  to  its  septa.  The  aponeurosis  passes  down  over 
and  becomes  attached  to  and  continuous  with  the  temporal  fascia. 

The  Temporal  Fascia. — The  temporal  fascia,  whose  form  represents 
exactly  that  of  this  region,  is  very  dense,  and  unyielding,  so  that  in  the 
case  of  an  injury  reported  by  Denonvilliers  a  lacerated  wound  of  this 
fascia  was  at  first  mistaken  for  a  fracture  of  the  skull.  In  its  lower 
fourth  it  is  double,  enclosing  fat  and  the  orbital  branch  of  the  temporal 
artery  between  its  two  layers,  which  are  attached  to  the  outer  and  inner 
aspects  of  the  upper  border  of  the  zygomatic  arch.  Between  it  and  the 
bone  is  an  osseo-aponeurotic  space  which  is  deepest  in  front,  2.5  cm. 


THE  HEAD  25 

(1  in.),  and  narrows  behind  and  above  until  we  reach  the  attachment  of 
the  fascia  to  the  bone.  This  space  lodges  the  temporal  muscle  and  deep 
temporal  vessels  and  nerves.  It  is  hermetically  closed  above  by  the 
attachment  of  the  fascia  to  the  temporal  ridge,  while  below  it  is  directly 
continuous  with  the  zygomatic  fossa,  so  that  surgically  the  two  fossa? 
form  but  a  single  region.  Hence  abscess,  etc.,  in  the  temporal  fossa  is 
prevented  by  the  firm  fascia  from  opening  above  the  zygoma  and  tends  to 
extend  downward  into  the  zygomatic  fossa  and  the  neck.  Owing  to  the 
density  of  the  fascia,  pathological  collections  beneath  it  do  not  show  on 
the  surface. 

As  in  the  scalp,  inflammatory  products  or  blood  may  collect  in  the 
subcutaneous  or  subaponeurotic  layers,  in  which  situations  they  may 
be  wholly  above  the  zygoma  or  sink  in  part  below  its  level.  Subcutaneous 
effusions  lie  external  to  the  zygomatic  arch,  while  those  beneath  the 
fascia  are  internal  to  the  arch.  In  the  temporal  region  the  pericranium 
is  much  thinner  and  more  adherent  to  the  bone,  while  the  dura  is  less  so 
than  it  is  above;  hence  subpericranial  extravasations  are  rare,  while 
epidural  extravasations  are  more  common  than  elsewhere. 

As  the  muscle  is  separated  from  the  fascia  in  the  lower  third  of  this 
region  by  a  mass  of  fat,  continuous  with  the  abundant  masses  in  the 
zygomatic  fossa,  we  see  that  there  are  three  distinct  layers  of  fat  between 
the  surface  and  the  muscle:  (1)  subcutaneous;  (2)  interfascial;  and  (3) 
subfascial.  This  fat  diminishes  in  wasting  diseases,  giving  a  sunken 
appearance  to  the  temporal  region,  and  bringing  the  zygomatic  arch  and 
the  malar  bone,  below  and  in  front,  into  prominent  relief. 


The  Bony  Cranium. 

Surface  Landmarks. — Those  that  can  be  determined  through  the 
overlying  scalp  are  of  the  most  surgical  importance  in  relation  to  cranio- 
cerebral topography.  The  external  occipital  protuberance,  or  inion,  is 
readily  felt  in  the  median  line.  It  is  the  thickest  part  of  the  vault,  and 
corresponds  about  to  the  torcular  Herophili  on  the  inner  surface.  The 
glabella,  the  median  smooth  area  between  the  superciliary  ridges  of  the 
frontal  bone,  can  be  felt  just  above  the  notch  (naswn)  at  the  nasofrontal 
BUture.  The  external  angular  process  of  the  frontal  bone  at  the  outer  end 
of  the  supra-orbital  ridge  is  readily  felt.  Measurements  are  taken  from 
it-  upper  and  outer  part.  It  should  not  be  confounded  with  a  projection 
on  the  back  of  the  frontal  process  of  the  malar  bone  below  it.  The  zygo- 
matic arch,  the  external  auditory  meatus,  and  the  mastoid  process c&n  nil 
be  readily  seen  or  felt.  The  upper  branch  of  the  posterior  root  of  the 
zygoma  [supramastoid  crest)  miming  into  the  posterior  pari  of  the  tem- 
poral ridge  can  be  felt  above  and  behind  the  external  auditory  meatus. 
The  parietal  eminence  i-  used  as  a  landmark,  but  is  not  n  well-marked  one. 
To  determine  it  the  scalp  should  be  shaved,  and  it  can  be  more  accurately 
determined  when  the  skull  i-  bared.     It  i-  more  prominent  in  young 

-hull   . 


26  THE  HEAD  AND  NECK 

In  addition  to  these  palpable  or  visible  landmarks  and  by  means  of 
them  we  can  determine  the  position  of  the  sutures.  The  bregma,  the 
site  of  the  anterior  fontanelle  where  the  sagittal  and  coronal  sutures 
meet,  lies  at  the  intersection  of  the  median  line  with  a  vertical  line  drawn 
from  a  point  just  in  front  of  the  external  auditory  meatus.  The  coronal 
suture  lies  in  a  line  from  the  bregma  to  the  middle  of  the  zygomatic  arch. 
The  pterion,  where  the  frontal,  parietal,  and  great  wing  of  the  sphenoid 
meet,  lies  on  this  line  3  to  3.7  cm.  (1^  to  1^  in.)  behind  the  external  angular 
process  of  the  frontal  and  about  the  same  distance  above  the  zygoma. 
The  sagittal  suture  is  median  and  extends  between  the  bregma  and  the 
lambda.  The  latter  corresponds  to  the  posterior  fontanelle  and  is  about 
midway  between  the  bregma  and  inion  (external  occipital  protuberance), 
or  7  cm.  (2|  in.)  above  the  latter.  The  parietal  foramen  is  about  4  cm. 
(If  in.)  above  the  lambda.  The  lambdoid  suture  joins  the  sagittal  at  the 
lambda  and  extends  thence  along  a  line  drawn  to  the  posterior  end  of  the 
base  of  the  mastoid  process,  or  it  may  be  represented  by  the  posterior 
two-thirds  of  a  line  from  the  lambda  to  the  apex  of  the  mastoid.  The 
asterion,  at  the  postero-inferior  angle  of  the  parietal  bone  where  the 
lambdoid  and  parietomastoid  sutures  meet,  lies  on  the  last-mentioned 
line  4.5  cm.  (If  in.)  behind  the  meatus  and  on  a  level  with  the  zygoma. 
The  summit  of  the  squamous  suture  is  about  5  cm.  (2  in.)  above  the 
zygomatic  arch.  It  should  be  remembered  that  the  frontal  suture, 
between  the  two  halves  of  the  frontal  bone,  sometimes  persists,  and  should 
not  be  mistaken  for  a  fracture. 

The  sutures,  besides  interlocking  in  a  serrated  or  dentated  manner, 
are  bevelled  alternately  at  the  expense  of  the  outer  and  inner  aspect. 
Thus,  in  the  coronal  suture  the  frontal  overlaps  the  parietal  above  and 
is  overlapped  by  it  below.  In  injuries  to  the  skull  diastasis  or  separation 
of  the  bones  at  the  sutures  occurs  in  but  a  very  small  percentage  of 
cases,  and  then  usually  in  connection  with  an  extensive  fracture.  It  is 
naturally  more  common  in  young  than  in  adult  skulls.  The  squamous 
suture  is  the  one  where  diastasis  is  most  common,  or  when  associated 
with  fracture,  the  sagittal  and  coronal  sutures.  The  suture  membranes 
in  young  skulls  are  thick  and  vascular,  so  that  a  surface  inflammation  may 
travel  through  them  to  the  internal  surface  of  the  cranium,  and  vice  versa. 
In  infants  at  birth  they  are  so  broad  as  to  allow  the  bones  to  slide  upon 
one  another  and  thus  provide  for  the  moulding  of  the  head  in  its  passage 
through  the  pelvis.  In  hydrocephalus  the  sutures,  especially  those  around 
the  parietal  bone,  become  widely  separated  and  the  fontanelles  form 
large  openings  whose  closure  is  much  delayed.  The  posterior  fontanelle 
is  normally  closed  at  birth,  or  a  month  or  two  later,  the  anterior  during  the 
second  year,  up  to  which  time  it  acts  as  a  safety  valve  for  the  rapidly 
varying  intracranial  pressure.  It  may  persist  much  longer,  even  to 
adult  life.  The  fontanelles  aid  in  determining  the  position  of  the  infant's 
head  during  parturition. 

As  the  sutures  with  their  membranes  allow  the  rapid  growth  of  the 
skull,  their  premature  closure  prevents  the  growth  of  bone  in  a  line  at 
right  angles  to  them.    This  causes  a  deformity  in  shape  of  the  skull  or, 


THE  HEAD  27 

if  more  general,  a  small  size  (microccphalus)  of  the  skull,  which  may  be 
the  cause  or,  more  often,  the  result  of  arrested  brain  development  or 
idiocy.  If  it  be  the  cause  of  idiocy,  microccphalus  calls  for  craniectomy 
to  allow  for  the  growth  of  the  brain.  Such  premature  ossification  may 
be  due  to  rickets. 

The  sutures  assist  slightly  to  break  the  force  of  shocks  and  diminish 
the  liability  of  fracture,  hence  the  latter  would  seem  more  likely  to  follow 
a  slight  injury  after  the  closure  of  the  sutures,  which  occurs  at  varying 
periods  after  middle  life.  This  closure  begins,  as  in  the  long  bones,  at 
the  end  of  the  suture  last  ossified,  i.  e.,  near  the  fontanelles,  and  occurs 
first  in  the  sagittal,  last  in  the  squamous  suture.  It  is  said  to  begin  when 
the  weight  of  the  brain  ceases  to  increase,  and  may  be  complete  by  the 
age  of  eighty  (Tillaux). 

The  Wormian  bones  occur  in  varying  numbers  and  sizes  along  the 
sutures,  most  often  in  the  lambdoid  suture,  and  may  be  mistaken  for 
fragments  due  to  fracture.  One  of  these  bones,  the  epipteric  bone,  is 
found  at  the  pterion  and  usually  joins  the  great  wing  of  the  sphenoid, 
of  which  it  may  be  thought  to  be  a  broken  fragment.  It  may  be  met 
with  in  trephining  for  the  middle  meningeal  artery. 

In  craniotabes  ascribed  to  rickets  or  inherited  syphilis,  the  softened 
skull  is  deformed  and  flattened  in  the  occipital  and  posterior  parietal 
regions  by  the  pressure  of  the  head  resting  largely  on  this  part.  In  these 
same  areas  the  bone  may  become  very  much  thinned  or  even  wanting 
by  the  combined  pressure  from  within  and  without. 

Conditions  Depending  upon  Errors  of  Development. — The  frontal, 
parietal,  and  squamous  portion  of  the  temporal  and  the  part  of  the  occipital 
above  its  highest  curved  line  are  formed  in  membrane,  the  base  of  the 
skull  in  cartilage.  The  entire  absence  of  that  part  formed  in  membrane 
is  occasionally  found  as  an  anomaly.  The  squamous  portion  of  the  occip- 
ital bone  is  ossified  from  four  centres,  a  pair  above  the  highest  curved 
line  and  a  pair  below.  The  upper  pair  may  form  a  separate  bone,  the 
interparietal  bone  of  the  lower  vertebrates,  and  the  suture  between  this 
and  the  part  below  should  not  be  mistaken  for  a  fracture.  More  com- 
monly there  persist  two  lateral  fissures,  as  at  birth,  or  median  fissures 
between  the  lateral  centres,  and  these  fissures  also  should  not  be  mis- 
taken for  fractures. 

Certain  tumors  of  congenital  origin,  containing  cerebral  contents  and 
calico1  cephaloceles  or  "cerebral  hernia\"  occur  as  the  result  of  such 
defective  development.  They  are  usually  situated  in  the  median  line 
mid  most  often  in  the  occipital,  next  in  frequency  in  the  nasofrontal 
region.  Occipital  cephaloceles  generally  occur  through  a  median  fissure 
in  the  occipital  bone,  either  above  or  below  the  external  occipital  pro- 
tuberance; anterior  or  .sincipital  cephaloceles  through  the  nasofrontal 
SUture.  More  rarely  such  tumors  occur  through  other  abnormal  aper- 
ture^, especially  at  the  base  of  the  skull.  When  the  sac  of  a  cephalo- 
cele,  which  is  formed  by  the  outer  eranial  membranes,  contains  cerebro- 
spinal fluid  alone  the  tumor  is  called  a  meningocele;  when  it  contains 
brain  sub  tanee,  an  encephalocele.     A  hydrencephalocele  is  an  encephalo- 


28  THE  HEAD  AND  NECK 

cele  containing  a  cavity  filled  with  fluid  which  is  often  connected  with  the 
cerebral  ventricles. 

The  parietal  fissure  is  a  narrow  gap-  extending  from  the  parietal 
eminence  to  the  sagittal  suture  about  2.5  cm.  (1  in.)  in  front  of  the  lambda. 
It  is  often  seen  about  the  fifth  month  of  fetal  life  as  a  cleft  between  the 
radiating  ossific  spicules,  but  it  usually  closes.  When  present  on  both 
sides  the  lozenge-shaped  gap  is  known  as  the  sagittal  fontanelle.  The 
fissure  should  not  be  mistaken  for  a  fracture. 

Construction  and  Lesions  of  the  Bones  of  the  Cranial  Vault. — In  the 
adult  these  bones  are  composed  of  compact  outer  and  inner  tables  and  an 
intervening  cancellous-like  layer,  the  diploe.  This  is  not  present  in  the 
thinnest  part  of  the  skull  or  in  children's  skulls,  and  does  not  form  until 
about  the  tenth  year.  The  blood  supply  of  these  bones  is  contained  largely 
in  the  diploe,  which  receives  but  little  blood  from  the  vessels  of  the  peri- 
cranium, more  from  those  of  the  dura.  Some  of  the  consequences  of  this 
we  have  already  seen  (pp.  20,  22).  The  veins  of  the  diploe  empty  into 
both  the  dural  sinuses  and  the  surface  veins.  As  the  vessels  of  the  diploe 
communicate  with  those  of  the  dura  and  the  dural  sinuses,  inflammatory 
lesions  of  the  bone  may  extend  to  the  sinuses  and  lead  to  sinus  thrombosis, 
with  the  danger  of  pyemia,  or  to  the  dura  and  cause  pachymeningitis. 

Inflammatory  Lesions. — Inflammatory  lesions  of  the  bones  commonly 
lead  to  caries  or  necrosis,  which  is  not  uncommon  on  the  vault  of  the  skull, 
and  most  often  involves  the  frontal  and  parietal  bones.  Owing  to  its 
poorer  blood  supply  and  its  exposure  to  injuries  the  external  table  is  more 
often  involved  alone  than  the  internal  table.  Syphilis  and  tuberculosis 
are  the  most  common  causes  of  caries  or  necrosis  of  these  bones.  Many 
cases  result  from  injury,  especially  when  the  wound  is  infected,  and  but 
few  cases  are  spontaneous  or  idiopathic.  Besides  the  special  dangers, 
mentioned  above,  of  sinus  thrombosis  and  meningitis,  pus  and  granula- 
tion tissue  may  collect  between  the  bone  and  dura  and  cause  pressure  on 
the  brain  and  cranial  nerves,  but  fortunately  such  a  collection  of  pus  here 
is  not  common.  When  the  disease  of  bone  involves  the  whole  thickness 
of  the  skull  the  pulsations  of  the  brain  may  be  seen  or  felt  in  the  gap 
produced.  Necrosis  with  separation  of  extensive  areas,  even  of  the 
entire  vault,  has  been  reported  (Saviard).  A  peculiarity  of  necrosis 
of  the  cranial  vault  is  that  no  involucrum  is  formed  and  the  bone  is 
not  reproduced.  As  a  rule,  stripping  up  of  the  dura  is  not  followed  by 
necrosis. 

The  average  thickness  of  the  bones  of  the  cranial  vault  is  5  mm.  (^  in.), 
but  this  is  liable  to  wide  variation  in  different  parts  of  the  same  skull  and 
in  different  skulls.  Thus  it  is  very  thin  and  translucent  in  the  squamous 
portion  of  the  temporal,  the  anterior  inferior  angle  of  the  parietal,  and  in 
the  inferior  or  cerebellar  fossae  of  the  occipital  squamosal;  while  it  is 
very  thick  at  the  occipital  protuberance,  the  mastoid  process,  the  lower 
part  of  the  frontal  bone,  and  along  the  ridges  that  bound  the  grooves  for 
the  superior  longitudinal,  the  lateral  and  occipital  sinuses.  It  is  alter- 
nately thick  and  thin  at  the  base.  Again,  the  inner  surface  of  the  cranium 
is  marked  by  depressions  or  grooves:    (1)  for  the  cerebral  convolutions; 


THE   HEAD 


29 


(2)  for  the  dural  sinuses;  (3)  for  the  meningeal  arteries  (especially  the 
middle  meningeal ) ;  and  1 4)  for  the  Pacchionian  bodies.  Hence  the  inner 
and  outer  tables  of  the  skull  are  not  parallel  with  one  another. 

These  facts  should  be  borne  in  mind  in  trephining.  The  pin  of  the 
trephine  should  not  be  made  to  penetrate  over  3  mm.  (\  in.),  and  in  many 
regions  1.5  mm.  [j,.  in).  The  trephine,  burr,  or  drill  should  not  be  applied 
over  the  course  of  the  sinuses,  over  the  position  of  the  frontal  sinuses 
often  of  large  size  in  the  aged),  nor  over  the  position  of  the  middle 
meningeal  artery,  unless  it  is  desired  to  expose  these  parts.  As  the  suture 
membrane  blends  with  the  dura,  these  instruments  should  not  be  applied 
over  the  sutures  for  fear  of  wounding  the  dura.     From  time  to  time 


Fig.  2 


Preparation  of  skull,  showing  tin-  principal  arches  of  strength  or  buttresses  of  resistance. 
(Thompson,  /.  c,  after  Dolbeau  and  Feilizet.) 


the  groove  made  by  the  trephine  should  be  tested  in  its  entire  circum- 
ference by  a  probe  to  see  if  it  is  through  where  the  bone  is  thinnest. 
The  bleeding  in  ;t  trephine  wound  comes  almost  exclusively  from  the 
diplo< 

The  skull  presents  certain  stronger  ridges  or  buttresses  where  the 
bones  are  thicker  or  stronger  and  between  which  they  are  thinner  and 
more  readily  fractured.  These  buttresses  pass  from  the  vault  to  the 
:i  the  foramen  magnum  and  serve  to  unite  the  two  parts  Into  one 
solid  framework.  Tims  one  buttress  is  represented  by  the  median  pari 
of  th<-  frontal,  the  ethmoid,  the  body  of  the  sphenoid,  and  the  basilar 
portion  of  the  occipital.  This  anterior  buttress  is  continuous  along  the 
middle  line  of  the  vertex  with  the  posterior  buttress,  which  passes  through 


30  THE  HEAD  AND  NECK 

the  occipital  protuberance  and  crest  to  the  foramen  magnum.  Two 
lateral  buttresses  exist:  the  anterior,  represented  by  a  ridge  of  bone  from 
the  vertex  to  the  exterior  angular  process  of  the  frontal  and  thence 
through  the  great  wing  to  the  body  of  the  sphenoid,  and  the  posterior, 
running  through  the  parietal  eminence,  mastoid  process,  posterior  part 
of  the  petrous  bone,  and  the  jugular  process  to  the  occipital  condyle.1 

The  bones  of  the  skull  and  the  skull  as  a  whole  are  elastic.  This 
elasticity  is  greater  in  the  infant  than  in  the  aged,  but  even  the  adult 
skull  is  less  brittle  than  commonly  supposed.  The  yielding  character 
of  the  infant's  skull  is  shown  in  the  artificial  deformity  of  the  flat-headed 
Indian,  produced  by  pressure,  and  it  has  been  asserted  (Gueniot)  that 
in  infants  considerable  deformity  may  be  produced  by  the  weight  of  the 
brain,  by  allowing  them  to  lie  always  upon  one  side.  In  addition  in 
the  infant  there  is  much  cartilage  and  membrane  between  the  bones. 
Hence  the  skull  of  an  infant  is  not  easily  fractured.  The  probable  effect 
of  a  blow  is  to  indent  the  skull.  During  delivery  the  infant's  skull,  most 
often  the  parietal  bone  (right  parietal  in  L.  O.  A.  presentations),  may 
be  flattened  by  pressure  against  the  sacral  promontory  or  by  the  use  of 
the  forceps.  Though  a  hemorrhage  (cephalhematoma)  often  occurs 
beneath  the  indented  area,  between  the  bone  and  pericranium,  real 
fracture  is  rare. 

Fractures  of  the  Skull. — That  the  liability  of  the  skull  to  fracture  is 
not  much  greater  is  due  to  the  following  anatomical  conditions:  its 
elasticity,  its  rounded  form  favoring  glancing  blows,  the  density  and 
mobility  of  the  scalp,  the  make-up  of  the  skull  by  a  number  of  bones, 
composed  of  two  plates  or  tables  with  intervening  spongy  bone,  separated 
by  sutures  and  suture  membranes,  which  act  to  a  slight  extent  as  buffers, 
and  the  mobility  of  the  head  on  the  spine. 

Fractures  of  the  skull  vary  from  a  mere  crack  or  fissure  to  an  extensive 
crushing  in,  with  depression.  They  may  be  simple  or  compound. 
Although,  as  a  rule,  the  entire  thickness  of  the  bone  is  involved  in  frac- 
tures of  the  skull,  yet  the  external  table  alone  may  be  broken  or  even 
depressed  into  the  diploe'  or  into  the  frontal  sinuses.  More  rarely  the 
internal  table  may  be  fractured  without  injury  of  the  outer  table.  This 
injury  can  be  explained  and  illustrated  as  follows:  An  injury  causing 
fracture  tends  to  flatten  out  the  skull  over  the  area  where  the  violence 
is  applied,  and  is  like  bending  a  barrel  hoop  so  as  to  straighten  it.  Like 
the  barrel  hoop,  it  gives  way  first  on  the  inner  or  concave  surface,  and  if 
the  force  is  not  continued  this  surface  alone  may  be  broken.  For  the 
same  reason,  in  complete  fractures  the  inner  table  is  fractured  first.  In 
addition  this  inner  table  is  most  extensively  fractured  in  most  cases,  for  (1) 
it  is  thinner  and  more  brittle  (hence  called  the  "vitreous  table");  (2)  the 
force  as  it  travels  from  the  outer  table  through  the  diploe  to  the  inner 
table  passes  in  a  radiating  manner  so  as  to  reach  the  inner  plate  in  a  more 
diffused  form;  (3)  the  inner  table  is  a  part  of  a  smaller  circle;  and  (4)  as 
the  force  tends  to  flatten  out  the  arch,  the  bony  particles  of  the  outer  table 

1  Dupluy  and  Recluo,  vol    iii,  p    461. 


THE  HEAD  31 

are  compressed  together  and  those  of  the  inner  table  are  forced  asunder, 
as  in  straightening  a  bar. el  hoop  over  the  knee.  Owing  to  its  elasticity, 
the  outer  table  recoils  after  the  injury,  diminishing  its  depression,  while 
the  inner  table  remains  more  depressed  on  account  of  its  inelasticity. 

In  general,  fracture  of  the  vault  occurs  from  a  given  violence  when  the 
limit  of  its  elasticity  is  exceeded,  as  illustrated  in  the  straightening  of  a 
barrel  hoop.  Fractures  of  the  vault  are  cine  to  direct  violence,  and  usually 
occur  at  the  point  where  the  force  is  applied.  "When  a  considerable 
force  is  applied  over  a  limited  area,  this  area  of  the  skull  is  usually 
depressed.  When  it  is  applied  over  a  large  surface  (as  in  falls  from  a 
height),  the  entire  globe  of  the  skull  is  compressed  or  flattened  in  the 
direction  in  which  the  force  acts,  and  lengthened  or  pulled  apart  in  a  direc- 
tion at  right  angles  to  this.  Two  forms  of  fracture  may  result:  (1)  a 
"compression  fracture"  at  the  point  where  the  skull  is  pressed  together 
by  the  direct  violence;  and  (2)  a  "bursting  fracture,"  where  the  skull  has 
been  lengthened  and  forced  asunder.  The  latter  form  is  due  to  indirect 
violence,  and  occurs  more  often  at  the  base  than  on  the  vault  of  the  skull. 

Symptoms. — The  symptoms  and  danger  of  fractures  of  the  vault 
depend  very  largely  on  the  concomitant  brain  lesions:  (1)  concussion; 
(2)  contusion  of  the  brain;  and  (3)  intracranial  hemorrhage.  Fractures 
of  the  temporal  region  are  in  general  more  serious  than  similar  fractures 
of  the  rest  of  the  vault,  for  the  middle  meningeal  artery  is  often  injured, 
and  the  resulting  hemorrhage  causes  compression  of  the  brain.  The 
escape  of  cerebrospinal  fluid  from  a  fracture  of  the  vault  is  not  common, 
though  it  has  been  observed  in  compound  fractures  and  in  simple  frac- 
tures in  children  (resulting  in  a  fluctuating  tumor  beneath  the  scalp). 
It  indicates  injury  of  the  dura. 

It  is  interesting  to  note  how  the  construction  of  the  skull  resists  the 
fracturing  force  in  many  ways.  A  blow  on  the  vertex  in  the  parietal 
region  tends  to  drive  the  upper  borders  of  the  parietal  bones  inward 
and  the  lower  borders  outward.  The  latter  tendency  is  resisted  by 
the  overlapping  great  wing  of  the  sphenoid  and  the  squamous  bone. 
The  latter  is  buttressed  by  the  zygomatic  arch  and  this  in  turn  by  the 
malar  and  the  bones  of  the  face,  hence  the  pain  in  the  face  said  to  be 
felt  in  falls  or  blows  on  the  top  of  the  head.  When  the  frontal  suture 
exists,  a  tendency  of  the  lower  part  of  the  frontal  bone  to  be  forced  out- 
ward in  blows  on  the  median  parts  of  the  frontal  is  similarly  resisted 
by  the  overlapping  anterior  inferior  part  of  the  parietal  and  the  great 
wing  of  the  sphenoid.  A  blow  on  the  upper  part  of  the  frontal  bone  is 
transmitted  to  the  parietal,  on  which  this  part  of  the  frontal  bone  rests, 
owing  to  the  bevelling  of  the  upper  part  of  the  coronary  suture.  Blows 
on  the  occiput  are  less  safeguarded  by  anatomical  arrangements,  except 
articulation  with  the  elastic  vertebral  column.  Gaseous  tumors 
beneath  the  scalp  have  been  described  as  a  sequel  to  fractures  of  the 

-Lull  in  which  one  of  the  cavities  containing  air  has  been  involved  in  the 
fracture,  i.  <■.,  the  various  sinuses,  mastoid  cells,  i-tt\ 

Fractures  of  the  Base.  Fractures  of  the  base  may  be  due  to  (I )  direct 
violence,    2)  indirect  violence,  and  (3)  extension  of  a  fracture  of  the 


32  THE  HEAD  AND  NECK 

vault.  Fractures  of  the  base  by  direct  violence  occur  in  cases  where  a 
foreign  body  is  forced  through  the  orbital,  nasal,  or  pharyngeal  roof,  or 
through  the  nape  of  the  neck  in  the  posterior  fossa.  They  are  not  com- 
mon. One  form  of  fracture  of  the  base  by  indirect  violence  is  illustrated 
by  the  fracture  of  the  cribriform  plate  of  the  ethmoid  or  the  orbital  plate 
of  the  frontal  by  a  blow  on  the  root  of  the  nose  or  the  lower  part  of  the 
frontal  bone;  and  by  the  fracture  of  the  glenoid  fossa  by  the  condyle  of 
the  jaw  driven  violently  upward,  as  in  falls  or  blows  on  the  chin.  In  this 
manner  the  condyle  has  been  actually  thrust  into  the  cranial  cavity 
(Chassaignac).  Again,  in  falls  upon  the  buttocks,  less  often  upon 
the  feet  or  knees,  the  force  has  been  transmitted  along  the  vertebral 
column,  especially  when  it  is  kept  rigid  by  muscular  action,  and  has 
resulted  in  the  fracture  of  the  base  in  the  occipital  region,  often  in  a 
"ring  fracture"  around  the  foramen  magnum.  A  similar  fracture  may 
possibly  result  from  a  blow  on  the  head  just  as  the  handle  of  a  hammer 
may  be  driven  in  either  by  a  blow  on  the  end  of  the  handle  or  by  one  on 
the  head  of  the  hammer. 

Mechanism. — The  mechanism  of  the  majority  of  fractures  of  the  base 
has  been  much  discussed.  The  former  theory  that  many  were  the  result  of 
contrecoup,  or  a  focussing  of  the  force  at  the  opposite  pole  to  that  struck, 
has  been  abandoned.  Possibly  a  very  few  cases  may  be  so  explained, 
though  perhaps  better  as  "bursting"  fractures.  Aran  and  others  showed 
that  many  fractures  of  the  base  were  fractures  by  irradiation,  i.  e.,  the  result 
of  fractures  of  the  vault  spreading  to  the  base  by  the  shortest  route  irre- 
spective of  the  sutures;  hence  fractures  of  the  frontal  region  spread  to  the 
anterior  fossa,  those  of  the  parietal  region  to  the  middle  fossa,  and  those 
of  the  occipital  region  to  the  posterior  fossa.  This  was  especially  the 
case  in  linear  fissures,  the  result  of  diffused  violence,  as  in  falls  upon  the 
head.  In  general,  when  the  violence  is  not  excessive,  Felicet  found  that 
these  fractures  seem  to  run  in  the  weaker  areas  between  the  ridges  or 
buttresses  (see  p.  29).  These  explanations  do  not  fit  all  cases,  or  even  the 
majority,  as  well  as  does  that  of  "bursting"  fractures  (see  p.  31).  As  seen 
above,  the  latter  are  indirect  fractures  and  probably  comprise  most  of  the 
fractures  of  the  cranial  base.  Fractures  due  to  bursting  (i.  e.,  most 
fractures  of  the  base)  run  parallel  to  the  axis  of  pressure,  those  due  to 
compression  run  at  right  angles  to  this  axis.  As  fractures  of  the  base  run 
in  the  direction  of  the  violence  that  inflicts  the  injury,  or  parallel  to  it,  we 
can  fairly  well  predict  the  course  of  a  fracture  of  the  base  if  we  know  the 
direction  of  the  force  and  the  point  struck.  Bursting  fractures  are  most 
likely  to  occur  where  the  skull  is  weakest,  which  is  at  the  base,  owing  to 
the  numerous  foramina,  etc.  (see  Figs.  3  and  4).  The  thin  orbital  plate 
and  occipital  bone  and  the  thicker  petrous  bone,  weakened  by  its  fora- 
mina and  canals,  are  the  parts  most  often  fractured. 

In  fractures  of  the  base  there  is  usually  an  escape  of  blood  and  often  of 
cerebrospinal  fluid  externally.  As  the  weakest  part  of  the  petrous  bone 
is  generally  involved,  which  lies  in  the  plane  passing  through  the  middle 
ear,  the  internal  ear,  and  the  internal  auditory  meatus,  the  tympanic 
membrane  is  commonly  ruptured,  and  this  allows  of  the  escape  of  blood 


PLATE  I 


FIG.  3 


Illustrating  Lines  of  Bursting  Force  in  Basal  Fractures. 

(Wahl.) 


FIG.  5 

SUP.    LONGITUDINAL      ,  N  F.    LONGITUDINAL 
SINUS  ! /  SINUS 


SPHENOPA 
RIETAL 
SINUS 


INF.    PETRO- 
SAL   SINUS 

SUP.    PETRO- 
SAL   SINUS 


Interior  of  the  Base  of  the  Skull  Covered  by  Dura,  showing 
the  sinuses,  nerwe  exits,  and  tentorium.  Cranial  nerves  are 
numbered  in   Roman  figures.     (Merkel.) 


THE  HEAD  33 

from  the  ear,  a  symptom  so  common  in  fractures  of  this  region  of  the  base. 
This  blood  may  l>e  derived  from  the  vessels  of  the  tympanum  and  its 
membrane  or  from  an  intracranial  source,  sometimes  from  the  rupture 
of  one  of  the  sinuses  about  the  petrous  bone.  Hence  the  escape  of  blood 
does  not  prove  the  existence  of  a  fracture.  If  the  membrane  is  not  rup- 
tured the  blood  may  pass  through  the  Eustachian  tube  and  escape  at  the 
nose  or  mouth.  In  addition  to  bleeding  from  the  ear  the  flow  of  cere- 
brospinal fluid  is  sometimes  observed.  This  occurs  when  the  dura  and 
arachnoid,  or  their  tubular  prolongation  in  the  internal  auditory  meatus, 
are  torn  by  the  fracture,  which  connects  the  subarachnoid  space  with  the 
tympanum,  whose  membrane  is  lacerated.  In  fractures  of  the  base  of  the 
skull  one  of  the  cranial  nerves  may  be  injured  and  paralyzed.  The  facial 
is  the  nerve  most  often  involved  alone  or  together  with  the  auditory. 

In  fractures  of  the  anterior  fossa  the  blood  escapes  into  the  nose, 
mouth,  or  orbit.  In  the  latter  case  it  produces  a  subconjunctival  ecchy- 
mosis,  rarely  an  exophthalmos.  Bleeding  into  the  nose  may  run  back 
into  the  mouth,  and  in  bleeding  either  into  the  mouth  or  nose  the  blood 
may  be  swallowed  and  subsequently  vomited.  When  bleeding  from  the 
nose  or  mouth  occurs  as  the  result  of  a  basal  fracture,  the  latter  involves 
the  cribriform  plate  or  the  body  of  the  sphenoid.  In  bleeding  from  the 
nose  the  greater  part  of  the  blood  probably  comes  from  the  torn  mucosa 
of  the  nasal  roof.  If  there  is  a  discharge  of  cerebrospinal  fluid  from  the 
nose  there  must  be  a  laceration  of  the  nasal  mucosa  and  of  the  dura  and 
arachnoid.  In  fracture  of  the  base  in  the  posterior  fossa  of  the  skull  the 
blood  may  appear  as  an  extravasation  about  the  mastoid  process  or  the 
nape  of  the  neck. 

Symptoms. — The  symptoms  and  serious  nature  of  basal  fractures  depend 
upon  the  concomitant  intracranial  lesions.  Meningitis,  due  to  infection 
of  a  fracture  of  the  base  which  opens  into  a  cavity  connected  with  the 
air,  is  rare  as  a  cause  of  death  as  compared  with  the  intracranial  lesions 
due  to  the  injury.  The  base  of  the  skull  is  rather  inaccessible  to  opera- 
tions on  account  of  its  location. 

Owing  to  a  lack  of  reparative  vitality,  repair  after  fractures  of  the 
skull  is  very  slow  and  bony  union  occurs  only  when  the  fragments  are 
separated  by  a  very  small  interval.  The  new  bone  is  produced  mostly 
by  the  diploe  and  more  by  the  dura  than  by  the  pericranium.  When 
there  is  any  considerable  loss  of  substance  the  opening  is  not  filled  in 
with  bone  save  for  a  oarrow  strip  around  the  edge.  After  recovery  from 
diastasis  in  a  child  the  growth  of  bone  is  not  interfered  with. 


The  Contents  of  the  Cranium. 

The  Cerebral  Membranes.  The  tough  fibrous  dura  may  be  divided 
into  an  outer  periosteal  layer  and  an  inner  or  supporting  layer.  This  cor- 
responds to  its  twofold  function,  on  the  one  hand  as  a  periosteum,  and 
on  the  other  ;i-  ;i  protective  covering  of  the  brain.  These  layers  are 
inseparable  over  the  greater  part  of  their  extent,  hut  the  inner  separates 


34  THE  HEAD   AND  NECK 

from  the  outer  layer  to  form  the  cranial  sinuses  and  the  'processes,  like 
the  falx  and  tentorium,  which  help  to  support  and  protect  the  brain 
(see  Fig.  1). 

The  adhesion  of  the  outer  layer  to  the  bone  is  firmer  in  children  than  in 
adults,  but  after  middle  life  it  increases  with  age.  Hence  extradural 
hemorrhage  is  rare  in  children.  In  chronic  inflammation  of  the  bone  or 
the  dura  it  becomes  more  adherent,  but  is  less  so  in  acute  inflammations. 
It  varies  in  different  parts  of  the  skull.  Over  the  vertex  and,  according  to 
Tillaux,  particularly  in  the  temporal  fossa?  the  dura  is  comparatively 
loosely  attached,  except  along  the  sutures,  where  it  is  more  adherent. 
This  loose  attachment  allows  a  probe  to  be  passed  a  considerable  distance 
between  the  bone  and  the  dura,  if  the  sutures  are  avoided,  and  large 
extravasations  of  blood  or  pus  may  occur  here  and  lead  to  compression  of 
the  brain.  Such  extravasations  are  often  limited  to  one  bone  by  the 
adhesion  along  the  suture  lines,  but  not  necessarily,  especially  in  the  case 
of  purulent  collections.  The  adhesion  of  the  dura  to  the  bone  is  largely 
due  to  the  passage  of  small  bloodvessels  from  the  meningeal  vessels  of  the 
former  to  nourish  the  bone.  The  bone  can  live,  however,  if  the  dura  is 
stripped  off  and  loss  of  bone  is  not  repaired  by  the  dura.  In  the  majority 
of  traumatic  cases  the  cause  of  cerebral  compression  lies  outside  the  dura 
in  the  epidural  space  or  is  due  to  the  bone  itself. 

As  pointed  out  by  Sir  C.  Bell,  the  dura  of  the  vault  may  be  separated 
from  the  bone  by  a  blow,  and  if  this  occurs  during  life  the  corresponding 
epidural  area  is  occupied  by  a  clot  from  the  rupture  of  many  small  vessels 
that  pass  from  the  dura  to  nourish  the  bone.  If  a  larger  vessel  is  ruptured, 
the  hemorrhage  may  gradually  strip  off  more  and  more  of  the  dura,  so 
that  a  clot  is  formed  which  gradually  causes  local  or  general  symptoms 
of  compression.  The  stripping  up  of  the  dura  may  be  demonstrated  on  the 
cadaver  by  striking  a  blow  and  then  injecting  the  bloodvessels. 

The  vessel  which  by  its  rupture  is  most  often  (85  per  cent,  more  or  less) 
the  cause  of  serious  or  fatal  epidural  compression  is  the  middle  meningeal 
artery  in  the  temporal  fossa.  This  is  the  cause  of  the  more  serious 
results  of  fracture  in  this  region.  This  vessel  is  for  the  most  part  closely 
wrapped  by  the  outer  layer  of  the  dura  so  that  it  is  ruptured  in  any  tear 
of  the  latter,  in  fracture  of  the  skull.  It  may  also  be  torn  without  frac- 
ture, for  in  the  great  wing  of  the  sphenoid  and  the  antero-inferior  angle 
of  the  parietal  it  is  often  lodged  in  a  bony  canal  or  a  groove  whose  open 
side  is  smaller  than  the  artery,  so  that  if  by  a  blow  the  dura  is  here  stripped 
from  the  bone  the  artery  is  torn  at  the  point  where  the  canal  or  deep 
groove  prevents  it  from  being  stripped  back  with  the  dura.  When  after 
a  blow  over  the  position  of  this  vessel  symptoms  of  compression,  not  pres- 
ent at  first,  come  on  after  an  interval  and  gradually  increase,  rupture  of 
this  artery  or  some  of  its  branches  is  probable.  The  "free  interval"  is 
due  to  the  escape  under  pressure  of  the  cerebrospinal  fluid  into  the  spinal 
canal,  so  that  the  hemorrhage  does  not  seriously  increase  the  intracranial 
pressure  for  a  time.  As  it  lies  in  part  over  or  close  to  the  cortical  motor 
area,  motor  paralyses  are  likely  to  occur  from  local  compression.  As  such 
cases  commonly  get  progressively  worse  and  end  fatally,  operation  with 


THE  HEAD  35 

turning  out  the  clot  and  plugging  or  tying  the  vessel  is  imperatively 
demanded. 

Hence  the  importance  of  knowing  the  position  and  course  of  this  vessel 
(see  Fig.  9).  The  trunk  of  the  artery  passes  outward  and  forward  for  a 
short  but  variable  distance  from  the  foramen  spinosum,  through  which 
it  enters  the  skull  and  about  corresponds  externally  with  the  middle  of 
the  zygoma.  It  has  two  main  branches,  of  which  the  larger  anterior  one 
runs  upward  and  forward  across  the  antero-inferior  angle  of  the  parietal 
bone  and  continues  in  a  groove  a  little  behind  the  coronal  suture,  giving 
off  branches  which  run  upward  and  backward.  The  posterior  branch 
runs  backward  across  the  squamous  bone  and  then  upward  and  backward 
over  the  posterior  part  of  the  parietal  bone.  Although  it  may  be  possible 
by  a  single  trephine  opening  to  expose  both  branches  of  the  artery,  yet 
such  an  opening  must  be  low  down  in  the  temporal  fossa  and  below  the 
common  site  of  injury  of  the  vessel,  which  is  in  the  anterior  branch  near 
the  pterion,  where  the  groove  is  often  very  deep  or  converted  into  a  canal. 
When  the  groove  is  so  arranged  fracture  here  without  laceration  of  the 
artery  would  hardly  be  possible,  and  this  thin  part  of  the  skull  is  par- 
ticularly liable  to  be  fractured.  If  we  trephine  and  ligate  the  artery  too 
low,  below  the  point  of  rupture,  an  anastomotic  branch  from  the  orbit 
may  join  the  artery  above  the  point  of  ligation  and  thus  continue  the 
hemorrhage. 

To  expose  the  anterior  branch  of  the  middle  meningeal  artery  a  trephine 
opening  or  bone  flap  is  made  just  behind  the  pterion  (see  p.  26) ;  or  two 
fingers'  breadth  above  the  zygoma  and  a  thumb's  breadth  behind  the 
Frontal  process  of  the  malar  bone  (Vogt);  or  3  to  4  cm.  (lj  to  1£  in.) 
behind  the  latter  point  on  a  level  with  the  supra-orbital  margin;  or  at  the 
intersection  of  a  vertical  line  drawn  through  the  middle  of  the  zygoma 
and  a  horizontal  line  through  the  supra-orbital  margin  (Kronlein).  As 
the  artery  lies  enclosed  in  the  firm  dura  or  in  the  bone,  the  chance  of 
spontaneous  arrest  of  bleeding  is  slight. 

At  the  base  of  the  skull  the  dura  is  closely  adherent  to  the  bone,  so  that 
epidural  extravasation  can  scarcely  occur,  and  in  fractures  of  the  base 
the  dura  is  likely  to  be  torn,  allowing  the  escape  of  cerebrospinal  fluid. 
The  dura  smooths  over  some  of  the  inequalities  of  the  base  and  passes 
out  through  the  foramina  of  the  skull  with  the  cranial  nerves  to  become 
continuous  with  the  nerve  sheaths  as  well  as  with  the  pericranium  on  the 
outer  surface  of  the  skull.  Along  these  prolongations  infection  may 
spread  from  the  surface  to  the  cavity  of  the  skull.  When  the  dura  is 
exposed  during  life  observe  its  pulsation,  synchronous  with  the  respiration 
and  due  to  the  rise  and  fall  in  the  blood  pressure  of  the  brain  during  expi- 
ration and  inspiration  respectively.  If  this  pulsation  is  absent,  it  indicates 
an  increase  of  the  intracranial  pressure  due  lo  intracranial  tumor,  abscess, 
hemorrhage,  etc.  The  sensory  nerves  of  the  dura  are  derived  largely 
from  filaments  of  the  trigeminal  nerve.  The  inner  surface  of  the  dura  is 
smooth,  owing  to  the  layer  of  flat  endothelial  cells  which  covers  it. 

The  Subdural  Space.  The  subdural  space,  or  the  potential  interval 
between  the  dura  and  the  arachnoid,  contains  ;i  small  amount  of  fluid 


36  THE  HEAD  AND  NECK 

and  probably  serves  to  prevent  friction  between  the  skull  and  the  brain 
during  its  movements,  like  the  pleural  and  other  serous  sacs.  The  hemor- 
rhage in  pachymeningitis  interna  occurs  in  this  space,  into  which  a  consid- 
erable effusion  may  occur  without  marked  symptoms,  on  account  of  its 
wide  diffusion.  Following  an  injury  extravasations  of  blood  into  this  space 
are  common,  and  the  blood  so  effused  is  liable  to  shift  its  position  and 
perhaps  suddenly  cause  dangerous  pressure  symptoms  by  gravitating  to 
the  vicinity  of  the  pons,  cerebellum,  and  medulla.  Similarly,  during 
operations  upon  the  brain,  blood,  pus,  or  irrigating  fluid  may  enter  this 
space  and  gravitate  toward  the  medulla  or  spinal  canal.  Hence  care 
should  be  taken  in  evacuating  and  irrigating  cerebral  abscesses  to  avoid 
the  passage  of  the  fluid  into  this  space  and  to  secure  its  escape  extra- 
cranially.  The  subdural  space  communicates  with  the  abundant  lym- 
phatics of  the  dura,  and  from  the  latter  pathogenic  organisms  may  invade 
this  space.  This  space  is  continuous,  through  the  foramen  magnum, 
with  the  subdural  space  of  the  cord  so  that  infection  may  rapidly 
spread  along  it  in  either  direction.  Normally,  the  inner  surface  of  the  dura 
is  not  connected  with  the  arachnoid  except  by  a  few  and  very  delicate 
processes,  hence  on  opening  the  dura  any  adhesions  which  prevent  the 
probe  or  finger  passing  freely  between  it  and  the  brain  are  pathological. 
The  fibrous  folds  formed  by  the  reflection  of  the  inner  or  protective 
layer  of  the  dura  (falx  cerebri,  tentorium  cerebelli,  etc.)  are  of  little  sur- 
gical interest,  but  they  are  important  in  preventing  the  compression 
of  the  two  hemispheres  by  each  other,  and  of  the  isthmus  of  the  brain 
and  the  cerebellum  by  the  cerebrum. 

The  Sinuses  of  the  Dura. — The  sinuses  of  the  dura  are  formed  by  the 
separation  of  its  inner  from  its  outer  layer  on  the  surface  or  by  the  separa- 
tion of  two  folds  of  the  inner  layer  in  the  folds  or  processes  of  the  dura 
(see  Fig.  1).  They  are  lined  by  an  epithelial  layer  continuous  with  the 
inner  layer  of  the  veins.  Their  walls  are  rigid  and  non-collapsible,  so  that 
when  wounded  bleeding  is  not  spontaneously  arrested.  Certain  sinuses 
are  of  especial  surgical  interest,  and  their  position  is  of  importance  because 
in  certain  operations  we  wish  to  avoid  them,  in  others  to  expose  them 
(see  Figs.  5  and  6).  Owing  to  their  relations  to  the  skull  some  of  them 
are  liable  to  be  injured  in  fractures  of  the  skull. 

The  superior  longitudinal  or  sagittal  sinus  extends  in  the  median  line 
from  the  foramen  cecum  anteriorly  to  the  torcular  Herophili,  opposite 
the  external  occipital  protuberance,  posteriorly.  As  the  torcular  is  usually 
to  the  right  of  the  median  line,  the  posterior  and  larger  part  of  the  sinus 
is  also  rather  more  to  the  right  of  the  median  line.  Through  the  foramen 
cecum  it  communicates  with  the  veins  of  the  nasal  mucosa,  hence  epistaxis 
may  directly  relieve  cerebral  congestion,  and  infectious  organisms  from 
lesions  of  the  nasal  septum  may  thus  enter  the  sinus.  It  also  communi- 
cates with  the  scalp  by  the  emissary  veins  passing  through  the  parietal 
foramina,  so  that  it  may  become  infected  from  erysipelas  or  other 
septic  diseases  of  the  vertex.  This  sinus  receives  the  veins  from  the 
median  and  upper  surface  of  the  cerebrum  and  communicates  with  the 
basal  sinuses  through  the  anastomosis  of  the  superior  cerebral  with 


THE  HEAD 


37 


the  middle  cerebral  and  Sylvian  veins.     As  the  blood  of  the  superior 
longitudinal  sinus  usually  passes  into  the  right  lateral  sinus,  and  that 


Fig.  6 


bowing  their  oommunioationa  with  tlu;  extracranial  veins. 
i  p. in   Uaoewen.) 


38  THE  HEAD  AND  NECK 

of  the  straight  sinus  into  the  left  lateral  sinus,  it  follows  that  the  right 
lateral  sinus  is  usually  the  larger  and  receives  the  blood  from  the  surface 
of  the  brain,  while  the  left  sinus  drains  the  central  ganglionic  portions. 

The  course  of  the  lateral  sinuses  is  represented  by  a  line  from  the 
external  occipital  protuberance  to  the  upper  margin  of  the  external 
osseous  meatus  or  the  base  of  the  mastoid  process  (see  Fig.  9).  It  is 
usually  slightly  convex  upward  and  crosses  the  asterion,  from  whence  to 
the  jugular  foramen  it  is  called  the  sigmoid  sinus,  on  account  of  its  crooked 
S-shaped  course.  The  sharp  downward  and  inward  bend,  or  genu,  of 
the  sigmoid  sinus  on  the  mastoid  bone  is  convex  forward.  It  reaches 
forward  to  a  point  3  to  12  mm.  (-g-  to  \  in.)  behind  a  coronal  plane  through 
the  posterior  border  of  the  external  osseous  meatus,  and  its  upper  limit  is 
on  a  level  with  the  upper  part  of  the  meatus.  The  genu  on  the  right  side 
extends  slightly  farther  forward  and  outward  than  on  the  left,  and  this 
fact  may  possibly  account  for  the  supposed  greater  frequency  of  intra- 
cranial complications  following  otitis  media  on  the  right  side.  The  genu 
of  the  sigmoid  sinus  receives  groups  of  veins  from  the  tympanum  and 
the  mastoid  antrum  and  cells,  through  which  infection  may  spread  to 
the  sinus  and  cause  thrombosis. 

The  course  of  the  sigmoid  sinus,  where  it  is  accessible  to  operation, 
corresponds  to  two  lines;  the  upper  and  more  superficial  part  to  the 
posterior  §  of  a  line  from  the  asterion  to  the  upper  margin  of  the  external 
osseous  meatus,  the  vertical  part  to  the  upper  §  of  a  line  from  the  parieto- 
squamomastoid  junction  (or  the  middle  of  the  base  of  the  mastoid)  to 
the  tip  of  the  mastoid  (see  Fig.  9).  An  opening  may  be  made  into  the 
genu,  the  part  of  the  sinus  most  often  affected,  at  a  point  12  mm.  (%  in.) 
behind  the  posterior  wall  of  the  bony  auditory  canal  between  the  levels 
of  its  roof  and  floor.  Between  these  levels  the  upper  and  more  superficial 
part  of  the  sinus  is  6  mm.  (J  in.) — sometimes  as  little  as  2  mm.  (y1-^  in.) — 
from  the  surface,  and  is  thus  more  superficial  than  the  antrum,  while  its 
lower  part  lies  more  deeply. 

The  sigmoid  sinus  is  connected  with  the  surface  veins  through  two 
emissary  veins,  the  mastoid  and  the  posterior  condylar.  The  mastoid 
vein  joins  the  occipital  and  through  this  the  deep  cervical,  or  occasionally 
it  joins  the  posterior  auricular.  It  may  become  thrombosed  from  sinus 
thrombosis,  or  its  foramen  may  give  vent  to  extradural  pus  in  the  cere- 
bellar fossa.  According  to  Macewen,  the  posterior  condylar  vein  is  the 
larger  and  more  constant  of  the  two,  contrary  to  what  is  usually  stated. 
It  joins  the  deep  veins  at  the  back  of  the  neck,  and  its  foramen  may  drain 
extradural  pus  in  the  bottom  of  the  cerebellar  fossa,  setting  up  a  deep 
inflammation  or  abscess  in  the  upper  part  of  the  back  of  the  neck,  which 
causes  swelling  and  tenderness  on  pressure  here.  In  septic  sinus  throm- 
bosis these  two  emissary  veins,  as  well  as  the  occipital  sinus,  may  convey 
infective  matter  from  the  lateral  and  sigmoid  sinuses  to  the  heart  and 
lungs,  so  that  ligation  of  the  internal  jugular  vein  does  not  afford  com- 
plete protection  against  this  accident. 

The  upper  and  posterior  end  of  the  sigmoid  sinus  lies  at  the  junction 
of  the  middle  and  anterior  thirds  of  the  cerebellum,  so  that  the  latter 


THE  HEAD  39 

may  be  exposed  in  front  of  the  sinus,  though  preferably  behind  it.  The 
parietosquamomastoid  junction  corresponds  to  the  point  where  the  superior 
petrosal  joins  the  sigmoid  sinus  and  where  the  upper  border  of  the  petrous 
joins  the  mastoid  bone. 

The  Cavernous  Sinus. — The  cavernous  sinus,  extending  from  the  sphe- 
noidal fissure  to  the  apex  of  the  petrous  bone,  receives  and  is,  as  it  were, 
the  continuation  of  the  ophthalmic  reins.  The  fact  that  the  latter  anas- 
tomose with  the  facial  vein  explains  why  an  inflammation  near  the  facial 
vein,  like  a  carbuncle  of  the  upper  lip,  is  more  serious  than  a  similar 
condition  on  the  lower  lip,  as  the  former  may  extend  along  the  veins  as  a 
periphlebitis  and  set  up  a  cavernous  sinus  thrombosis.  This  sinus  also 
communicates  with  the  pterygoid  plexus  by  means  of  the  ophthalmic  and 
Vesalian  veins,  through  which  septic  material  may  pass  from  one  to  the 
other.  The  intimate  relation  between  the  carotid  artery  and  the  cavernous 
sinus  accounts  for  the  fact  that  arteriovenous  aneurysm  has  followed 
injury  of  these  parts.  In  such  cases  the  orbital  cavity  is  distended  with 
a  pulsating  tumor  consisting  of  the  dilated  ophthalmic  veins  which 
protrude  the  eyeball. 

As  the  dural  sinuses  are  rigid,  non-collapsible,  ever-patent  tubes,  and 
the  jugular  veins  into  which  they  empty  are  alternately  distended  in 
expiration  and  collapsed  in  inspiration,  this  aspiration  would  involve 
the  sinuses  unless  there  were  some  mechanism  to  prevent  it.  If  the 
sinuses  were  thus  aspirated  and  the  blood  of  the  brain  suddenly  pro- 
pelled forward  to  compensate  for  that  withdrawn,  there  would  be  a 
disturbance  of  brain  function,  a  sudden  faintness  or  lack  of  brain  power 
on  each  deep  inspiration.  The  entire  sinus  arrangement  insures  a  regular 
even  flow  as  seen  in  the  entrance  of  the  middle  and  posterior  cerebral 
veins  obliquely  into  the  longitudinal  sinus  against  its  current,  thus 
damming  it  back,1  and  especially  in  the  trap-like  passage  of  the  sigmoid 
sinus  into  the  jugular  bulb.  The  roof  of  the  lowest  portion,  near  the  end 
of  the  sigmoid  sinus,  is  on  or  below  the  level  of  the  floor  of  its  entrance 
into  the  jugular  bulb,  and  the  roof  of  the  latter  is  much  above  the  whole 
of  the  lower  end  of  the  sigmoid  sinus,  so  that  an  arrangement  like  a 
plumber's  trap  is  formed  to  prevent  aspiration  of  the  sinus.  By  the 
entrance  of  the  inferior  petrosal  sinus  directly  into  the  jugular  bulb  (so 
that  this  sinus  alone,  if  any,  would  feel  the  effects  of  aspiration),  and 
by  pouring  its  blood  into  the  jugular  bulb  from  a  large  reservoir,  the 
cavernous  sinus,  there  is  no  absolute  collapse  of  the  internal  jugular  with 
the  consequent  difficulty  of  reestablishing  the  flow. 

Between  the  two  layers  of  the  dura,  and  occupying  a  depression  on  the 
upper  surface  of  the  apex  of  the  petrous  bone,  and  the  adjoining  cartilage 
filling  the  middle  lacerated  foramen,  is  the  crescentic  Gasserian  ganglion. 
When  the  failure  of  peripheral  operations  for  tic  douloureux  or  its  in- 
volvement of  two  or  more  divisions  of  the  nerve  shows  extensive  central 
involvement,  this  ganglion  is  to  be  removed  or  its  sensory  roof   resected. 

further  interesting  particulare,  conroll   Maoewen,  Diara  ea  of  t  lt<-  Brain  and  Spinal  Cord, 


40 


THE  HEAD  AND  NECK 


The  best  methods  of  exposure  are  the  osteoplastic  Hartley-Krause  method, 
by  which  an  J2-shaped  flap  of  bone  and  soft  parts,  having  its  base  on  a 
level  with  the  zygomatic  arch,  is  turned  down,  exposing  the  dura,  or 
Cushing's  method,  in  which  the  zygoma  is  temporarily  or  permanently 
resected  and  the  skull  opened  at  a  lower  level.  The  latter  is  to  be  pre- 
ferred because  it  involves  less  danger  of  injury  to  the  brain,  from  the 
pressure  of  the  retractors,  and  to  the  middle  meningeal  artery.  The  dura 
is  then  separated  from  the  floor  of  the  middle  fossa  of  the  skull  until  the 
second  and  third  divisions  of  the  nerve  are  exposed  and  traced  up  to  the 
ganglion.  To  expose  the  latter  the  outer  layer  of  the  dura  must  be 
divided.  Its  close  relation  to  the  internal  carotid  artery,  the  cavernous 
sinus,  and  the  third,  fourth,  and  sixth  nerves  must  be  borne  in  mind, 
but  especially  its  relation  to  the  middle  meningeal  artery,  which  enters 


Fig.  7 


Cushing's  exposure  of  the  Gasserian  ganglion.      (Kocher,  after  Cushing.) 

the  skull  just  behind  its  inferior  maxillary  division.  The  latter  artery 
may  also  give  trouble  in  the  bone  flap.  A  small  vessel  accompanying  the 
inferior  maxillary  nerve  has  occasionally  caused  troublesome  hemorrhage. 
As  it  is  often  a  matter  of  great  difficulty  to  remove  the  entire  ganglion,  the 
sensory  root  has  been  severed  or  avulsed  instead.  In  this  operation  the 
motor  root  and  branches  of  the  ganglion  are  preserved. 

The  delicate  arachnoid  is  closely  applied  to  the  pia  over  the  top  and 
sides  of  the  head,  but  does  not  dip  in  between  the  convolutions.  Over 
the  surface  of  the  convolutions  the  two  membranes  cannot  be  separated, 
and  must  be  considered  as  one,  the  pia-arachnoid.  The  so-called  sub- 
arachnoid space,  which  is  a  system  of  intercommunicating  clefts  partly 
separated  by  the  meshes  of  the  pia-arachnoid,  is  scarcely  recognizable 
over  the  upper  surface,  though  present,  while  over  the  posterior  two- 
thirds  of  the  base  (in  the  posterior  and  middle  fossae)  it  is  capacious  and 


THE  HEAD  41 

contains  the  larger  part  of  the  cerebral  cerebrospinal  fluid.  The  latter 
serves  as  a  water-bed  for  the  important  parts  of  the  brain  resting  upon  it, 
while  the  less  important  frontal  lobes  rest  more  directly  upon  the  bone 
covered  by  dura.  This  arrangement  of  the  fluid  protects  the  posterior 
parts  of  the  base  of  the  brain  from  the  effects  of  injury,  either  direct  or  by 
contrecoup,  while  the  base  of  the  frontal  lobes  is  not  infrequently  injured 
by  coming  in  violent  contact  with  the  irregular  orbital  plates.  The 
cerebrospinal  fluid  differs  from  blood  serum  in  its  very  small  percentage 
of  albumin.  The  cerebral  and  spinal  subarachnoid  spaces  communicate 
freely  with  each  other  through  the  foramen  magnum  and  with  the  cavity 
of  the  cerebral  vesicles  through  the  foramen  of  Magendie  (and  the  fora- 
mina of  Luschka),  in  the  lower  part  of  the  roof  of  the  fourth  ventricle. 
Hence  the  cerebrospinal  fluid  may  also  serve  to  equalize  the  intracranial 
pressure,  by  being  partly  forced  out  from  the  ventricles  through  these 
foramina,  when  the  nerve  centres  in  the  walls  of  the  ventricles  are  con- 
gested, and  down  into  the  spinal  canal  if  the  general  intracranial  pressure 
is  increased  for  any  cause.  In  case  these  foramina  are  blocked  by  a  tuber- 
culous deposit  or  the  pressure  of  a  cerebellar  tumor,  fluid  may  accumu- 
late in  and  enormously  distend  the  lateral  ventricles  and  result  in  internal 
hydrocephalus.  Lumbar  puncture  as  a  diagnostic  and  therapeutic 
measure  depends  upon  this  intercommunication  and  the  flow  of  the 
cerebrospinal  fluid  from  one  part  to  another.  In  operations  on  the  base 
of  the  brain,  the  cord,  or  on  a  spina  bifida,  etc.,  the  draining  away  of 
cerebrospinal  fluid  may  deprive  the  medulla  of  its  water-bed  and  cause 
it  to  rest  directly  upon  bone,  so  as  even  to  interfere  with  its  functions. 

The  subarachnoid  space  is  continued  around  the  optic  nerve  through 
the  orbit,  where  it  may  even  become  cystic  by  being  shut  off  from  the  rest 
of  the  space.  Over  the  other  cranial  nerves  the  arachnoid  is  continued 
only  a  short  distance  and  becomes  fused  with  the  nerve  sheath,  but  fluid 
injected  into  the  subarachnoid  or  subdural  spaces  passes  along  the  nerves 
as  far  as  the  limbs.  Without  any  direct  channel,  fluid  may  also  pass  from 
the  subarachnoid  to  the  subdural  space  and  even  from  the  former  into  the 
longitudinal  sinus,  through  the  Pacchionian  bodies,  which  are  arachnoid 
villi  and  often  project  into  the  sinus.  The  arachnoid  is  not  considered  as 
an  entity  in  the  pathology  of  meningeal  inflammation. 

The  intimate  relations  of  the  pia  and  brain,  the  former  closely  covering 
the  surface  and  dipping  into  the  substance  of  the  brain  as  an  investment 
of  its  bloodvessels,  shows  that  a  certain  degree  of  encephalitis  is  necessary 
with  leptomeningitis.  The  lymphatics  of  the  pia  open  into  the  sub- 
arachnoid space. 

Little  need  be  said  of  the  brain  itself,  apart  from  the  facts  of  cerebral 
localization  and  craniocerebral  topography,  except  that  surgically  it  is 
;i  large  soft  vascular  mass  that  does  not  completely  fill  the  cranial  cavity, 
and  hence  may  be  injured  by  shaking  or  by  being  thrown  about  and 
colliding  with  the  cranial  walls. 

The  Blood  Supply.-  In  spite  of  the  equalization  of  (he  circulation 
through  the  anastomosing  circle  of  Willis,  ligation  of  a  healthy  common 
carotid  is  generally  followed  by  functional  disturbances  of  the  brain  until 


42  THE  HEAD  AND  NECK 

the  collateral  circulation  is  established,  and  in  about  5  per  cent,  of  cases 
cerebral  softening  and  death  result.  Both  carotids,  however,  have  been 
successfully  ligated  in  a  number  of  cases  with  a  considerable  interval 
between  the  two  operations.  The  effects  of  the  heart's  systole  on  the 
brain  are  diminished  by  the  tortuosities  of  the  arteries  (internal  carotid 
and  vertebral)  before  entering  the  cranial  cavity,  but  the  brain  pulsates 
synchronously  with  the  systole  of  the  heart.  This  pulsation  may  be  seen 
or  felt  on  the  dura  unless  the  intracranial  pressure  is  increased,  when  the 
pulsation  is  diminished  or  absent.  This  pulsation  may  be  transmitted  to 
the  overlying  soft  parts  where  the  bone  is  wanting  on  account  of  injury, 
disease,  or  operation. 

In  the  cerebral  circulation  the  terminal  arteries  of  the  cortex  anas- 
tomose freely,  while  many  of  the  small  basilar  vessels,  in  the  lenticular 
nucleus,  internal  capsule,  optic  thalamus,  etc.,  derived  from  branches  of 
the  middle  cerebral  artery,  have  few  or  no  anastomoses  and  are  prac- 
tically terminal.  Hence  when  the  latter  are  plugged  by  emboli,  which 
are  particularly  apt  to  pass  to  these  vessels,  the  circulation  is  not  restored 
and  coagulation  necrosis  results,  from  blood  stasis  in  a  cone-shaped  area 
having  its  base  on  the  surface.  These  same  vessels  are  also  the  most 
common  source  of  cerebral  hemorrhage,  due  to  the  degeneration  of  the 
vessel's  walls  or  the  formation  of  minute  aneurysms  on  them.  Hence 
the  frequency  of  capsular  lesions. 

The  intracranial  pressure  affects  the  pulse  and  arterial  tension.  With 
gradually  increasing  pressure  the  cerebrospinal  fluid  is  at  first  displaced 
into  the  spinal  canal  and  the  veins  are  narrowed.  As  the  pressure 
increases  it  impedes  the  circulation  in  the  cerebral  veins,  and  to  overcome 
this  the  arterial  tension  is  raised  and  the  pulse  is  slow  and  full.  The 
tension  continues  to  rise  with  increasing  pressure  until  the  obstruction  to 
the  circulation  in  the  brain  is  beyond  the  power  of  the  heart  to  overcome, 
when  the  pulse  becomes  rapid,  the  arterial  tension  is  relaxed,  and  collapse 
and  death  follow.  We  can,  therefore,  measure  the  degree  of  intracranial 
pressure  by  that  of  the  blood  pressure.  Increased  intracranial  pressure 
may  be  relieved  by  trephining.  The  decompression  operation  of 
Cushing,  trephining  beneath  the  temporal  muscle,  is  done  to  arrest  and 
relieve  the  effects  of  increased  intracranial  pressure  when  a  radical 
operation  is  not  feasible.  Wounds  of  the  brain  from  injury  or  operative 
incision  bleed  freely,  but  this  bleeding  is  readily  checked.  The  brain 
weighs  on  an  average  49^  ounces  in  the  male  and  44  ounces  in  the  female. 

Localization  of  Cerebral  Functions.— The  cortical  areas  whose 
function  is  more  or  less  accurately  known  comprise:  (1)  the  motor  area; 
(2)  the  sensory  area;  (3)  the  speech  areas;  (4)  the  visual  areas;  (5)  the 
auditory  area;  (6)  the  area  of  the  sense  of  smell  and  taste.  The  precise 
limit  of  these  areas  is  not  accurately  known,  and  one  area  may  digitate 
into  another.  It  is  most  important  to  know  the  position  of  these  centres 
as  a  guide  in  diagnosticating  and  operating  on  lesions  of  the  cerebral 
cortex  (see  Figs.  6  and  7). 

The  Motor  Area. — Before  the  investigations  of  Sherrington  and 
Griinbaum  this  area  was  thought  to  comprise  the  cortex  of  the  anterior 


THE  HEAD 


42, 


and  posterior  central  convolutions,  bordering  the  fissure  of  Rolando,  and 
the  cortex  immediately  adjacent  to  them,  especially  the  paracentral 
lobule  on  the  mesial  surface.  As  the  result  of  these  observations 
on  the  higher  apes,  confirmed,  in  part  at  least,  by  histological  studies  and 
the  faradization  of  the  human  cortex  in  the  course  of  operations,  the 
motor  area  is  now  thought  to  lie  entirely  in  front  of  the  central  fissure  and 
to  extend  to  the  bottom  of  it  on  its  anterior  surface  only.  In  the  upper 
third  of  the  motor  zone  and  in  the  paracentral  lobule  is  the  area  for  the 
lower  extremity,  in  the  middle  third  that  for  the  upper  extremity,  and 
in  the  lower  third  that  for  the  face  and  tongue  (facial  and  hypoglossal 
nerves).  Between  the  centres  for  the  upper  and  lower  extremities  is  a 
narrow  area  for  the  centre  of  movement  of  fhe  trunk. 


Fig.  8 


Localization  of  function  on  the  cerebral  cortex;   external  surface.      (After  Starr.) 


The  relative  situation  of  the  centres  of  the  several  parts  of  the  extremi- 
ties and  face  is  shown  in  Figs.  Sand  9,  but  their  exact  boundaries  cannot 
be  sharply  defined. 

The  associated  lateral  movements  of  the  eyes  and  the  lateral  movements 
of  the  head  are  controlled  by  the  cortex  of  the  posterior  part  of  the  second 
and  the  posterosuperior  part  of  the  third  frontal  convolution,  irritation  of 
which  causes  conjugate  movements  of  the  head  and  eyes  to  the  opposite 
side. 

The  upper  limit  of  the  motor  area  overlaps  slightly  onto  the  mesial 
mrface,  in  the  paracentral  lobule,  where  the  lower  part  of  the  lower 
extremity  may  be  partly  represented. 

It  is  to  be  remembered  that  each  hemisphere  controls  movements 
mainly  on  the  opposite  aide  of  the  body,  but  to  a  slight  extent  also  on  the 
tame  ride.    This  accounts  for  a  large  amount  of  the  recovery  after 

destruction  of  the  centres  of  one  side,  especially  those  of  the  distal  move- 
ment   of  the  limbs.    This  recovery  is  explained  by  others  by  the  fact  that 


44 


THE  HEAD  AND  NECK 


though  there  is  a  focus  for  the  movement  of  a  particular  part,  like  the 
thumb,  it  is  also  represented  with  diminished  intensity  over  the  sur- 
rounding cortex.  Hence  to  totally  paralyze  a  given  part  a  considerable 
amount  of  cortex  must  be  excised. 

The  sensory  area  is  in  the  parietal  lobe.  The  centre  for  cutaneous 
sensibility  is  in  the  postcentral  gyrus  (and  in  the  limbic  lobe),  that  for 
muscular  sensibility  in  the  inferior  and  superior  parietal  convolutions 
and  the  stereognostic  centre  in  the  superior  parietal  convolution  (Mills). 
These  areas  cannot  be  accurately  outlined  and  their  localization  is  not 
yet  definitely  established. 

The  Speech  Areas. — The  speech  areas,  four  in  number  and  in  kind,  are 
in  the  left  hemisphere  in  right-handed  persons  and  in  the  right  in  left- 
handed  persons.    There  are  two  types  of  aphasia,  which  is  the  loss  of  the 


Fig.  9 


paracentral 
'lodule 


Localization  of  function  on  the  cerebral  cortex;   mesial  surface.      (After  Kocher.) 


power  of  speech,  known  as  motor  and  sensory  aphasia.  The  motor 
speech  centre  lies  in  the  posterior  part  of  the  third  frontal  convolution 
(Broca's  convolution),  just  in  front  of  the  centre  for  the  muscles  of  speech 
(hypoglossal  and  facial  nerve  centres).  A  lesion  of  the  motor  speech 
centre  causes  motor  aphasia,  in  which  there  is  a  loss  of  the  word-forming 
power,  although  the  tongue  is  movable  and  the  patient  may  understand 
spoken  and  written  language  and  knows  what  he  wants  to  say.  It  is  as 
if  the  memory  of  the  motor  combinations  essential  to  produce  speech 
were  lost. 

The  power  of  writing  is  usually  lost  with  motor  speech.  The  probable 
location  of  its  cortical  centre  is  in  the  posterior  part  of  the  second  frontal 
convolution.     Its  loss  is  known  as  agraphia,  a  form  of  motor  aphasia. 

The  auditory  speech  centre  is  in  the  posterior  two-thirds  of  the  first,  and 
perhaps  the  second,  temporal  convolution.    A  lesion  here  causes  "word- 


THE  HEAD  45 

deafness,"  a  sensory  aphasia  in  which  the  memory  of  the  sounds  of  words 
is  lost  so  that  they  are  not  understood,  though  hearing  may  be  normal. 

The  visual  speech  centre  lies  in  the  posterior  part  of  the  angular  gyrus 
in  the  outskirts  of  the  higher  visual  or  the  visuopsychic  field.  Word- 
blindness  (alexia),  or  the  loss  of  memory  of  printed  or  written  language, 
is  caused  by  a  lesion  here,  though  sight  itself  may  be  normal. 

Thus  the  basis  of  language  is  a  series  of  memory  pictures  (1)  of  the 
sound  of  words;  (2)  of  their  appearance;  (3)  of  the  effort  necessary  to 
enunciate  them,  and  (4)  to  write  their  symbols.  As  these  memory 
pictures  are  connected  with  each  other  and  with  others  that  make  up 
the  concept  by  subcortical  association  fibers  passing  between  them,  a 
lesion  in  any  of  these  association  tracts  also  leads  to  a  defect  of  speech. 
Those  who  have  lost  the  memory  picture  have  cortical  word-blindness 
or  deafness,  etc. ;  those  in  whom  it  cannot  be  recalled  by  ordinary  means, 
though  it  remains  intact,  have  subcortical  word-blindness,  etc. 

It  may  be  added  that  Marie  holds  that  aphasia  is  an  intellectual 
deficit  due  to  a  lesion  of  the  zone  of  Wernicke,  comprising  the  areas  given 
above  as  those  of  visual  and  auditory  speech.  Further,  that  aphasia  is  a 
unit  and  not  made  up  of  sensory  and  motor  aphasia,  and  that  in  motor 
aphasia  there  is  no  lesion  in  Broca's  convolution,  but  in  addition  to  a 
lesion  of  the  zone  of  Wernicke  an  involvement  of  the  region  of  the  len- 
ticular nucleus. 

The  primary  or  lower  visual  centre  is  in  the  occipital  lobe,  especially 
in  the  vicinity  of  the  cuneus  and  the  calcarine  fissure.  Owing  to  the 
decussation  of  fibers  in  the  optic  chiasm,  the  blindness  due  to  a  lesion  of 
this  cortical  centre  is  a  homonymous  hemianopsia  or  half-blindness  of 
both  eyes,  the  blind  visual  field  being  on  the  same  side  of  the  body  in 
both  eyes  and  on  the  side  opposite  the  lesion. 

The  higher  visual  or  visuopsychic  centre.  The  visual  memories  of 
things  seen  are  largely  located  in  the  left  lateral  occipital  cortex  in  right- 
handed  persons,  and  vice  versa.  Hence  psychic  blindness,  or  the  failure 
to  recognize  objects  seen,  may  be  due  to  an  extensive  lesion  of  the  left 
occipital  cortex  in  right-handed  persons,  or  to  a  lesion  of  both  sides. 

The  auditory  centre  is  in  the  middle  of  the  first  temporal  convolution 
and  the  adjacent  cortex.  But  as  each  centre  is  connected  with  both  ears, 
a  unilateral  lesion  fails  to  cause  deafness. 

The  auditory  memories  of  things  heard,  as  well  as  of  speech,  are  appar- 
ently stored  on  the  left  side  in  right-handed  persons,  and  vice  versa, 
Hence  psychic  deafness,  as  well  as  word  deafness,  is  due  to  a  lesion  of  the 
left  temporal  cortex. 

The  centre  for  the  sensation  of  smell  is  thought  to  be  in  the  uncinate 
gyrus,  on  the  under  surface  of  the  temporal  lobe  near  the  tip,  and  the 
centre  for  taste  is  probably  with  or  near  that  for  smell.  As  each  centre 
is  related  to  both  sides  of  these  sensory  organs,  only  bilateral  lesions 
would  produce  loss  of  these  senses. 

A  large  part  of  the  cortex  is  thus  seen  to  be  wanting  in  known  function. 
<  )f  this  portion  Flechsig  has  described  four  areas  in  the  adult,  not  present 
in  the  infant,  whose  structure  is  alike,  and  whose  time  of  development 


46  THE  HEAD  AND  NECK 

differs  from  that  of  other  parts.  These  areas  lie  in  the  frontal,  temporal, 
and  posterior  parts  of  the  parietal  lobe  and  in  the  insula,  and  are  called 
mental  or  association  centres  because  they  join  together  the  activities  of  the 
various  organs  of  sense.  These  and  other  unnamed  areas  of  the  cortex 
are  probably  related  to  the  higher  forms  of  intellectual  activity,  for  the 
full  play  of  which  a  general  integrity  of  the  whole  brain  is  necessary. 
But  a  disease  in  any  one  of  the  parts  does  not  cause  the  loss  of  any 
one  mental  faculty.  Thus  very  considerable  disease,  injury,  or  loss  of 
substance  has  involved  the  frontal  lobes  without  a  serious  disturbance  of 
the  mental  powers.  It  is  now  generally  thought,  however,  that  the  loca- 
tion of  the  seat  of  the  higher  psychical  functions  is  in  the  prefrontal 
region,  more  particularly  that  on  the  left  side. 

The  function  of  the  corpora  striata  and  optic  thalami  is  undetermined. 
Lesions  of  them  cause  no  definite  symptoms  unless  they  involve  the 
tracts  in  the  internal  capsule.  The  crura  cerebri,  pons,  and  medulla  contain 
the  centres  of  the  cranial  nerve  nuclei  and  transmit  the  motor  and  sensory 
tracts  to  the  cord.  Hence  lesions  in  them  cause  cranial  nerve  palsies  on 
the  same  side  and  motor  and  sensory  paralyses  of  the  opposite  extremi- 
ties. Lesions  of  the  crura  involve  especially  the  third  cranial  nerve, 
those  of  the  pons,  the  fifth,  sixth,  seventh,  and  eighth. 

Lesions  of  the  cerebellum,  if  confined  to  its  hemispheres,  may  cause  no 
symptoms,  but  if  in  the  median  or  vermiform  lobe  may  produce  two 
characteristic  symptoms,  a  staggering  gait  known  as  cerebellar  ataxia, 
and  vertigo. 

The  medulla  contains,  in  addition  to  the  centres  named  above,  many 
automatic  centres,  such  as  the  respiratory,  vasomotor,  and  heat-regulating 
centres  and  the  inhibitory  centre  of  the  heart,  also  the  reflex  centres  for 
deglutition,  sneezing  and  coughing,  etc. 

Upon  the  above  local  symptoms  we  are  dependent  for  our  diagnosis 
of  the  location  of  a  lesion.  In  order  to  be  able  to  expose  by  operation  that 
part  of  the  brain  where  the  lesion  is  thus  located  we  must  be  able  to 
locate  certain  of  the  fissures  of  the  brain  on  the  surface  of  the  head. 

Craniocerebral  Topography. — 1.  The  Relations  of  the  Brain  as  a  Whole 
to  the  Skull. — The  lower  limit  of  the  cerebrum  is  approximately  indicated 
by  a  line  slightly  convex  upward,  about  8  mm.  (^  in.)  above  the  supra- 
orbital margin,  crossing  the  temporal  crest  12  mm.  (■§•  in.)  above  the 
external  angular  process  of  the  frontal  bone,  thence  somewhat  convex 
downward  and  forward  to  about  the  centre  of  the  zygoma,  and  along  the 
upper  border  of  this  process  to  just  above — 6  mm.  (\  in.) — the  external 
auditory  meatus,  and  from  here  to  the  external  occipital  protuberance 
just  above  the  lateral  sinus  (see  p.  38).  Below  the  latter  part  of  the  line 
lies  the  cerebellum.  Each  cerebral  hemisphere  extends  up  to  the  superior 
longitudinal  sinus  (see  p.  36),  a  little  to  one  side  of  the  median  line. 

2.  As  to  the  fissures,  the  localization  of  the  fissures  of  Rolando  and 
Sylvius,  and  perhaps  also  of  the  parietooccipital  fissure,  enables  the  sur- 
geon to  expose  all  the  cortical  areas  whose  function  is  definitely  known. 

The  Fissure  of  Rolando. — Measure  in  the  median  line  the  distance 
between  the  root  of  the  nose  (nasion)  and  the  external  occipital  pro- 


THE  III:' AD 


47 


tuberance.  12  mm.  (+  in.)  (Thane)  to  25  mm.  (Kocher)  behind  the  centre 
of  this  line  (or  1(l'(l  of  the  distance  back  from  the  nasion)  represents 
the  superior  Rolandic  point,  or  the  point  where  the  continuation  of  this 
fissure  meets  the  median  line.  From  this  point  a  line  drawn  downward 
and  forward  at  an  angle  of  07  degrees  with  the  median  line  lies  over  the 
fissure  of  Rolando.  This  angle  is  simply  and  accurately  determined  by 
folding  a  sheet  of  paper  so  as  to  divide  the  right  angle  into  two  equal 
halves  and  repeating  the  process  with  one  of  the  angles  of  45  degrees. 
Turning  down  or  cutting  off  one  of  the  resulting  angles  of  22.5  degrees 


Fig.  10 
bregma  f.  of  rolando 


PAR.  OCCIP. 
FISSURE 
LAMBDA 


Craniocerebral  topography,  showing  relation  of   brain  ami  Rome  of   the  fissures  ami   convolutions 
in  the  tuture    anil  bony  landmarks.    X  indicates  position  of  parietal  eminence. 


leaves  an  angle  of  67.5  degrees.  This  fissure  is  about  8.5  cm.  (3$)  inches 
long  and  commences  12  nun.  (I  in.)  or  SO  from  (lie  median  line.  In  its 
lower  third  the  fissure  becomes  a  little  more  vertical  than  this  line.     The 

upper  end  of  the  (insure  of  Rolando  may  also  be  found  by  drawing  Reid's 
base  line,  from  the  infra-orbital  margin  through  the  centreof  the  external 

auditory  meatus,  and  erecting  a  perpendicular  from  the  posterior  border 
of  the  mastoid  process  (Reid,  Krdnlein).  Where  the  latter  line  reaches 
ili<-  median  line  gives  us  tin-  upper  Rolandic  point  from  which  to  draw 

tin-    line    as    before.       Of    it     may    be    drawn    from    this    point     lo    the 

inferior  Rolandic  point,  where  another  perpendicular  to  the  base  line, 


48 


THE  HEAD  AND  NECK 


just  in  front  of  the  external  auditory  meatus,  intersects  the  fissure  of 
Sylvius  (Reid).  This  intersection  lies  on  the  anterior  perpendicular  line 
about  5  cm.  (2  in.)  above  the  external  auditory  meatus.  According  to 
Le  Fort  the  direction  of  the  fissure  of  Rolando  is  also  represented  by  a 
line  connecting  the  uppermost  point  of  this  fissure,  as  determined  by 
either  of  the  preceding  methods,  with  the  middle  of  the  zygomatic  arch. 
The  lower  end  of  the  fissure  of  Rolando  is  about  12  mm.  (J  in.)  above  the 
fissure  of  Sylvius  and  2.5  cm.  (1  in.)  behind  the  junction  of  that  fissure 
with  its  vertical  limb,  or  about  7.5  cm.  (3  in.)  behind  the  external  angular 
process.    The  lower  end  of  the  fissure  of  Rolando  is  about  28  mm.  (1-Jin.), 


GLABELLA  X 


PAR.  OCCIP. 
FISSURE 


Craniocerebral  topography,  showing  the  relation  of  the  fissures  of  Rolando  and  Sylvius,  the  middle 
meningeal  artery,  and  the  lateral  sinus  to  the  landmarks  and  sutures  of  the  head. 


the  upper  end  5  cm.  (2  in.)  behind  the  coronal  suture.  The  upper  end  is 
about  at  the  centre  of  the  sagittal  suture,  or  nearly  5  cm.  (2  in.)  behind 
the  Bregma.  The  two  central  convolutions  take  up  about  2.5  cm.  (1  in.) 
on  each  side  of  the  fissure  of  Rolando.  In  the  adult,  the  highest  part  of 
the  temporal  ridge  crosses  the  Rolandic  fissure  at  about  the  junction  of 
its  middle  and  lower  thirds,  i.  e.,  between  the  motor  areas  for  the  arm  and 
face. 

The  Fissure  of  Sylvius. — The  main  stem  of  this  fissure  meets  the  lateral 
surface  of  the  skull  at  the  Sylvian  point,  which  is  where  the  fissure  divides 
into  its  three  branches  and  about  corresponds  to  the  pterion.    It  may  be 


THE  HEAD 


49 


located  on  the  surface  by  a  point  6  to  10  mm.  (J  to  J-  in.)  vertically  above 
the  end  of  a  line  drawn  horizontally  backward  for  3  cm.  (1£  in.)  from  the 
external  angular  process.  It  is  also  at  the  intersection  of  a  vertical  line 
from  the  middle  of  the  zygoma  with  a  line  drawn  through  the  supra- 
orbital margin  and  parallel  with  the  base  line  (Kronlein) .  The  fissure 
of  Sylvius  posterior  horizontal  limb)  is  represented  on  the  surface  by 
a  line  connecting  the  Sylvian  point  and  the  temporal  ridge  at  a  point 
IS  nun.  1 1  in.  |  below  the  most  prominent  point  of  the  parietal  eminence. 


Fig.  12 


J       / 


Projection  of  middle  meningeal  artery  on  the  lateral  surface  of  the  skull.  Kronlein's  method 
«.f  determining  the  position  of  the  middle  meningeal  artery  and  the  fissures  of  Rolando  and 
Sylvm-.  .1.  Sylvian  point;  O,  Rolsndic  point;  A  C,  anterior  vertical  line  drawn  through  the 
middle  of  the  zygoma;  l>  E,  middle  vertical  line  drawn  through  condyle  of  lower  jaw;  //  li  (>, 
oi  vertical  line  drawn  through  the  hack  of  the  base  of  the  mastoid  process  to  the  median 
■gittal  line  at  0;  .1  and  li,  the  points  to  trephine  for  the  anterior  and  posterior  branches  of 
the  middle  meningeal  artery  in  case  "f  hemorrhage  within.  Within  the  rectangle  below  /'-'  li 
Otitic  brain  absce.nses  in  the  temporal  lobe  are  to  be  opened.  The  fissure  of  Sylvius  bisects  the 
aii^le  between  the  upper  horizontal  line,  through  upper  border  of  orbit,  and  the  Rolandic  line  A  (>. 


It  may  be  more  accurately  represented  by  a  line  from  the  external 
angular  process  to  a  point  75  per  cent.  (Taylor  and  Haughton)  or 
80 per  cent.  (Chipault)  of  the  distance  from  the  nasion  to  the  inion, 
or  by  ;i  line  bisecting  (lie  single  formed  between  the  line  through 
the  upper  margin  of  tin-  orbit  and  parallel  with  theba.se  line,  and  the 

line  connecting    the  superior    Kolandie  and    Sylvian    points   (Kronlein) 

12).    The    Ik, it  ascending  limb  ascends  for  about  2.5  cm.  (I  in.) 

■'•hind  the  lower  end  of  the  eoronal  suture.    As  the  posterior  hori- 
1 


50 


THE  HEAD  AND  NECK 


zontal  limb  may  be  said  to  commence  at  this  point,  the  1.5  cm.  or  so 
of  the  Sylvian  line  in  front  of  this  represents  the  main  fissure.  The 
line  representing  the  fissure  of  Sylvius  is  about  8.5  cm.  (3^  in.)  long, 
its  anterior  part  is  just  above  (Horsley).,  below,  or  in  the  line  of  the 
squamous  suture.  Around  its  hind  end  lies  the  supramarginal  gyrus, 
to  which  the  parietal  eminence  fairly  accurately  corresponds.  Below 
the  Sylvian  fissure  lies  the  first  temporal  gyrus.  The  anterior  part 
of  the  fissure  slants  gently,  the  posterior  part  more  sharply  upward. 


Craniocerebral  topography;  45  per  cent,  of  median  naso-inionic  line,  pre-Rolandic  point; 
55  per  cent.,  Rolandic  point;  70  per  cent.,  Sylvian  line;  80  per  cent.,  lambda;  95  per  cent, 
gives  lower  edge  of  occipital  lobe;  line  from  A,  external  angular  process,  to  70  per  cent,  gives 
Sylvian  fissure;  S,  Sylvian  point,  junction  of  second  and  third  tenths  of  this  line;  R°,  inferior 
Rolandic  point,  junction  of  its  third  and  fourth  tenths. 

The  Parieto-occipital  Fissure. — The  parieto-occipital  fissure  lies  2  to  3 
mm.  (y2  to  j$  in.)  in  front  of  the  lambda  (Horsley)  or  where  the  line 
representing  the  fissure  of  Sylvius,  if  continued,  would  reach  the 
median  line  (or  a  little  below  this).  It  separates  the  parietal  and 
occipital  lobes,  and  its  external  limb  runs  outward  on  the  external 
surface  of  the  brain  for  about  2.5  cm.  (1  in.). 

It  may  be  added  that  the  coronal  suture  lies  over  the  posterior  extremi- 
ties of  the  three  frontal  gyri,  the  sulci  separating,  which  may  be  repre- 
sented as  follows :  the  superior  by  a  line  drawn  backward  from  the  supra- 
orbital notch  parallel  with  the  median  line,  the  inferior  by  the  frontal 
part  of  the  temporal  ridge.     The  lateral  ventricle  may  be  reached  by 


THE  HEAD 


51 


Fig.  14 

Superior  frontal  fissure. 


End  of  calloso 
marginal  fissure.\ 


Inferior  frontal 
lobe. 


tcdpital 
Mature. 


Fissure  of 
Sylvius. 


Drawing  to  illustrate  craniocerebral  topography.      (Macalister.)      Taken  from  a  cast 
prepared  by  Professor  Cunningham. 


Fig.  15 


tion  '>(  the  lateral  ventricles,  middle  car  and  lateral  Minus  on  the  .--i'lc;  <>f  the  head. 


52  THE  HEAD  AND  NECK 

penetrating  only  1  cm.  of  brain  tissue,  through  the  posterior  half  of  the 
first  temporal  convolution,  3.7  cm.  (1§  in.)  below  the  parietal  eminence; 
or  at  the  depth  of  4  to  5  cm.  through  the  superior  frontal  sulcus,  about 
5.5  cm.  (2|  in.)  in  front  of  the  Rolandie  fissure.  It  may  be  drained 
through  an  opening  3  cm.  (1J  in.)  behind  and  the  same  distance  above 
the  external  auditory  meatus  by  an  instrument  directed  toward  the  top 
of  the  opposite  auricle  and  penetrating  the  brain  for  5  cm.  (2  in.),  unless 
the  ventricle  is  distended. 

It  should  be  remembered  that  the  sulci  and  gyri  are  never  precisely 
alike  and  that  their  relations  to  the  surface  vary  slightly  in  different 
individuals,  but  as  we  expose  a  considerable  area  in  most  cases,  the 
desired  area  is  sure  to  be  exposed  and  can  be  recognized  by  its  relation 
to  the  sulci  and,  in  the  motor  area,  by  electrical  stimulation. 


THE  EAR. 

The  Pinna,  Auricle,  or  External  Ear. — The  pinna,  auricle,  or  external 
ear  is  formed  by  a  partial  fusion  of  six  small  tubercles  on  the  skin  at  the 
end  of  the  first  visceral  cleft.  In  connection  with  this  cleft  are  developed 
the  Eustachian  tube,  tympanum,  and  external  meatus.  A  supplemental 
rudimentary  pinna  is  sometimes  formed  at  the  margins  of  one  of  the  lower 
clefts,  appearing  congenitally  as  an  irregular  mass  of  fibrocartilage  on  the 
side  of  the  neck.  When  the  fusion  of  the  six  tubercles  is  less  complete 
than  usual,  a  tag-like  supernumerary  auricle  may  be  present  on  the 
cheek  just  in  front  of  the  ear,  or  fistulce  or  fissures  of  the  auricle  may 
occur.  The  more  marked  congenital  fistulse  may  be  due  to  defective 
closure  of  the  first  visceral  cleft.  A  dermoid  cyst  of  the  pinna  may 
result  if  the  opening  of  such  a  fistula  closes. 

The  framework  of  yellow  elastic  cartilage  gives  the  ear  its  essential 
shape,  which  varies  greatly  in  individuals  and  is  largely  influenced  by 
heredity.  A  hematoma  may  occur  between  the  skin  and  the  cartilage  of 
the  ear,  and  is  most  common  among  athletes,  such  as  football  players, 
boxers,  or  prize  fighters,  and  among  the  insane.  The  resulting  deposit 
and  contraction  of  new  connective  tissue,  especially  when  the  accident 
recurs,  as  in  the  left  ear  of  prize  fighters,  causes  the  markings  of  the  ear 
to  become  obliterated  and  replaced  by  a  wrinkled  flattened  surface,  a 
condition  sometimes  known  as  prize  fighter's  ear.  Curiously  enough,  a 
fine  antique  bronze  statue  of  a  boxer  discovered  in  Rome  in  1885,  and 
some  other  antique  statues,  show  this  same  condition  of  the  left  ear. 

The  auricle  is  so  firmly  attached  to  the  skull  by  the  cartilaginous 
meatus  that  a  body  of  average  weight  may  be  lifted  from  the  ground  by 
the  ears.  The  removal  of  the  pinna  is  followed,  as  a  rule,  by  compara- 
tively little  diminution  of  hearing.  As  there  is  but  little  subcutaneous 
fatty  tissue  between  the  skin  and  the  cartilage  the  bloodvessels  of  the  ear 
are  not  well  protected  against  cold,  so  that  the  ear  is  often  frostbitten. 
As  the  trunk  of  the  posterior  auricular  artery  occupies  the  angle  between 
the  auricle  and  the  mastoid  process,  we  carry  the  incision  to  expose  the 


THE  EAR 


53 


antrum  or  mastoid  process  a  little  behind  this  angle.  In  infants  this 
incision  should  not  be  carried  too  far  downward  and  forward,  for,  owing 
to  the  very  small  size  of  the  mastoid,  the  exit  of  the  facial  nerve  from  the 
canal  is  unprotected  and  upon  the  lateral  rather  than  upon  the  basal 
surface  of  the  skull. 

The  External  Auditory  Canal. — The  external  auditory  canal  in  the  adult 
is  about  3  cm.  (\\  in.)  in  length,  of  which  one-third  belongs  to  the  car- 
tilaginous and  two-thirds  to  the  bony  portion.  In  the  infant  the  bony 
part  is  a  mere  ring  and  the  canal  is  cartilaginous  and  nearly  straight, 
which  renders  an  examination  easier.     However,  in  the  examination  of 

Fig.  16 


FENESTRA    OVALtS 
LOSED    BY  STAPES 


Vertical  section  through  the  external  auditory  meatus  and  tympanum,  passing  in  front  of 
the  fenestra  ovalis.      (Gerrish,  after  Testut.) 


infant-,  the  auricle  should  be  drawn  downward  and  backward  to  draw 
away  the  floor  of  the  canal  from  the  drum  membrane,  with  which  it  is 
in  contact,  owing  to  the  obliquity  of  the  latter.  Owing  to  the  obliquity 
of  the  (hum  membrane  the  inferior  and  anterior  walls  are  longer  than 
the  superior  and  posterior  respectively. 

Its  general  direction  is  inward,  forward,  and  somewhat  downward,  but 
in  passing  from  without  inward  ihe  outer  portion  slopes  upward,  the 
inner  part  downward  so  that  the  centre  of  the  canal  is  the  highest  point 
of  an  upward  convexity.    Furthermore,  the  outer  part  inclines  sharply 

forward  and  then  bends  backward,  while  the  bony  or  inner  portion 
inclines  gently  forward  again.      I  leiicc  in  the  adult,  to  straighten  the  canal 

to  introduce  a  speculum  and  be  able  to  sec  {he  entire  membrane, 


54  THE  HEAD  AND  NECK 

the  pinna  is  pulled  upward  to  straighten  the  upward  curve  and  back- 
ward to  straighten  the  anteroposterior  curves.  The  external  meatus, 
the  promontory,  the  cochlea,  and  the  internal  meatus  lie  nearly  in  the 
same  line. 

Diameters. — The  outer  end  is  elongated  vertically,  the  inner  end 
slightly  transversely,  while  the  middle  part  is  circular.  On  these  differ- 
ences depend  the  two  forms  of  ear  specula,  the  one  round,  which  fits  the 
narrow  circular  median  part  of  the  canal,  the  other  oval,  which  fits  and 
fills  the  outer  part  of  the  canal.  The  latter  admits  more  light  at  the  outer 
end,  the  former  has  a  larger  lumen  where  it  reaches  the  bony  portion. 
The  osseous  part  is  narrower  than  the  cartilaginous,  and  the  narrowest 
part  of  the  canal  is  at  the  junction  of  the  middle  and  inner  thirds. 

The  cartilaginous  portion  of  the  canal  has  a  partial  framework  of  elastic 
fibrocartilage,  continuous  with  the  pinna.  This  cartilage  forms  but  two- 
thirds  of  the  circumference,  is  incomplete  above  and  behind,  and  tails  off 
as  it  passes  inward  to  become  attached  to  the  lower  third  only  of  the 
margin  of  the  osseous  meatus.  This  attachment  is  by  dense  fibro-elastic 
tissue,  which  allows  of  the  shifting  of  position  of  the  pinna  on  traction. 
The  cartilage  presents  clefts  or  fissures  (fissures  of  Santorini)  on  the 
floor  of  the  meatus,  which  are  filled  with  fibrous  tissue.  They  permit 
of  easier  movement  of  the  cartilaginous  portion  and  allow  the  spread  of 
inflammation  or  of  an  abscess  from  the  parotid  gland  below  into  the 
auditory  canal,  or  vice  versa. 

The  skin  lining  the  outer  part  of  the  cartilaginous  portion  is  supplied 
with  numerous  hairs,  which  help  to  keep  out  dust  and  insects,  and  with 
sebaceous  and  ceruminous  glands.  The  former  glands  are  often  the  seat  of 
furuncles  which  are  small  but  very  painful,  owing  to  the  firmness  of  the 
tissues,  due  to  the  close  attachment  of  the  skin  to  the  cartilage  and  peri- 
osteum. The  "  wax"  secreted  by  the  ceruminous  or  wax  glands  is  thought 
to  be  a  defence  against  dust  and  the  intrusion  of  insects.  When  this  wax 
is  secreted  excessively  it  may  produce  plugs,  which  cover  the  drum  mem- 
brane or  block  the  meatus,  interfering  with  air  conduction  and  so  produce 
deafness,  which,  curiously  enough,  usually  comes  on  suddenly  and  is  con- 
tinuous. The  skin  lining  the  osseous  portion  is  thinner  and  only  contains 
glands  along  its  posterosuperior  part.  The  skin  of  the  meatus  is  liable  to 
eczema  and  may  become  inflamed  (otitis  externa),  giving  rise  to  a  profuse 
mucopurulent  discharge.  In  addition  to  small  furuncles,  a  less  common 
but  more  serious  and  more  diffuse  form  of  infection  may  occur  beneath 
the  periosteum.  This  may  spread  out  onto  the  surface  of  the  mastoid, 
beneath  the  periosteum,  or  it  may  extend  downward  into  the  parotid 
region,  through  the  fissures  of  the  cartilage  or  a  gap  in  the  floor  of  the 
osseous  portion.  This  gap  is  explained  as  follows.  The  osseous  portion 
is  largely  formed  by  the  outward  growth  of  the  tympanic  ring,  at  first  in 
two  lateral  tubercles  which  meet  in  the  floor,  leaving  an  opening  mesial 
to  their  junction,  which  may  sometimes  persist.  Polypi  may  grow  from 
the  soft  linings  of  the  canal  and  exostoses  from  its  bony  walls. 

Foreign  bodies  are  often  lodged  in  the  meatus,  particularly  at  its  inner 
third.    They  may  be  very  difficult  of  extraction.    More  damage  has  been 


THE  EAR  55 

clone  in  many  cases  by  blind  or  forcible  attempts  to  remove  the  foreign 
body  than  by  leaving  it  in  place.  The  ear  drum  and  tympanum  have 
been  injured  in  such  attempts  at  removal,  while,  on  the  other  hand,  cases 
are  reported  where  foreign  bodies  have  remained  in  the  ear  from  thirty 
to  sixty  years  without  harm.  The  extraction  should  only  be  attempted 
by  means  of  appropriate  forceps  or  a  blunt  hook,  while  the  body  is  seen 
and  the  instruments  guided  to  it  through  a  speculum;  or  by  means  of  a 
stream  of  tepid  water  forcibly  injected  through  the  narrow  nozzle  of 
a  svringe,  so  as  to  get  behind  the  bodv  and  force  it  out. 

Relations  of  External  Auditory  Canal. — The  relations  of  the  external 
auditory  canal,  especially  its  bony  portion,  are  of  practical  importance. 
The  superior  wall  is  in  relation  with  the  middle  fossa  of  the  skull  and  is 
separated  from  it  by  a  bony  plate  4  to  5  mm.  (A  in.)  thick,  and  sometimes 
thinner.  Hence  long-continued  subperiosteal  inflammation  or  bone 
disease  in  the  canal  may  extend  to  the  meninges  or  the  brain,  without 
necessarily  first  involving  the  tympanum.  Posteriorly  the  canal  is  in 
relation  with  the  mastoid  process  and,  at  its  inner  end,  with  the  mastoid 
antrum.  From  the  latter  the  canal  is  separated  by  a  thin  plate  of  bone, 
sometimes  defective,  so  that  inflammations  of  the  one  may  extend  to  the 
other  and  inflammation  in  the  antrum  may  often  cause  a  swelling  or 
bulging  of  the  posterosuperior  aspect  of  the  inner  end  of  the  canal.  The 
inferior  wall  is  in  relation  with  the  portion  of  the  parotid  gland  occupying 
the  back  of  the  glenoid  fossa  and,  as  stated  above,  a  congenital  gap  may 
occur  here  which  permits  the  ready  extension  of  inflammation  from  the 
one  to  the  other.  The  anterior  wall  is  in  relation  to  the  temporomaxillary 
joint,  and  may  be  fractured  by  the  condyle  of  the  jaw  in  falls  upon  the 
chin.  As  a  result  of  this  injury  there  may  be  considerable  bleeding  from 
the  ear,  as  also  in  case  the  drum  membrane  is  ruptured,  hence  this  symp- 
tom does  not  necessarily  indicate  fracture  of  the  base  of  the  skull.  The 
proximity  of  this  part  to  the  joint  helps  to  explain  the  pain  of  movement 
of  the  jaw  when  the  canal  is  inflamed.  This  is  also  explained  by  the  two 
parts  being  supplied  by  the  same  nerve  (auriculotemporal).  The  relation 
of  the  cartilaginous  portion  to  the  joint  is  appreciated  in  placing  the  finger 
in  the  ear  when  one  can  feel  the  movements  of  the  joint.  Just  behind  the 
upper  end  of  the  osseous  meatus  is  a  bony  prominence,  the  suprameatal 
spine.  This  important  landmark  is  about  10  to  12  mm.  (£  in.)  above  the 
floor  of  the  antrum  and  usually  about  1  cm.  in  front  of  the  bend  of  the 
sigmoid  sinus. 

Nerve  Supply. — The  auriculotemporal  supplies  parts  of  the  canal  and  the 
outer  surface  of  the  pinna.  The  great  auricular  and  small  occipital  nerves 
also  supply  the  pinna,  while  Arnold's  nerve  supplies  the  back  of  the  concha 
and  the  lower  and  back  part  of  the  outer  portion  of  the  canal.  Arnold's 
nerve,  a  small  branch  of  the  vagus,  has  been  nicknamed  ''alderman's 
nerve,"  from  the  following  circumstance.  It  is  said  that  diners  after  a 
heavy  dinner  were  wont  to  foneli  the  back  of  the  ear  with  a  napkin 
moistened  with  rose  water.    This  is  said  to  be  very  refreshing  by  reason 

of  the  Stimulation  of  Arnold's  nerve  and  thereby,  reflexlv,  of  the  main 

branch  of  the  vagus,  which  supplies  the  stomach. 


56  THE  HEAD  AND  NECK 

The  irritation  of  the  canal  by  a  plug  of  wax,  the  introduction  of  a 
speculum,  the  presence  of  a  foreign  body  or  of  an  inflammation  may  give 
rise  to  symptoms  which  are  explained  as  reflexes.  Thus  ear-coughing 
is  a  reflex,  through  Arnold's  nerve,  of  the  branches  of  the  vagus 
supplying  the  lungs.  Vomiting  has  been  caused  in  like  manner  by 
an  irritation  through  Arnold's  nerve  of  the  gastric  branches  of  the 
vagus.  In  ear-yawning  the  irritation  is  conveyed  through  the  auriculo- 
temporal nerve  to  other  branches  of  the  fifth  nerve  which  supply  the 
muscles  of  the  jaw.  Again,  other  branches  of  the  same  division  of  the 
fifth  nerve  supply  the  lower  teeth  (inferior  dental)  and  the  tongue  (gus- 
tatory), a  circumstance  that  may  account  for  the  frequent  association  of 
earache  with  toothache  or  disease  in  the  anterior  two-thirds  of  the  tongue. 

The  Tympanic  Membrane. — The  tympanic  membrane  is  placed  so  as 
to  face  obliquely  outward,  downward,  and  slightly  forward.  The  obliquity 
with  the  horizontal  plane  is  30  degrees  to  50  degrees  at  birth  and  40 
degrees  to  45  degrees  in  the  adult.  According  to  Fick,  the  more  vertical 
the  membrane  the  more  sensitive  is  it  to  sound,  and  it  has  been  observed 
to  be  less  oblique  in  musicians  than  in  those  lacking  in  a  taste  for  music. 
Owing  to  the  inclination  of  the  membrane  and  the  sloping  downward  of 
the  inner  end  of  the  canal  an  acute-angled  sinus  is  formed  between  the 
two,  where  small  foreign  bodies,  pus,  and  other  fluids  are  likely  to  collect. 
The  membrane  is  nearly  circular  but  slightly  longer  vertically  (10  mm.) 
than  horizontally  (9  mm.).  Its  shape,  however,  is  somewhat  irregular,  for 
above  and  anteriorly,  where  the  tympanic  ring  is  interrupted  by  a  slight 
recess,  the  notch  of  Rivini,  the  membrane  extends  to  the  margin  of  the 
tympanum.  This  portion  of  the  membrane,  limited  below  by  two  small 
fibrous  bands  connecting  the  two  angles  or  corners  of  the  notch  of  Rivini 
with  the  short  process  of  the  malleus,  bulges  outward  instead  of  inward, 
and  is  thin  and  lax,  hence,  called  by  Shrapnell  membrana  flaccida,  and  is 
known  as  Shrapnell' s  membrane.  This  from  its  thinness  may  be  readily 
ruptured  by  a  blow,  and  through  it  pus  may  escape  from  the  middle  ear 
without  perforation  of  the  membrane  proper. 

The  inward  bulging  of  the  tympanic  membrane  is  due  to  the  position 
of  the  long  process  or  handle  of  the  malleus,  which  is  embedded  between 
the  circular  and  radiating  fibers  of  the  membrane.  The  centre  or  umbo 
of  this  depression  is  slightly  below  the  centre  of  the  membrane  and,  as 
may  be  seen  from  either  side,  corresponds  to  the  slightly  flattened  end  of 
the  handle  of  the  malleus.  A  section  of  the  membrane  below  the  umbo 
shows  this  part  to  be  slightly  convex  externally.  When  pathological 
products,  such  as  mucus,  pus,  etc.,  are  pent  up  in  the  tympanum,  the 
inward  bulging  is  diminished  or  even  replaced  by  an  outward  one.  On 
the  other  hand,  when  the  Eustachian  tube  is  occluded  and  no  air  can 
reach  the  tympanum,  the  atmospheric  pressure  on  the  outside  of  the 
membrane  increases  the  inward  bulging  to  such  an  extent  that  the  stapes 
is  constantly  pressed  inward  and  a  ringing  in  the  ear  is  produced. 

The  otoscopic  image  (Fig.  17)  of  the  membrane  as  seen  through  an  ear 
speculum  is  that  of  a  round  or  oval,  concave  surface,  pearl-gray  in  color, 
with  sometimes  a  violet  or  yellowish-brown  tinge  and  with  the  following 
markings:   Extending  from  a  little  in  front  of  the  upper  pole  downward 


THE  EAR  57 

and  a  little  backward  to  the  umbo  is  seen  the  handle  of  the  malleus. 
In  front  of  the  upper  end  of  this,  and  near  the  circumference  of  the  mem- 
brane, is  a  whitish  point,  the  short  process  of  the  malleus.  Behind  and 
parallel  with  the  handle  of  the  malleus,  but  less  distinct  and  not  as  long, 
is  seen  the  long  process  of  the  incus.  Extending  downward  and  forward 
from  the  umbo  is  the  "  light  cone"  a  whitish  cone-shaped  area  of  varying 
shape  and  size  where  the  light  thrown  in  is  reflected  back,  owing  to  the 
inclination  and  curvature  of  the  membrane.  Pathologically  this  light 
cone  may  be  wanting  when  a  perforation  occupies  its  position,  when  it  is 
bulged  outward  or  the  surface  dulled  by  an  inflammation  of  the  mem- 
brane. Sometimes  the  chorda  tympani  nerve  may  be  seen  crossing  trans- 
versely near  the  upper  end  of  the  handle  of  the  malleus.  The  promontory 
may  also  be  seen  behind  the  umbo. 

Fig.  17 

POS.    FOLD 
OF    MEM- 
LONG    PROCESS    0^    INC,US|      BRANE        |SHORT    PROCESS 

OF    MALLEUS 

SHRAPNELL'S    MEMBRANE 
ANT.     FOLD    OF    MEMBRANE 


PROMONTORY- 


LIGHT    CONE 


Otoscopic  image  of  right  ear  drum.      (Testut.) 

Practically  we  may  divide  the  membrane  into  the  parts  above  and 
below  the  umbo.  The  section  above  the  umbo  corresponds  to  the  ossicles, 
their  muscles  and  ligaments,  the  chorda  tympani,  the  foramen  ovale,  and 
the  promontory.  The  greatest  vascularity  is  in  this  part,  the  bloodvessels 
being  especially  prominent  on  each  side  of  the  handle  of  the  malleus. 
The  section  of  the  membrane  below  the  umbo  corresponds  to  no  important 
parts  and  is  less  vascular  and  less  sensitive  than  the  upper  segment; 
hence  paracentesis  is  usually  practised  here  and  for  the  additional 
reason  that  the  lower  incision  affords  the  better  drainage  of  the  tympanum. 
It  is  noticeable,  however,  that  the  floor  of  the  tympanum  is  at  a  lower 
level  than  (lie  lower  end  of  the  membrane,  so  that  perfect  drainage  cannot 
cured  in  the  upright  position.  As  the  membrane  consists  of  a  frame- 
work of  circular  mid  radiating  fibers  of  connective  tissue,  covered  inter- 
nally by  mucous  membrane  and  externally  by  epidermis,  it  possesses 
little  elasticity;  henee  incisions  do  not  gape  much  and  heal  readily,  often 
before  it  i  desired,  so  that  paracentesis  may  need  to  be  repeated.  Tn 
.t  spontaneous  perforation  from  ulceration,  the  wider  opening  result- 
ing may  heal  slowly  and  sometimes  not  at  all.  Hut  an  opening  in  the 
in*-: nl  pane  does  not  necessarily  produce  much  deafness. 


58 


THE  HEAD  AND  NECK 


The  arteries  supplying  the  membrane  are  derived  from  the  stylo- 
mastoid artery  and  the  tympanic  branch  of  the  internal  maxillary,  the 
latter  supplying  mostly  the  part  below  the  umbo,  the  former  that  above 
it.     The  auriculotemporal  nerve  supplies  the  membrane. 

The  Tympanum  or  Middle  Ear.— The  tympanum  or  middle  ear  is  a 
narrow  cleft-like  cavity  intervening  between  the  external  auditory  canal 
and  the  internal  ear.  It  is  separated  from  the  former  by  the  ear  drum, 
the  vibrations  of  which  are  transmitted  to  the  internal  ear  by  a  chain  of 


Fig.  18 


Projection  of  the  middle  ear:  A,  Eustachian  tube;  B,  antrum;  C,  mastoid  cells;  D,  facial 
nerve;  E,  lateral  sinus;  F,  Gasserian  ganglion;  G,  internal  carotid  artery,  on  the  lateral  surface 
of  skull. 

three  ossicles  which  cross  this  narrow  space.  It  contains  air  which  reaches 
it  from  the  pharynx  through  the  Eustachian  tube,  and  it  connects 
posteriorly  with  the  mastoid  antrum  and  cells.  Its  mucosa  is  ciliated 
except  where  it  covers  the  membrane,  the  ossicles,  and  the  promontory, 
where  it  is  thin  and  squamous.  It  measures  15  mm.  (f  in.)  in  height 
and  length,  above  it  is  5  to  6  mm.  broad,  below  4  mm.,  and  the  umbo 
and  promontory  are  only  separated  by  1  to  2  mm.  It  projects  above 
the  upper  limit  of  the  membrane,  where  it  widens  out  somewhat  and 
is  called  the  tympanic  attic.  The  cavity  lies  obliquely  so  that  its  outer 
and  inner  walls  look  outward,  downward,  and  forward. 


THE  EAR 


59 


On  its  inner  wall,  opposite  the  umbo,  is  the  'promontory,  above  this  the 
fenestra  oralis  and  below  and  behind  the  latter  the  fenestra  rotunda.  The 
fenestra  ovalis  leads  into  the  vestibule  and  is  closed  during  life  by  the 
stapes.  In  the  angle  between  the  roof  and  the  inner  wall,  and  appearing 
as  a  slight  convexity  above  the  fenestra  ovalis,  is  the  facial  canal  (aque- 
ductus  Fallopii)  transmitting  the  facial  nerve.  The  wall  of  this  canal  is 
very  thin,  especially  in  infants  in  whom  it  may  be  defective.  This  fact 
accounts  for  facial  paralysis  in  the  course  of  chronic  otitis  media,  par- 
ticularly in  children. 


Fig.  19 


Projection  of  the  middle  ear:  A,  Eustachian  tube;  B,  antrum;  C,  mastoid  cells;  D,  facial  nerve; 
E,  lateral  sinus;  F,  Gasserian  ganglion,  on  the  base  of  the  skull. 

The  floor  of  the  tympanum  is  like  a  narrow  gutter  below  the  level  of 
the  ear  dm m,  and  hence  drainage  of  the  tympanum  is  not  perfect  after 
paracentesis  of  this  membrane.  The  floor  is  only  separated  from  the 
jugular  and  carotid  fossa  by  a  thin  plate  of  bone,  and  fatal  hemorrhage 
from  the  carotid  has  followed  necrosis  of  this  bony  plate. 

The  outer  wall  consists  chiefly  of  the  membrane,  but  is  partly  osseous 
and  presents  the  apertures  of  entrance  and  exit  of  the  chorda  tympani 
nerve,  which  lies  beneath  tin-  mucous  membrane  of  this  wall.  This  nerve 
the  upper  part  of  the  membrane  internal  to  the  handle  of  the 
malleus.  It'  affected  in  connection  with  otitis  media,  its  irritation  causes 
prickling  of  the  » 1 1«  I  of  the  tongue;  its  destruction,  unilateral  loss  of  taste 
in  the  anterior  two-thirds  of  the  tongue. 

The  roof  or  tegmen  tympani  's  ;|  V(,|'.v  thin  layer  of  bone  which  separates 
mpanum  from  tli<-  middle  fossa  of  the  skull  and  the  temporosphe- 


60  THE  HEAD  AND  NECK 

noidal  lobe.  Defects  are  sometimes  found  in  the  tegmen,  so  that  in  cases 
of  otitis  media  inflammation  may  spread  from  the  ear  to  the  meninges  or 
the  brain  by  direct  extension  through  such  defects  or  after  necrosis  of 
the  thin  bony  plate,  or  indirectly  along  small  veins  passing  through  the 
tegmen  to  the  sigmoid  and  superior  petrosal  sinuses.  In  most  otitic 
brain  abscesses  the  bone  is  diseased  directly  to  the  dura. 

The  petrosquamous  suture  forms  the  outer  boundary  of  the  tegmen,  the 
eminentia  arcuata  over  the  superior  semicircular  canal  and  the  groove 
leading  to  the  hiatus  Fallopii  form  the  inner  boundary.  The  suture' is 
generally  obliterated  by  the  end  of  the  twelfth  year,  before  which  time 
inflammation  may  readily  spread  through  the  suture  membrane  from  the 
tympanum  to  the  meninges.  The  suture  not  infrequently  remains  open 
longer.  Fracture  of  the  tegmen  and  rupture  of  its  closely  adhering  mem- 
branes causes  an  escape  of  cerebrospinal  fluid  into  the  middle  ear.  The 
tegmen  is  continuous  with  the  roof  of  the  antrum  behind,  and  slopes 
downward  in  front  to  become  continuous  with  the  roof  of  the  Eustachian 
canal. 

The  posterior  wall  at  its  upper  end,  on  a  level  with  the  tympanic  attic, 
presents  the  irregularly  triangular  opening  into  the  antrum,  and  below 
this  there  are  sometimes  smaller  openings  directly  into  the  mastoid  cells. 

As  the  result  of  chronic  inflammatory  changes  the  joints  of  the  ossicles 
may  become  stiffened,  so  that  they  do  not  readily  transmit  slight  vibra- 
tions. It  is  in  such  cases  of  partial  deafness  that  the  hearing  is  better  in 
a  noisy  place,  like  a  crowded  street  or  a  railway  train,  for  the  resulting 
vibrations  are  sufficient  to  set  the  ossicles  in  vibration  and  the  addi- 
tional vibrations,  due  to  the  voice,  are  more  readily  transmitted  to  the 
internal  ear.  When  the  malleus  and  incus  are  removed  and  the  membrane 
is  freely  perforated,  a  considerable  degree  of  hearing  may  be  retained,  the 
vibrations  being  transmitted  directly  to  the  stapes  through  the  aperture 
in  the  membrane.  The  tympanum  communicates  with  surrounding 
parts  by  many  apertures,  both  large  and  small,  through  which  patho- 
logical processes  may  extend  in  various  directions. 

The  Mastoid  Antrum. — The  mastoid  antrum,  variable  in  size,  but  about 
as  large  as  a  pea,  lies  behind  the  attic  of  the  tympanum  into  which  it 
opens.  The  passageway  is  frequently  on  a  higher  level  than  the  floor  of 
the  antrum,  so  that  drainage  into  the  tympanum  from  the  antrum  is  not 
well  provided  for,  and  fluid  is  apt  to  gravitate  into  the  mastoid  cells  which 
communicate  with  it.  As  the  facial  canal  descends  on  the  inner  wall  of 
this  passageway,  one  must  keep  to  the  outer  wall  of  the  passage  in  opera- 
tions, in  order  to  avoid  the  nerve.  It  follows  also  that  the  antrum  lies 
behind  the  facial  nerve. 

The  antrum  lies  nearer  the  outer  surface  of  the  skull  than  the  tym- 
panum, and  is  covered  externally  by  the  descending  plate  of  the  squamous 
bone,  between  the  temporal  ridge  and  the  squamomastoid  suture.  This 
plate  may  present  defects  at  birth,  exposing  the  antrum.  The  squamo- 
mastoid suture,  which  is  wide  in  infancy,  persists  frequently  until  puberty, 
occasionally  through  life,  and  traces  of  it  are  also  found  in  the  adult  in 
the  shape  of  foramina,  through  some  of  which  minute  veins  pass  out 


THE  EAR  61 

from  the  antrum  and  tympanum.  Inflammation  travelling  along  these 
veins  may  set  up  a  periostitis  on  the  mastoid.  So  long  as  this  suture 
remains  unossified  inflammation  may  spread  and  pus  find  a  free  outlet 
to  the  surface  from  the  tympanum  antrum,  an  occurrence  not  infrequent 
in  children. 

Operations  confined  to  this  plate  of  the  squamosal,  i.  e.,  above  the 
squamomastoid  suture,  are  safe  as  regards  injury  to  the  sigmoid  sinus  or 
the  facial  canal.  Roughly  speaking,  the  level  of  the  antrum  corresponds 
to  that  of  the  upper  half  of  the  external  osseous  meatus,  and  the  passage 
between  the  tympanum  and  the  antrum  corresponds  to  the  postero- 
Miperior  quadrant  of  the  meatus.  Hence  the  operation  of  opening  the 
antrum  is  commenced  in  the  bone  just  behind  this  quadrant,  where 
Macewen  has  pointed  out  the  existence  of  what  he  calls  the  suprameatal 
triangle.  This  occurs  in  99.5  per  cent,  and  is  well-marked  in  94.6  per 
cent,  of  cases.  It  is  usually  a  depressed  area,  sometimes  a  slightly  promi- 
nent one.  It  is  bounded  above  by  the  posterior  root  of  the  zygoma,  below 
by  the  posterosuperior  quadrant  of  the  external  meatus,  and  behind 
by  a  vertical  line  drawn  tangent  to  the  posterior  border  of  the  meatus. 
The  opening  is  to  be  made  at  the  latter  line,  the  base  of  the  triangle,  and 
is  to  be  carried  inward,  with  a  slight  inclination  forward,  parallel  with  the 
bony  external  auditory  canal,  the  direction  of  which  may  be  determined 
by  a  probe  passed  into  it  posteriorly  between  the  skin  and  the  bony  wall. 
At  this  point  of  entrance  the  outer  wall  of  the  antrum  is  about  2  mm.  thick 
in  the  infant,  1  cm.  at  nine  years  (Symington),  and  \\  cm.  (f  in.)  or  less 
in  the  adult,  while  the  inner  wall  averages  18  mm.  (f  in.)  from  the  surface 
in  the  adult.  The  opening  to  reach  the  antrum  should  not  be  carried 
deeper  than  this  for  fear  of  injuring  the  facial  nerve.  Hence  in  infants 
pus  in  the  antrum  can  readily  reach  the  surface  or  be  readily  evacuated 
by  operation.  As  the  increase  of  growth  of  the  mastoid  involves  prin- 
cipallv  the  outer  part,  the  antrum  becomes  more  and  more  deeply  placed. 

The  other  relations  of  the  antrum  are  of  great  importance  in  case  of 
inflammation  extending  into  this  cavity  or  of  operations  to  evacuate  the 
pus.  Such  inflammations  readily  extend  into  the  antrum  from  the 
tympanum  on  account  of  the  free  opening  between  them  and  the  con- 
tinuity of  their  lining  mucosa?.  The  mucosa  of  the  antrum  is  thin  and 
not  ciliated.  The  roof  or  tegmen  antri  is  a  very  thin  plate  (about  1  nun. ) 
of  bone  continuous  with  but  at  a  little  higher  level  than  the  tegmen 
tympani.  Inflammation  may  readily  extend  through  this  thin  roof  to 
tin-  meninges,  causing  meningitis,  or  info  the  neighboring  brain,  causing 
an  abscess  of  the  temporosphenoidal  lobe  or  of  the  cerebellum.  The 
lower  border  of  the  posterior  root  of  the  zygoma  indicates  the  level  of  the 
roof  <,f  the  antrum,  or  it  may  lie  ;i  little  above  it.  A  few  millimeters  above 
this  i>  th<-  base  of  the  brain.  That  pari  of  the  anterior  antral  wall  sepa- 
rating the  antrum  from  the  inner  end  of  the  external  auditory  canal  is  thin 
and  sometimes  defective  (see  p.  55).  Postero-internally  the  antrum  is  in 
close  relation  with  the  sigmoid  sinus,  ~>  to  7  mm.  i  ',  to  ',  in.),  intervening 
in  the  infant.   The  rear  of  the  antrum  may  be  f reerj  and  safely  exposed  as 

far  BS  it-  outer  covering  by  the  descending  plate  of  the  squamous  extends 


62 


AQUEDUCT   OF    FALLOPIUS 

Coronal  section  of  the  right  temporal  bone,  passing  through  the  Eustachian  tube  and  the  middle 
of  the  tympanum.  Both  surfaces  of  the  section  are  shown,  the  parts  being  hinged  on  the  line  xx. 
(Gerrish,  after  Testut.) 


Fig.  21 


Mastoid  process  of  an  adult  opened  to  expose  and  show  the  relations  of  the  antrum,  facial  nerve, 
sigmoid  sinus,  etc.:  Du,  dura  of  middle  fossa;  A,  antrum;  Si,  sinus;  V.F,  mastoid  emissary 
vein;  C,  mastoid  cells;  F,  facial  nerve;  Flt  fenestra  ovalis;  Pr,  promontory;  St,  stapes;  B, 
horizontal  semicircular  canal. 


THE  EAR  63 

Development. — The  antrum  is  present  and  nearly  of  full  size  at  birth, 
while  the  mastoid  cells  are  developed  later.  The  mastoid  process  is 
present  at  birth,  but  does  not  become  pronounced  externally  until  about 
the  second  year,  and  it  continues  to  grow  for  many  years.  The  mastoid 
cells  are  developed  with  the  process,  but  at  first  are  like  spaces  of  cancellous 
bone;  the  true  air  cells  do  not  appear  until  after  puberty.  The  cells  of 
the  mastoid  continue  to  enlarge  and  extend  well  into  adult  life,  when  they 
mav  reach  superiorly  within  12  mm.  (£  in.)  of  the  squamoparietal  suture, 
anteriorly  over  the  external  meatus,  posteriorly  to  the  mastooccipital 
suture,  and  rarely  beyond  it. 

The  antrum  is  surrounded  by  mastoid  cells  on  all  sides  but  its  roof. 
Most  of  the  mastoid  cells  open  directly  or  indirectly  into  the  antrum 
and  are  lined  by  a  mucosa  continuous  with  and  similar  to  that  of  the 
antrum,  hence  in  inflammation  of  the  latter  the  former  are  secondarily 
involved.  Suppurative  inflammation  of  the  mastoid  antrum  and  cells 
is  one  of  the  most  important  complications  of  middle-ear  disease.  Some 
of  the  more  distant  inferior  cells  are  diploic  spaces  filled  with  red  marrow, 
and  have  no  direct  connection  with  those  above,  but  in  case  of  inflamma- 
tion the  thin  septa  between  may  become  disintegrated.1  Internally  the 
mastoid  cells  come  in  very  close  relation  to  the  sigmoid  groove.  Only  a 
thin  osseous  layer  separates  them,  and  occasionally  this  is  defective.  As 
this  layer  is  perforated,  opposite  the  sigmoid  bend,  by  minute  veins 
leading  from  the  mastoid  antrum  and  cells  to  the  sigmoid  sinus,  throm- 
bosis of  the  latter  may  result  from  inflammation  in  the  former.  In  cases 
where  the  outer  surface  of  the  mastoid  is  perforated,  as  the  result  of  a 
fracture,  or  a  congenital,  or  pathological  loss  of  substance,  emphysema 
may  occur  and  form  a  tumor-like  bulging  (pneumatocele)  over  the 
mastoid,  the  air  coming  from  the  mastoid  cells. 

The  Eustachian  Tube. — The  Eustachian  tube,  connecting  the  tym- 
panum with  the  nasopharynx,  measures  3.5  cm.  (If  in.)  in  length  in 
the  adult  and  half  of  this  in  the  infant,  in  whom  it  is  also  wider.  Its 
direction  is  forward,  with  an  inclination  of  45  degrees  inward  and  40 
es  downward  in  the  adult,  while  in  the  infant  its  downward  inclina- 
tion is  only  10  degrees.  These  facts  explain  the  readiness  with  which 
inflammation  spreads  from  the  pharynx  to  the  middle  ear  and  pus  or 
injected  fluid  in  the  middle  ear  escapes  into  the  pharynx.  As  the  tube  is 
shorter,  wider,  and  more  horizontal  in  infants  and  young  children,  inflam- 
mation spreads  more  easily  from  the  pharynx  to  the  tympanum  in  young 
subjects.  The  tympanic  orifice  of  the  tube  is  on  a  level  with  the  roof  and 
inner  wall  of  the  tympanum  and,  as  it  is  on  a  higher  level  than  the  floor,  it 
not  serve  well  for  drainage.  A  straight  instrument  passed  through 
the  tube  and  on  through  the  tympanum  would  strike  the  joint  between  the 
incus  and  stapes  and  pass  into  the  antrum. 

In  the  adult  the  posterior  one-fourth  of  tube  is  bony,  the  rest  is  cartilagi- 
the  point  of  junction,  the  isthmus,  in  the  petrosquamous  angle, 

irding  to  Zuckerkandl  the  mastoid  colls  an  entirely  air  oelli  In  30.8  per  cent.,  entirely 
in  20  per  cent.,  and  partly  air  and  partly  diploic  oelli  In  42.2  per  oent.  of  all  cases.     In  rare 
the  cells  are  absent  and  the  bono  is  dense  and  sclerosed. 


64  THE  BEAD  AND  NECK 

being  the  narrowest  part  of  the  tube.  A  bougie  1^  mm.  in  diameter 
will  readily  pass  the  isthmus  of  a  normal  tube.  At  the  same  point  the 
tube  bends  slightly,  though  for  practical  purposes  it  may  be  regarded  as 
straight.  In  the  middle  of  its  course  it  lies  close  to  and  parallel  with  the 
carotid  artery,  which  is  internal  to  it.  The  lumen  of  the  bony  portion  is 
always  open,  that  of  the  cartilaginous  part  is  only  open  when  the  palate 
is  raised  during  the  act  of  swallowing,  etc.,  when  air  may  pass  from  the 
pharynx  to  the  tympanum  and  equalize  the  atmospheric  pressure  on  the 
two  sides  of  the  drum  membrane.  When  the  tube  is  obstructed,  as  by 
inflammation  or  a  thickening  of  the  mucosa  or  by  pressure  upon  its 
pharyngeal  orifice,  the  pressure  on  the  outside  of  the  membrane  is  in 
excess,  so  that  the  latter  is  thrust  inward  and  presses  the  stapes  against 
the  fluid  of  the  vestibule,  which  causes  an  annoying  buzzing  or  singing. 
If  the  obstruction  is  but  slight,  the  singing  may  cease  after  an  act  of 
swallowing,  or,  failing  in  this,  by  a  forcible  expiration  while  the  nose  and 
mouth  are  kept  closed  (Valsalva's  method),  or  by  forcibly  inflating  the 
nose  and  nasopharynx  by  a  rubber  air-bag  whose  outlet  is  held  in  one 
nostril  while  the  patient  swallows  a  mouthful  of  water  as  the  bag  is  com- 
pressed (Politzer's  method),  or,  finally,  by  inflation  through  a  Eustachian 
catheter  passed  into  the  pharyngeal  orifice  of  the  tube. 

These  phenomena  are  readily  explained  by  the  anatomical  structure 
of  the  cartilaginous  part  of  the  tube  which  is  made  of  a  plate  of  cartilage 
folded  on  itself,  the  two  borders  of  which  are  joined  by  fibrous  tissue  on  the 
outer  aspect  of  the  tube  to  complete  the  lumen.  To  this  fibrous  portion 
are  attached  fibers  of  the  tensor  palati  and  palatopharyngeus,  so  that  in 
swallowing  or  any  act  involving  the  elevation  of  the  palate,  the  tube  is 
opened  by  their  pulling  the  fibrous  portion  away  from  the  cartilaginous 
portion.  Advantage  is  taken  of  this  by  artillerymen,  who  hold  open  and 
breathe  through  the  mouth  when  a  loud  report  is  expected.  When  we 
breathe  through  the  open  mouth  the  palate  is  kept  elevated,  and,  con- 
sequently, the  Eustachian  tube  is  kept  open,  so  that  the  vibrations  of  the 
air  on  the  membrane  may  be  equalized  by  reaching  it  from  both  sides. 
Thus  not  only  the  painful  shock  of  the  loud  report  is  avoided,  but  even 
the  danger  of  rupturing  the  membrane. 

The  trumpet-shaped  pharyngeal  orifice,  the  largest  part  of  the  tube, 
is  vertically  elongated  and  is  marked  by  a  prominent  ridge  above,  in 
front  and  behind.  Its  position  is  about  at  the  centre  of  the  lateral  aspect 
of  the  nasopharynx,  its  upper  border  being  about  equidistant  and  12  mm. 
(^  in.)  from  the  roof  of  the  pharynx  above,  its  back  wall  behind,  the  level 
of  the  palate  below,  and  the  end  of  the  inferior  turbinate  bone  in  front 
(Tillaux).  It  lies  nearly  directly  above  the  posterior  margin  of  the 
aponeurosis  of  the  soft  palate  and  looks  downward,  inward,  and 
forward.     At  birth  it  is  at  or  below  the  level  of  the  palate. 

With  a  knowledge  of  its  position,  and  remembering  that  it  is  bounded 
above  and  at  the  sides  by  a  projecting  cartilaginous  rim  and  is  open 
below,  we  pass  a  Eustachian  catheter  in  one  of  several  ways:  (1)  After 
passing  it  through  the  inferior  meatus  of  the  nose  with  its  beak  downward 
until  it  touches  the  posterior  wall  of  the  nasopharynx,  the  beak  is  turned 


THE  FACE  .  05 

outward  and  the  catheter  is  slowly  withdrawn  about  1  cm.  until  it  is  felt 
to  glide  over  the  projecting  posterior  rim  of  the  opening,  when  it  is  turned 
still  farther,  until  the  beak  and  the  ring  on  the  handle  point  to  the  outer 
canthus  of  the  eye.  (2)  After  reaching  the  posterior  wall  of  the  naso- 
pharynx the  beak  is  turned  inward  and  the  catheter  withdrawn  until  its 
beak  catches  on  the  posterior  border  of  the  nasal  septum,  when  the 
catheter  is  rotated  through  a  semicircle  so  that  the  beak,  gliding  over  the 
upper  surface  of  the  soft  palate,  enters  the  Eustachian  orifice  on  its  lower 
or  open  side.  The  curve  of  the  catheter  is  such  that  when  the  curved 
portion  catches  on  the  septum  the  tip  will  be  far  enough  behind  the  mar- 
gin of  the  hard  palate  to  enter  the  Eustachian  orifice.  We  may  also  with- 
draw the  catheter  with  its  beak  down  until  the  latter  catches  on  the  pos- 
terior margin  of  the  hard  palate  and  then  rotate  outward  through  90 
degrees,  but  this  plan  is  not  so  sure  on  account  of  the  difficulty  of  dis- 
tinguishing between  the  posterior  margins  of  the  hard  palate  and  of  the 
aponeurosis  of  the  soft  palate. 

Just  behind  the  prominence  caused  by  the  pharyngeal  orifice  is  a 
depression  in  the  wall  of  the  pharynx,  the  fossa  of  Rosenmiiller.  This 
may  be  mistaken  for  the  opening  of  the  tube,  for  it  may  readily  engage 
the*  tip  of  the  catheter,  and  it  is  the  principal  cause  of  error  in  passing 
the  catheter.  When  the  catheter  is  in  Rosenmuller's  fossa,  the  patient 
gives  a  sudden  start  when  air  is  forced  through  it,  but  when  the  catheter 
is  in  the  Eustachian  tube  the  surgeon  can  hear  the  entrance  of  air  into  the 
ear  by  means  of  a  tube  passing  between  the  patient's  meatus  and  his  own. 
This  fossa  is  greatly  deepened  when  the  pharyngeal  (Luschka's)  tonsil, 
internal  to  it,  is  enlarged. 

In  cases  of  deafness  associated  with  hypertrophy  of  the  tonsil,  which 
lies  Mow  the  soft  palate,  the  obstruction  of  the  tube  is  not  due  to  the 
bressure  of  the  enlarged  tonsil  itself,  but  to  the  associated  hypertrophy  of 
die  adenoid  tissue  about  and  within  the  orifice  of  the  tube.  The  hyper- 
trophied  tonsil  may  hinder  the  opening  of  the  tube  by  pressing  up  the 
palate  and  thus  relaxing  the  tensor  palati  muscle.  The  movement  of  the 
cilia  of  the  epithelium  which  lines  the  tube  is  toward  the  pharynx.  The 
lymphatics  of  the  external  and  middle  ear  and  of  the  Eustachian  tube 
enter  nodes  near  the  angle  of  the  jaw. 


THE  FACE. 

Region  of  the  Orbit  and  Eye. 

The  Eyebrows.  The  eyebrows  are  composed  of  layers  similar  to  those 
of  the  scalp  except  that  the  subcutaneous  layer  contains  but  little  fat  and 
the  muscular  layer  includes  three  intersecting  muscles,  the  corrugator 
mpercilii,  the  occipitofrontalis,  and  the  orbicularis  palpebrarum  muscles. 

incisions  made  here  should  be  parallel  to  the  long  axis  of  the  eyebrow 

so  that  the  cicatrix  may  be  hidden  in  the  hairs.     Blows  or  falls  may  pro- 
iuce  a    wound  made  by  the  supra-orbilal  margin  cutting  through   from 


66  THE  HEAD  AND  NECK 

within  and  often  appearing  like  an  incised  wound.  The  eyebrows, 
especially  their  inner  end  or  head,  correspond  to  the  frontal  sinuses. 
The  outer  end  or  tail  of  the  eyebrows,  at  the  level  of  the  external  angular 
process,  is  a  favorite  situation  for  small  dermoid  cysts,  which  are  here  due 
to  a  portion  of  skin  being  included  beneath  the  surface  in  the  closure  of 
the  outer  end  of  the  orbitonasal  fissure.  Such  cysts  may  occur  at  other 
points  along  this  fissure.  They  are  beneath  and  do  not  involve  the  skin 
and  often  indent  the  bone.  The  hairs  of  the  eyebrows  help  to  shade  the 
eyes,  to  protect  them  from  dust,  and  to  deflect  the  perspiration  of  the 
forehead  beyond  their  limits.  The  corrugator  muscle  is  supplied  by  the 
facial  nerve  and  is  affected  in  facial  paralysis.  The  lymphatics  of  the  outer 
half  run  to  the  parotid  nodes,  those  of  the  inner  end  to  the  submaxillary 
nodes. 

The  Eyelids  (Fig.  22). — The  eyelids  serve  to  cover,  protect  and  keep 
moist  the  eyes.  Examining  the  component  layers  successively,  we  find 
that  (1)  the  skin  is  very  thin  and  delicate  so  that  extravasation  of  blood 
beneath  it  shows  through  as  a  "black  eye"  almost  at  once.  It  presents 
numerous  transverse  folds,  in  line  with  which  all  incisions  in  the  lid  should 
be  made.  These  folds  are  most  marked  beyond  the  tarsal  cartilages,  and 
in  the  upper  lid  one  deeper  than  the  rest  {superior  palpebral  fold)  divides 
the  lid  into  two  parts,  a  lower  smoother  tarsal  portion  covering  the  globe, 
and  an  upper  more  wrinkled  orbital  portion  covering  the  soft  parts  of  the 
orbit.  The  folds  of  skin  are  due  to  its  laxity  and  its  loose  attachment 
to  the  muscular  layer  by  (2)  a  thin  layer  of  fatless  connective  tissue. 
The  laxity  of  the  skin  makes  it  well  adapted  for  plastic  operations.  By 
reason  of  its  loose  attachment  it  is  readily  affected  by  the  traction  of 
cicatrices  below  the  lower  lid,  which  draw  the  latter  away  from  the 
globe  and  thus  produce  ectropion  or  eversion  of  the  lid.  Epithelioma 
frequently  attacks  the  lids  and  may  in  time  produce  ectropion.  The 
skin  contains  some  pigment,  which  helps  to  protect  the  eye  from  bright 
light,  and  the  yellowish  plaques  sometimes  seen  in  the  skin  in  old  people, 
especially  near  the  inner  can  thus,  are  due  to  an  accumulation  of  sebaceous 
matter  in  the  numerous  sebaceous  glands. 

3.  The  orbicularis  palpebrarum,  or  sphincter  muscle  of  the  lids,  by  its 
action  closes  the  lids,  raising  the  lower  and  depressing  the  upper  one. 
As  it  is  attached  internally  to  the  firm  tendo  oculi,  its  contraction  draws 
inward  the  outer  commissure,  which  is  attached  externally  by  the  less 
firm  external  tarsal  ligament.  This  inward  motion  of  the  eyelids  helps  to 
wash  the  lacrymal  secretion  toward  the  inner  canthus  and  the  puncta 
lacrymalia  and  to  clear  the  eye  of  dust.  The  muscle  is  supplied  by  the 
facial  nerve,  in  paralysis  of  which  the  ability  to  wink  or  close  the  eyelids 
is  lost.  Hence  the  importance  of  sparing  this  branch  of  the  nerve  in  any 
peripheral  operation  for  tic  douloureux  if  the  operation  on  the  ganglion 
may  be  subsequently  demanded,  for  this  operation  anesthetizes  the  con- 
junctiva (see  foot  note,  pp.  68  and  78).  The  contracture  of  the  muscle 
(blepharospasm)  closes  the  lids  continuously,  and  may  reach  such  a  degree 
as  to  invert  the  free  border  of  the  lids  (entropion),  the  pressure  of  which 
may  occasion  ulceration  of  the  cornea. 


THE  FACE 


67 


4.  Separating  the  muscle  from  the  tarsal  cartilages  is  a  thin,  loose 
connective-tissue  layer.  This  is  readily  infiltrated  by  edema,  inflammatory 
or  bloody  exudation,  etc.,  which  cause  a  rapid  and  considerable  swelling 
of  the  lids.  In  the  puffiness  of  the  lids  so  common  in  Bright's  disease  and 
some  other  conditions  the  swelling  is  largely  in  this  layer.  This  layer 
also  includes  fibers  from  the  fibrous  expansion  of  the  levator  palpebral 
muscle  in  the  upper  lid  and  of  the  corresponding  rectus  muscle  in  both 
lids. 


UPPER     MARGIN    OF    ORBIT 


.land  of  moll 
:ilial 

Upper  lid  in  sagittal  section.   (After  Merkel  ) 


.").  The  stiff  plate  <>!'  closely  felted  connective  tissue  called  the  "tarsal 
cartilages"  form  (he  framework  of  (hose  parts  of  (he  lids  which  cover  (he 
globe.  The  opposing  margins  ace  free,  except  internally  and  externally, 
wh<n-  they  unite  to  form  (he  canthi,  (lie  outer  margins  are  connected 
with  tin-  periosteum  ;it.  (he  margin  of  the  orbit  by  the  palpebral  fascia. 

The  latter  cover    the    oft  parts  of  the  orbit  and  is  linn  enough  to  prevent 


68  THE  HEAD  AND  NECK 

an  extravasation  within  the  orbit  from  reaching  the  surface  of  the  eyelids. 
The  breadth  of  the  upper  tarsus  (10  mm.)  is  about  double  that  of  the  lower, 
and  opposes  the  examination  of  the  inner  surface  of  the  upperlid,  while  the 
inner  surface  of  the  lower  lid  is  readily  exposed  by  drawing  down  that  lid. 
To  expose  the  inner  surface  of  the  upper  lid,  as  in  the  search  for  foreign 
bodies,  we  direct  the  patient  to  look  down,  and  then  seize  the  eyelashes 
and  the  edge  of  the  lid  and  evert  it  by  raising  up  the  free  border  while 
the  middle  of  the  lid  is  pressed  down  by  a  match,  small  pencil,  etc. 
Attached  to  the  upper  border  of  the  upper  tarsus,  and  its  anterior  surface 
just  below  this  point,  is  the  levator  muscle  which  raises  this  lid.  As  it  is 
supplied  by  the  third  nerve,  this  lid  droops  (ptosis)  when  that  nerve  is 
paralyzed.  Incisions  to  reach  the  cavity  of  the  orbit  are  made  beyond  the 
limits  of  the  tarsi,  through  the  palpebral  fascia,  usually  that  of  the  upper 
lid.  The  two  tarsi,  where  they  join  internally  and  externally,  are  con- 
nected with  the  inner  and  outer  orbital  margins  by  the  palpebral  liga- 
ments. Of  these,  the  inner,  tendo  oculi,  is  attached  by  two  limbs  to  the 
two  ridges  bounding  the  lacrymal  groove,  and  thus  embraces  the  lacry- 
mal  sac,  to  which  it  is  an  important  guide.  It  lies  in  front  of  and  external 
to  the  lacrymal  sac  at  the  junction  of  its  middle  and  upper  thirds  and  can 
be  made  prominent  by  drawing  the  lid  outward. 

6.  The  conjunctival  mucous  membrane  adheres  closely  to  the  back  of 
the  tarsi  (palpebral  conjunctiva).  This  part  of  it  is  thick,  red,  and  vas- 
cular, and  its  degree  of  redness,  in  the  absence  of  inflammation,  is  taken 
as  an  indication  of  the  presence  or  absence  of  anemia.  In  the  eye  method 
of  the  tuberculin  diagnostic  test  the  same  sign  indicates  that  the  patient 
has  a  tuberculous  process.  In  granular  lids  the  little  elevations  known 
as  granulations  are  due  to  nodules  of  adenoid  tissue,  enlarged  mucous 
follicles,  and  papillae.  From  the  contraction  of  the  new  connective  tissue 
found  abundantly  in  the  membrane  in  such  conditions  the  conjunctiva 
is  puckered  and  the  edge  of  the  lids  may  be  inverted  (entropion).  A 
similar  result  follows  from  the  specific  chronic  conjunctivitis  known  as 
trachoma.  The  rich  sensory  nerve  supply,  from  the  ophthalmic  division 
and  the  infra-orbital  branch  of  the  fifth  nerve,  explains  the  exquisite 
pain  caused  by  conjunctivitis  or  the  presence  of  a  foreign  body.1 

The  conjunctiva  is  reflected  from  the  back  of  the  lids  onto  the  surface 
of  the  globe,  the  anterior  third  of  which  it  covers,  up  to  the  edge  of  the 
cornea. 

The  point  of  this  reflection  is  called  the  fornix.  The  upper  fornix  is 
the  deeper,  extending  above  the  corresponding  tarsus  to  the  junction  of 
the  inferior  three-fourths  with  the  superior  fourth  of  the  upper  lid. 
Hence  incisions  to  reach  the  orbital  contents  are  made  in  the  upper 
fourth  of  the  lid  so  as  to  avoid  the  conjunctiva.  The  external  canthus 
is  several  millimeters  from  the  outer  margin  of  the  orbit  and  the  con- 
junctiva extends  beneath  the  lids  here  as  an  external  cul-de-sac  or  fornix. 
It  is  in  one  of  the  cul-de-sacs,  superior,  external,  or  inferior,  that  foreign 

1  After  the  operation  of  removal  of  the  Gasserian  ganglion  the  loss  of  sensation  of  the  conjunctiva 
renders  the  presence  of  dust  and  foreign  bodies  painless,  but  at  the  same  time  the  latter  set  up  an 
inflammation  of  the  conjunctiva,  so  that  the  eye  may  have  to  be  kept  closed  and  protected. 


THE  FACE  69 

bodies  are  likely  to  be  lodged.  To  discover  and  remove  such  bodies  the 
inferior  and  external  fornices  can  be  readily  explored  by  drawing  the  lids 
downward  or  outward  respectively,  while  the  upper  fornix  may  be 
explored  by  everting  the  lid  as  described  above,  or  the  foreign  body  may 
often  be  removed  by  pulling  down  the  upper  lid  so  that  its  inner  surface 
i^  wiped  off  on  the  outer  surface  of  the  lower  lid.  At  the  inner  canthus, 
which  reaches  to  the  inner  margin  of  the  orbit,  is  an  island  of  modified 
skin,  the  caruncle,  and  external  to  this  the  conjunctiva  presents  a  small 
vertical  semilunar  fold,  the  homologue  of  the  third  eyelid  or  membrana 
nictitans  of  birds. 

The  conjunctiva  covering  the  globe  (ocular  conjunctiva)  is  thin  and 
loosely  attached  so  that  it  is  freely  movable.  This  permits  of  free  move- 
ment of  the  ball  and  is  of  great  value  in  some  operations.  Some  of  the 
vessels  seen  through  the  ocular  conjunctiva  belong  to  the  underlying 
sclerotic,  as  can  be  shown  by  their  remaining  stationary  when  the  con- 
junctiva is  moved  over  them.  This  part  of  the  conjunctiva  has  but  little 
vascularity,  unless  it  is  inflamed,  so  that  the  white  color  of  the  sclerotic 
shows  through  it.  The  looseness  of  the  subconjunctival  tissue  over  the 
globe  favors  the  development  of  edema,  which  may  reach  such  an  extreme 
degree  that  the  eye  cannot  be  closed,  and  the  cornea  is  partly  or  entirely 
covered.  It  also  favors  the  occurrence  of  subconjunctival  ecchymoses 
which  may  be  due  to  the  giving  way  of  one  of  the  poorly  supported  vessels, 
as  in  severe  vomiting  or  a  paroxysm  of  whooping  cough,  or  to  an  extra- 
vasation, as  from  a  fracture  of  the  base  of  the  skull  involving  the  orbital 
roof.  One  peculiar  feature  of  subconjunctival  ecchymoses  is  the  fact  that 
they  retain  their  scarlet  color,  owing  to  the  thinness  of  the  conjunctiva 
which  allows  the  air  to  reach  the  blood  and  keep  it  oxygenated.  Although 
the  conjunctiva  is  normally  very  thin,  it  may  hypertrophy  in  the  form  of  a 
vascular  triangle  (pterygium),  the  base  of  which  is  directed  toward  one  of 
the  canthi,  the  apex  to  and  finally  over  the  pupil. 

The  arteries  of  the  eyelids,  derived  from  the  lacrymal  and  palpebral 
branches  of  the  ophthalmic,  form  arches  near  the  free  borders  of  the  tarsi 
in  the  connective-tissue  layer  beneath  the  muscle.  The  veins  enter  into 
branches  of  the  ophthalmic  veins  at  the  outer  canthus  and  into  the  veins 
of  the  face  at  the  inner  canthus.  Thus  the  veins  of  the  eyelid,  and  through 
them  those  of  the  face,  communicate  with  the  cavernous  sinus  through  the 
ophthalmic  vein,  so  that  an  infection  of  the  eyelid  or  face  is  capable  of 
causing  septic  thrombosis  of  the  cavernous  sinus. 

The  free  border  of  the  eyelids,  averaging  3  cm.  (1  i  in.)  in  length,  con- 
of  a  ciliary  portion  (outer  five-sixths)  and  a  lacrymal  portion 
'inner  one-sixth)  separated  by  the  projecting  papilla  on  which  is  the 
punctum.  The  ciliary  portion  is  flattened  and  2  mm.  thick.  The  two 
or  three  rows  of  obliquely  Implanted  hairs  which  it  presents  anteriorly 
may  occasionally  project  internally  and  irritate  the  conjunctiva  and 
cornea.    This  may  be  due  to  a  vicious  implantation  (trichiasis)  or  to  a 

general  inversion   of  the  border  (entropion).     Inflaninia tion  in  theseba- 

.rl;uMl   of  the  hair  follicles  constitutes  ;i  "stye."  The  secretion  of  the 
Meibomian  glands  lubricates  the  cornea  and  renders  it  waterproof.    When 


70 


THE  HEAD  AND  NECK 


this  secretion  is  retained  in  one  of  the  glands  it  gives  rise  to  a  "tarsal 
tumor"  or  chalazion.  The  border  of  the  lid,  with  its  sluggish  terminal 
circulation,  its  junction  of  skin  and  mucous  membrane,  its  moist  surface 
and  numerous  glands,  is  frequently  the  seat  of  troublesome  inflammation. 
The  Lacrymal  Apparatus. — The  Lacrymal  Gland. —  The  lacrymal 
gland,  lying  within  the  orbit,  reaches  to  within  a  few  millimeters  of 
the  anterior  orbital  margin  at  its  upper  and  outer  angle,  and  lies  between 
the  superior  and  external  recti.  It  is  enclosed  in  a  fibrous  capsule 
derived  from  the  orbital  periosteum,  so  that,  according  to  Tillaux,  it 
may  be  opened  or  removed  without  opening  the  postocular  space,  by 
incising  the  periosteum  at  the  margin  of  the  orbit  and  stripping  it  off 
from  the  roof  until  we  reach  a  point  just  above  the  gland.  Cysts, 
tumors,  and  abscesses  occasionally  occur  here.  A  lower  accessory  portion 
of  the  gland  lies  above  the  outer  third  of  the  upper  conjunctival  fornix, 
where  also  the  ducts  of  the  gland  open.  From  this  point  the  tears, 
neutral  in  reaction,  fall  over  the  front  of  the  eyeball,  flushing  it  of  dust, 
etc.,  and  are  swept  inward  to  the  puncta  by  the  contractions  of  the 
orbicularis  muscle  in  winking. 

Each  papilla  curves  backward  to  the  surface  of  the  eye  and  presents 
at  its  summit  the  punctum  or  commencement  of  the  canaliculus  (Fig.  24). 

The  position  of  the  puncta  in  close 
fig  23  apposition    with  the    eye  is   well 

adapted  for  draining  off  the  tears 
which  collect  here.  Sometimes  the 
puncta  are  displaced  forward,  so 
that  the  tears  collect  and  overflow 
onto  the  cheek  (epiphora).  This 
may  occur  when  the  lower  punc- 
tum only  is  displaced,  as  in  swelling 
of  the  lid,  entropion,  or  ectropion. 
Among  the  causes  of  the  latter  is  a 
relaxed  condition  of  the  orbicularis, 
present  in  old  age  or  in  facial 
paralysis  when  this  muscle  is  para- 
lyzed, for  the  puncta  and  inner 
margin  of  the  lids  are  held  in  appo- 
sition with  the  surface  of  the  globe 
by  a  specialized  part  of  the  orbicu- 
laris muscle  known  as  the  muscle 
of  Horner  or  the  tensor  tarsi.  This 
muscle  arises  from  the  lacrymal 
bone,  behind  the  posterior  or  reflected  limb  of  the  tendo  oculi,  and  from  the 
latter  and  is  attached  to  the  back  of  the  inner  end  of  the  tarsi  as  far  as  the 
papillae  (Fig.  23).  By  drawing  inward  and  backward  the  outer  end  of 
the  tendo  oculi,  and  thereby  the  tarsi,  it  may  also  compress  the  lacrymal 
sac.     It  may  also  help  to  open  or  keep  open  the  canaliculi. 

The  lower  punctum  is  slightly  external  to  and  larger  than  the  upper, 
and  both  are  held  open  by  a  firm  fibrous  ring.    The  canaliculi  run  at 


Horizontal  section  of  lacrymal  sac  passing 
through  the  tendo  oculi.  Diagrammatic:  a, 
periosteum;  b,  lacrymal  sac;  c,  tendo  oculi; 
d,  canaliculus;  e,  caruncle;  f,  inferior  punctum; 
g,  tendo  oculi,  reflected  portion;  h,  muscle  of 
Horner.     (Testut.) 


THE  FACE 


71 


first  vertically  and  then  bend  sharply  and  run  nearly  horizontally  inward, 
a  point  to  be  remembered  in  passing  a  stylet  or  in  injections.  Obstruction 
of  the  puncta  or  canaliculi,  due  to  the  swelling  or  the  compression  of  an 
inflammation,  is  another  cause  of  the  overflow  of  tears. 

The  Lacrymal  Sac. — The  lacrymal  sac,  lodged  in  the  lacrymal  groove, 
just  internal  to  the  inner  canthus,  receives  the  canaliculi  antero- 
externally  and  has  the  following  landmarks:  The  inner  ridge  bounding 
the  lacrymal  groove  is  continuous  with  the  inferior  orbital  margin,  and 
can  be  palpated.  By  drawing  the  eyelids  externally  the  tendo  oadi  can 
be  seen  and  felt  crossing  in  front  of  the  sac  at  the  junction  of  its  upper 
and  middle  thirds.  Consequently  it  is  below  the  tendo  oculi  and  exter- 
nal to  the  above  ridge  that  we  incise  to  open  the  antero-external  aspect 


Fig.  24 


PENING    OF    CANALIC. 
INTO    LACHRYMAL   SAC 


NF.   ORIFICE    OF 

NASAL    DUCT 
NF.  TURBINATE    BONE 


Transverse  oblique  section  through  nasal  canal,  viewed  from  in  front.     (Testut.) 


of  the  lacrymal  sac,  in  case  of  lacrymal  tumor,  to  give  vent  to  pus  or 
to  introduce  instruments.  A  lacrymal  abscess  always  points  below  the 
tendon.  In  introducing  stylets,  etc.,  it  is  important  to  know  the  course 
and  direction  of  the  lacrymal  sac  and  its  continuation,  the  nasal  duct. 
These  together  are  not  quite  straight,  but  slightly  curved  so  as  to  be  con- 
posteriorly,  and  are  directed  downward,  backward,  and  slightly 
outward  in  a  line  from  the  inner  eanthus  to  the  front  of  the  first  molar 
tooth.  Together  tlnv  average  a  little  over  2(>  mm.  (1  in.)  in  length, 
of  which  the  sac  represents  the  upper  two-fifths.  Lacrymal  tumor  is 
usually  due  to  a  chronic  inflammation  and  thickening  of  the  lining 

mucous  membrane.      It  forms  a  swelling  at  (lie  inner  corner  of  flic  orbit, 

and  it-;  evacuation  is  occasionally  followed  bya  lacrymal  fistula.     Valves 
DCCUr,  hill  are  not  constant,  at  the  opening  of  the  canaliculi  info  the  sac 


72  THE  HEAD  AND  NECK 

and  between  the  sac  and  the  nasal  duct.  According  to  some  the  latter, 
which  is  the  less  constant  valve,  may  be  responsible  for  some  cases  of 
lacrymal  tumor. 

The  lacrymal  sac  is  enclosed  by  a  fibrous  sheath  derived  from  the 
splitting  of  the  periosteum  at  the  ridges  which  bound  its  groove.  This 
sheath  limits  the  distention  of  the  sac  which  may  reach  6  mm.  Q-  in.) 
anteroposteriorly  and  4  mm.  transversely.  The  nasal  duct,  lodged  in  the 
lacrymal  canal,  is  about  3  mm.  (|  in.)  in  diameter,  and  its  narrowest 
point  is  at  the  junction  with  the  sac.  It  is  the  unobliterated  part  of  the 
orbitonasal  fissure,  and  open",  by  a  vertical  slit-like  opening  into  the 
inferior  meatus  of  the  nose.  It  is  difficult  to  find  and  enter  this  opening 
in  the  cadaver,  hence  catheterization  from  below  in  the  living  subject  is 
too  difficult  to  be  advisable.  This  lower  opening  is  situated  about  3  cm. 
(li=-  in.)  behind  the  free  margin  of  the  ala  of  the  nose,  8  to  10  mm.  (^  in.) 
behind  the  anterior  end  of  the  inferior  turbinate  bone,  in  the  angle 
between  the  short,  oblique,  anterior  limb  and  the  longer  and  more  hori- 
zontal posterior  limb  of  this  bone,  and  in  the  angle  between  the  lateral 
wall  of  the  nose  and  the  inferior  turbinate  bone. 

All  the  ducts  by  which  the  tears  are  removed  are  held  open,  the  puncta 
by  the  fibrous  rings  surrounding  them,  the  canaliculi  by  the  tensor  tarsi 
muscle,  the  lacrymal  sac  by  its  fibrous  sheath  and  the  tendo  oculi,  the 
nasal  duct  by  its  bony  walls.  This  circumstances  favors  the  theory  of 
Sedillot,  which  explains  the  passage  of  tears  by  the  vacuum  produced  by 
the  air  passing  across  the  lower  opening  of  the  duct  on  the  principle  of 
the  mercury  vacuum  pump.  It  may  also  be  said  that  the  process  of 
winking,  due  to  the  action  of  the  orbicularis,  keeps  the  puncta  applied 
to  the  eye,  holds  open  the  canaliculi  by  means  of  the  tensor  tarsi,  and 
compresses  the  sac  so  as  to  force  the  tears  downward,  as  the  opening 
into  the  canaliculi  is  guarded  by  a  valve.  After  such  a  compression  the 
emptied  sac  exerts  a  suction  to  draw  the  tears  into  it.  By  means  of  these 
ducts  the  mucous  membrane  of  the  nose  and  eye  are  continuous  and 
inflammation  may  spread  from  one  to  the  other.  Inflammation  of  the 
sac  and  duct  is  usually  an  extension  from  an  inflammation  of  the  nasal 
mucosa. 

The  Orbit. — The  anteroposterior  axis  of  the  pyramidal  orbital  cavity 
is  directed  obliquely  forward  and  outward  and  measures  4.5  cm.  (If  in.). 
The  inner  walls,  though  convex  laterally,  are  nearly  parallel  with  one 
another,  a  condition,  like  that  of  the  parallelism  of  the  optic  axes,  which 
is  peculiar  to  man.  The  inner  wall,  floor,  and  roof  are  very  thin.  The 
inner  wall  separates  the  orbit  from  the  ethmoid  cells  and  nasal  fossa,  the 
floor  from  the  maxillary  antrum,  and  the  roof  from  the  cranial  cavity. 
Foreign  bodies,  such  as  foils,  umbrellas,  canes,  or  sharp  sticks,  thrust 
into  the  orbit  have  readily  penetrated  through  these  thin  walls  into  the 
ethmoidal  cells,  the  nose,  the  antrum,  or  the  cranial  cavity.  These  walls 
offer  little  resistance  to  tumors  extending  into  the  orbit  from  the  sur- 
rounding cavities,  or  vice  versa.  This  is  especially  seen  in  tumors  of  the 
antrum  which  elevate  the  floor  of  the  orbit,  destroy  the  intervening  bone, 
and  displace  forward  the  orbital  contents,  causing  exophthalmos. 


PLATE  II 


FIG.  25 


LEVATOR     PALPE- 
SUP.    RECTUS     |3RAE    MUSCLE 
MUSCLE 


INT.    RECTUS        \\l'M/ 


MUSCLE 
ETHMOID 
CELLS 


TEMPORAL    MUSCLE 

LACHRYMAL    GLAND 
EXT.    RECTUS 


$^1  flT"   MUSCLE 

'.//         '       Ml  1NF"   OBLIQU 


INF.    RECTUS 

MUSCLE       INFRAORBI 
TAL    NERVE 


Frontal  Section  of  the  Left  Eye.     (Merkel.) 


TENDON  OF  INT 
RECTUS    MUSC 

SHEATH  OF  INT 
RECTUS    MUSC 


Partly  Diagrammatic  Horizontal  Section  of  the  Right  Orbit 
and  Eye,  to  show  the  arrangement  of  the  capsule  of  Tenon. 
L'.wer  segment  of  the  section.     (Testut.) 


THE  FACE  73 

The  presence  of  the  bony  groove  and  canal  for  the  infra-orbital  nerve 
in  the  floor  of  the  orbit  should  be  borne  in  mind,  for  the  nerve  is  liable 
to  be  pressed  upon  by  tumors  of  the  orbit  or  antrum.  There  are  various 
channels  of  communication  between  the  orbit  and  the  surrounding 
cavities.  It  communicates  with  the  cranial  cavity  through  the  optic 
foramen  and  the  sphenoidal  fissure  at  the  apex  of  the  orbit,  with  the 
nose  through  the  nasal  duct,  and  with  the  zygomatic  and  sphenomax- 
illary fossae  through  the  sphenomaxillary  fissure.  Through  this  fissure 
blood  may  find  its  way  into  the  orbit  after  violent  blows  on  the  temporal 
region. 

At  each  angle  between  the  orbital  walls  there  is  some  point  of 
interest.  Thus,  at  the  supero-internal  angle  are  the  ethmoidal  canals 
(and  the  pulley  for  the  superior  oblique);  at  the  infer o-internal  angle, 
the  lacrymal  canal;  at  the  infero-extemal  angle  the  sphenomaxillary 
fissure;  and  at  the  supero-external,  the  depression  for  the  lacrymal 
gland.  The  anterior  end  of  the  sphenomaxillary  fissure,  through  which 
we  pass  the  flexible  saw  in  removal  of  the  upper  jaw,  is  15  mm.  (1  in.) 
from  the  margin  of  the  orbit.  The  outer  walls  are  inclined  to  the  sagittal 
plane  at  an  angle  of  nearly  45  degrees,  hence  the  interior  of  the  orbit  is 
most  conveniently  reached  by  incisions  external  to  the  globe  between  it 
and  the  outer  wall.  The  bones  of  the  orbit  are  especially  liable  to  develop 
"ivory"  exostoses.  The  largest  part  of  the  orbit  is  not  at  its  margin,  but 
about  1  cm.  behind  it. 

The  orbital  margin  is  prominent  and  easily  felt  above,  below,  and  exter- 
nally, more  rounded  and  less  readily  palpable  internally.  The  eye  is 
well  protected  by  this  prominent  rim.  As  the  base  of  the  orbit  is  bevelled, 
so  that  the  plane  of  its  margin  looks  outward  as  well  as  forward,  the 
range  of  vision  is  notably  increased  laterally,  but  at  the  same  time  the 
eye  is  more  vulnerable  from  the  outside.  On  this  side  the  globe  may 
be  palpated  as  far  back  as  its  equator.  Mesially  the  eye  is  protected 
from  injury  mainly  by  the  nose.  On  the  supra-orbital  margin  at  the 
junction  of  the  inner  and  middle  thirds  is  the  supra-orbital  notch,  or 
foramen,  through  which  the  supra-orbital  nerve  emerges  from  the  orbit. 
The  horizontal  diameter  of  the  orbital  margin  is  about  3.7  cm.  (1^  in.), 
its  vertical  diameter  a  little  over  3  cm.  (1\  in.);  the  similar  diameters  of 
tin*  globe  are  respectively  24  and  23  mm. 

The  Contents  of  the  Orbit.  About  one-fifth  of  the  space  is  occupied 
by  the  globe,  the  remainder  by  its  vessels,  nerves,  and  muscles,  embedded 
in  a  quantity  of  fat  (Fig.  25).  In  addition  there  is  an  important  apo- 
neurotic capsule,  supporting  flic  globe  and  limiting  the  action  of  its 
muscles.  This  is  the  capsule  of  Tenon  or  orbital  aponeurosis,  whose  pro- 
longations conned  it  with  the  muscle  sheaths  and  the  orbital  periosteum 
(Fig.  26).  The  capsule  of  Tenon  proper  is  that  part  of  the  fascia  of  the 
orbit  which  surrounds  the  posterior  ',  or  the  sclerotic  portion  of  the 
(riobe.  It  extends  forward  as  far  as  the  cornea,  joining  with  the  con- 
junctiva, and  is  continued  backward  around  the  optic  nerve,  whose 
sheath  it  invests.  In  order,  therefore,  to  reach  the  sclerotic  in  a  tenotomy 
of  the   recti    tendons   tor  strabismus,    we  must  cut  through  two  layers, 


74  THE  HEAD  AND  NECK 

the  ocular  conjunctiva  and  Tenon's  capsule.  This  capsule  separates 
the  globe  from  the  fat,  etc.,  in  the  posterior  half  of  the  orbit;  in  fact, 
with  its  prolongations  it  forms  a  kind  of  septum  between  the  globe  in 
front  and  the  rest  of  the  orbital  contents  behind.  The  inner  surface  of 
this  capsule  is  loosely  connected  with  the  sclerotic  by  lax  and  delicate 
areolar  tissue  and  is  smoothly  lined  by  endothelium.  It  is,  in  fact,  the 
outer  wall  of  a  large  lymph  space  (Tenon's  space),  and  forms  a  species 
of  socket  in  which  the  globe  moves  without  friction. 

In  order  to  reach  their  insertions  in  the  sclerotic  coat  of  the  globe 
the  tendons  of  the  ocular  muscles  must  pass  through  this  capsule.  Where 
they  do  so,  opposite  the  equator  of  the  globe,  the  aponeurosis  invests 
the  muscle  tendons  in  a  fibrous  sheath  which  is  prolonged  forward  to  their 
insertions  and  backward  toward  the  middle  of  the  orbit,  where  it  fuses 
with  the  proper  sheaths  of  the  muscles.  A  small  serous  bursa  is  formed 
on  the  anterior  surface  of  each  tendon.  In  consequence  of  this  arrange- 
ment of  the  prolongations  of  the  capsule  the  muscles  do  not  retract  to 
their  limit  after  division  of  their  tendons,  close  to  their  sclerotic  insertion, 
but  are  held  by  the  capsular  prolongation.  In  this  way,  after  tenotomy, 
the  muscles  retain  a  hold  on  the  globe  so  that  they  still  act  on  it  through 
the  capsule.  Even  after  enucleation  of  the  globe  the  muscles  retain  a 
hold  on  the  capsule,  and  so  may  furnish  some  motion  to  the  stump  and 
the  artificial  eye  which  rests  on  it.  This  movement  is  more  complete  if 
the  sclerotic  coat  is  preserved.  In  addition,  prolongations  pass  from  the 
aponeurotic  sheaths  of  the  recti  to  the  walls  of  the  orbit  a  little  behind  their 
margins,  where  they  are  continuous  with  the  orbital  periosteum.  Of  these 
prolongations  or  bands  the  external  and  internal,  from  the  sheaths  of  the 
corresponding  recti  to  the  orbital  walls  behind  the  corresponding  pal- 
pebral ligaments,  are  the  best  developed.  They  are  known  as  the  check 
ligaments,  for  they  check  excessive  outward  and  inward  rotation  of  the 
globe.  Together  with  that  part  of  the  capsule  connecting  them  beneath 
the  globe,  they  have  been  called  by  Lockwood  the  suspensory  ligament, 
as  they  suspend  the  globe  as  in  a  hammock.  According  to  Lockwood, 
it  is  important  to  preserve  the  attachments  of  this  ligament  in  removing 
the  maxilla,  in  order  to  prevent  the  eyeball  from  sinking  downward. 
The  orbital  band  or  prolongation  from  the  superior  rectus  to  the  orbital 
walls  connects  the  latter  muscle  with  the  levator  palpebral  just  above  it. 
Hence  the  contraction  of  these  muscles  is  not  entirely  independent,  and 
the  superior  rectus  is  to  a  slight  extent  an  elevator  of  the  upper  lid,  so 
that  elevation  of  the  eye  and  of  the  lid  are  very  intimately  associated 
with  one  another. 

The  attachment  of  the  recti  muscles  to  the  orbital  walls  by  means  of 
the  prolongations  from  their  aponeurotic  sheaths  has  the  following 
practical  consequences.  The  muscles  do  not  retract  far  when  divided, 
and  they  are  held  away  from  the  globe  by  these  prolongations,  which 
act  like  pulleys,  so  that  the  muscles  when  they  act  do  not  compress  the 
globe  as  they  otherwise  would.  Furthermore,  on  account  of  the  obliquely 
forward  direction  of  these  prolongations,  the  recti,  when  they  act,  do  not 
retract  the  globe  as  much  as  they  otherwise  would,  and  hence  do  not 


THE  FACE  75 

overpower  the  oblique  muscles,  which  act  weakly  as  protrusors.  In 
this  way  the  action  of  the  recti  is  confined  to  the  movements  of  the 
globe  on  its  various  axes. 

The  periosteum  lining  the  orbit  is  continuous  at  the  orbital  margin 
with  that  of  the  surface  of  the  face  and  cranium  and  at  the  sphenoidal 
fissure  and  the  optic  foramen  with  the  periosteal  layer  of  the  dura. 

The  Muscles. — The  muscles  of  the  orbit  are  inserted  into  the  sclerotic 
about  \  inch  from  the  cornea,  or,  according  to  Fuchs,  the  internal  rectus 
5.5  mm.,  the  inferior  6.5  mm.,  the  external  6.9  mm.,  the  superior 
7.7  mm.  from  the  corneal  margin.  The  points  of  insertion  form  a  spiral 
which,  commencing  with  the  internal  rectus  and  ending  with  the  superior, 
gradually  reaches  farther  from  the  edge  of  the  cornea.  The  tendons  of 
the  internal  and  external  recti  are  often  divided  for  strabismus,  and  are 
reached  at  the  above  distances  from  the  corneal  margin  after  incising 
the  conjunctiva  and  the  capsule  of  Tenon.  The  tendons  are  then  hooked 
up  with  a  blunt  hook  and  divided  close  to  their  sclerotic  attachment. 
In  enucleation  of  the  globe  this  is  repeated  with  the  four  recti  and  the 
oblique  tendons  after  incising  the  conjunctiva  and  capsule  of  Tenon 
circularly  a  little  outside  of  the  margin  of  the  cornea.  The  optic  nerve 
is  then  divided  by  curved  scissors  from  the  outside  of  the  globe.  The 
latter  may  be  enucleated  without  opening  the  posterior  compartment 
of  the  orbit.    The  width  of  the  thin  flat  tendons  varies  from  7  to  9  mm. 

Muscular  Actions. — The  movements  of  the  globe  take  place  around 
three  principal  axes,  which  pass  through  its  centre.  The  eyeball  is  not 
altered  in  its  position  in  the  orbit,  but  the  cornea,  or  front  of  the  eye,  is 
moved  upward  or  outward,  etc.,  while  the  back  of  the  globe  moves  in 
the  opposite  direction  around  the  particular  axes  of  motion,  which  pass 
through  the  centre  of  the  globe.  If  the  anteroposterior  axis  of  the  orbit 
were  in  the  same  line  as  that  of  the  eyeball,  the  superior  and  inferior  recti 
would  simply  elevate  and  depress  the  eye,  for  their  line  of  action  is  in 
line  with  the  axis  of  the  orbit;  but  as  their  line  of  action  forms  an  angle 
with  the  anteroposterior  axis  of  the  globe,  and  passes  internal  to  its 
vertical  axis,  both  muscles  adduct  the  eye.  On  the  other  hand,  both  the 
superior  and  inferior  oblique  abduct  the  eye,  and  the  former  depresses,  the 
latter  elevates  it.  Hence  to  produce  simple  elevation  or  depression 
of  the  eye  the  superior  oblique  acts  with  the  inferior  rectus  and  the 
inferior  oblique  with  the  superior  rectus  to  counteract  the  adduction  of 
tin  recti  muscles.  Furthermore  the  inward  rotation  of  the  superior 
pectus  and  the  outward  rotation  of  the  inferior  rectus  are  counteracted 
by  tli''  opposite  movements  of  the  inferior  and  superior  oblique  muscles 
respectively.  The  external  and  internal  recti  produce  simple  abduction 
and  adduction  as  their  lines  of  action  are  parallel  with  the  horizontal 
plane  of  the  globe.  Abduction,  is  also  produced  by  both  oblique  muscles 
acting  together,  and  adduction  by  the  superior  and  inferior  recti  acting 
together.  In  case  of  weakness,  paralysis,  or  abnormal  length  of  one 
muscle,  (In-  opposing  muscle  overacts  ami  turns  the  eye  away  from  the 
ireaker  side  and  the  eye  cannot  be  moved  to  the  full  extent  if  ;if  .-ill  in  the 
opposite  direction,    Strabismus,  squint  or  cross-eye,  is  thus  produced.    If 


76  THE  HEAD  AND  NECK 

the  patient  tries  to  look  in  the  direction  of  the  affected  muscle  the  affected 
eye  fails  to  move,  so  that  the  eyes  are  directed  in  different  directions  and 
double  vision  results.  Double  vision  does  not  result  on  looking  toward 
the  side  to  which  the  affected  eye  is  kept  directed.  To  avoid  double 
vision  the  patient  turns  his  head  to  the  side  toward  which  the  affected 
muscle  cannot  move  the  eye,  so  that  the  muscle  is  not  called  upon  to  act. 
Thus  if  the  right  external  rectus  is  paralyzed,  the  right  eye  is  directed 
internally  and  the  patient  has  little  difficulty  in  looking  toward  the  left; 
but  if  he  tries  to  look  toward  the  right,  the  right  eye  fails  to  abduct  and 
remains  stationary.  Hence  the  head  is  kept  constantly  turned  toward 
the  right  to  allow  him  to  look  in  this  direction,  for  he  can  move  both  eyes 
in  the  opposite  direction. 

To  Detect  the  Muscular  Paralysis  by  Looking  at  the  Patient's  Face. — 
Ranney  has  given  the  rule  that  "The  head  is  so  deflected  that  the  chin 
is  carried  in  a  direction  corresponding  to  the  action  of  the  affected 
muscles."  One  affected  with  strabismus  is  often  able  to  educate  him- 
self to  disregard  one  visual  image,  which  would  give  rise  to  double 
vision,  and  to  use  the  other  eye  as  the  "working  eye."  This  is  espe- 
cially true  in  case  of  a  double  convergent  squint. 

The  superior  and  inferior  recti  are  supplied  by  the  same  nerve,  the 
third,  but  the  external  is  supplied  by  the  sixth  and  the  internal  by  the 
third  nerve.  Hence  strabismus  from  weakness  or  paralysis  of  one  of 
two  opposing  muscles  is  usually  an  internal  or  external  one,  as  either  the 
internal  or  external  rectus  is  more  likely  to  be  affected  without  the  other. 
There  may  be  another  reason  why  double  convergent  strabismus  is  a 
particularly  common  form.  For  in  that  congenital  defect  of  the  eye  in 
which  the  rays  are  naturally  focussed  behind  the  retina  (hypermetropia 
or  far-sightedness)  the  ciliary  muscle  struggles  to  accommodate  the  lens 
so  as  to  properly  focus  the  rays.  This  action  of  accommodation  is 
closely  associated  with  that  of  convergence  or  adduction,  for  the  third 
nerve  supplies  both  muscles,  so  that  a  certain  amount  of  the  energy 
employed  in  accommodation  passes  into  the  internal  recti  and  the  child 
gradually  acquires  a  convergent  squint. 

Nerves  of  the  Orbit. — The  fibers  of  the  optic  nerves  decussate  in  the 
optic  commissure,  so  that  the  inner  half  of  one  eye  may  work  in  harmony 
with  the  outer  half  of  the  other,  for  the  image  of  an  object  on  one  side 
of  the  main  axis  of  vision  is  received  on  the  opposite  (inner  and  outer) 
but  corresponding  side  (right  or  left)  of  both  eyes.  When,  therefore,  the 
optic  tract  of  one  side  is  paralyzed  by  pressure,  etc.,  the  outer  half 
of  the  retina  on  that  side  and  the  inner  half  of  the  retina  on  the 
opposite  side  are  blind,  and  objects  on  the  side  opposite  the  lesion 
cannot  be  seen  (hemianopsia).  The  optic  nerve  has  been  severed  by  a 
stab  wound  of  the  orbit  and  torn  across  or  pressed  upon  in  fractures  of 
the  orbit  or  of  the  small  wing  of  the  sphenoid.  The  optic  nerve  is  accom- 
panied through  the  posterior  half  of  the  orbit  by  an  investment  of  dura, 
arachnoid,  and  pia,  continued  from  the  cranial  cavity.  These  layers  are 
not  adherent  together,  but  leave  a  potential  space  between  them  as  in 
the  cranial  cavity.    In  this  respect  the  optic  differs  from  the  other  cranial 


THE  FACE  77 

nerves  from  the  third  to  the  twelfth.  Cases  of  sudden  blindness  without 
visible  changes  on  ophthalmoscopic  examination  are  to  be  explained  by 
a  hemorrhage  or  other  effusion  within  this  meningeal  sheath. 

The  third  nerve  (motor  oculi)  supplies  all  the  muscles  of  the  orbit 
except  the  external  rectus  and  the  superior  oblique,  and,  through  the 
lenticular  ganglion,  it  supplies  the  ciliary  muscle  and  the  sphincter 
fibers  of  the  iris.  Many  of  the  actions  of  the  third  nerve  are  seen  in 
viewing  near  objects.  Thus  both  eyeballs  are  directed  inward  by  the 
internal  recti  acting  in  unison,  for  which  purpose  the  third  nerves  of  the 
two  sides  are  associated  at  their  origin  in  the  gray  matter  around  the 
aqueduct  of  Sylvius.  The  pupil  is  also  contracted  by  its  sphincter 
fibers  to  cut  off  the  peripheral  rays,  and  the  lens  is  made  more  convex 
by  the  ciliary  muscle  to  focus  the  divergent  rays. 

When  the  third  nerve  is  completely  paralyzed  the  upper  eyelid  droops 
(ptosis)  from  paralysis  of  the  levator  palpebral,  there  is  a  divergent 
squint  with  double  vision  (diplopia)  from  the  unopposed  action  of  the 
external  recti,  the  pupil  is  dilated  and  cannot  be  contracted  on  account 
of  paralysis  of  the  circular  fibres  of  the  iris,  and  accommodation  for  near 
objects  is  lost  from  paralysis  of  the  ciliary  muscle.  Movement  of  the  globe 
in  a  direction  outward  and  downward  is  still  possible  by  means  of  the 
superior  oblique  and  the  external  rectus,  but  otherwise  the  eye  is  motion- 
less. The  globe  may  protrude  somewhat  from  the  relaxation  of  three  of 
the  recti  muscles.  In  partial  paralysis  these  symptoms  may  be  either 
partly  developed  or  only  one  or  two  may  be  present.  The  pupil  is  con- 
tracted not  only  in  viewing  near  objects  but  also  under  the  influence  of  a 
bright  light.  The  latter  contraction  is  reflex,  the  former  is  a  matter  of 
accommodation.  The  pupil  in  which  the. reflex  contraction  is  absent 
while  the  accommodation  contraction  is  present,  as  in  locomotor  ataxia, 
is  called  the  "Argyll-Robertson  pupil." 

In  paralysis  of  the  fourth  nerve,  which  supplies  the  superior  oblique 
only,  there  may  be  little  change  in  the  mobility  of  the  globe,  for  the 
function  of  this  muscle  may  be  performed  vicariously,  at  least  in  part. 
But  then-  will  be  diplopia  in  certain  positions  of  the  eye,  for  there  is 
deviation  of  the  eye  inward  on  lowering  the  object  viewed.  That  the 
muscles  of  the  two  sides  may  act  in  unison  the  fibers  of  the  two  nerves 
decussate  in  the  gray  matter  around  the  Sylvian  aqueduct. 

When  the  sixth  nerve  is  paralyzed  there  is  convergent  strabismus,  with 
consequent  diplopia,  owing  to  the  paralysis  of  the  external  rectus,  which 
glone  it  supplies,  and  the  unopposed  action  of  the  internal  rectus.  As 
the  patient  is  unable  to  rotate  the  eve  directly  outward,  the  head  is  turned 
outward  instead.  The  fibers  of  the  two  sixth  nerves  do  not  decussate 
at  their  origin,  as  the  two  external  recti  do  not  need  to  act  in  concert. 
The  nucleus  of  the  sixth  nerve  is  connected  with  that  of  the  third  nerve 
of  the  opposite  side  by  fibers  which  pass  eventually  into  the  internal 
rectus,  so  that  both  eyes  ran  be  directed  to  the  right  or  left  by  the  action 
of  ;i  single  nucleus. 

Paralysis  of  all  the  oculomotor  nerves  indicates  a  lesion  which  is 
probably  at  their  central  origin  or  at  the  cavernous  sinus,  in  the  wall  of 
which  they  lie  ne;ir  together. 


78  THE  HEAD  AND  NECK 

When  the  ophthalmic  division  of  the  fifth  nerve  is  paralyzed  there  is 
anesthesia  of  the  globe,  conjunctiva,  upper  eyelids,  and  other  parts 
supplied.  Under  these  conditions  the  conjunctiva  and  cornea,  especially 
the  latter,  are  apt  to  be  the  seat  of  ulceration.1  Hence  after  removal 
of  the  Gasserian  ganglion  for  trigeminal  neuralgia  the  eye  has  to  be 
carefully  protected  or  altogether  closed. 

The  supra-orbital  branch  of  this  nerve,  which  supplies  the  scalp  nearly  as 
far  back  as  the  lambdoid  suture,  is  not  infrequently  the  seat  of  neuralgia. 
When  it  demands  operative  treatment  it  may  be  readily  exposed  by  a 
horizontal  incision  centring  at  the  junction  of  the  middle  and  inner 
thirds  of  the  supra-orbital  margin,  where  the  notch  if  present  can  be  felt. 
Continued  pressure  on  the  nerve  at  this  point  may  be  used  to  detect  a 
person  shamming  insensibility  or  to  rouse  a  person  from  alcoholic  coma. 
No  malingerer  can  bear  the  pressure  for  long. 

The  effects  on  the  eye  of  a  paralysis  of  the  sympathetic  fibers,  which 
reach  it  along  the  internal  carotid  from  the  cervical  sympathetic,  are 
as  follows:  There  is  some  drooping  of  the  upper  lid  from  a  paralysis 
of  the  unstriped  muscle  fibers  (superior  palpebral  muscle  of  Muller) 
which  extends  from  the  under  surface  of  the  levator  palpebrse  muscle 
to  the  upper  margin  of  the  tarsal  cartilage.  There  is  some  recession 
of  the  globe,  which  is  explained  by  some  as  due  to  the  paralysis  of  smooth 
muscle  fibers  bridging  over  the  sphenomaxillary  fissure,  the  orbitalis 
muscle  of  Muller.  The  removal  of  the  cervical  sympathetic  ganglia, 
advised  and  practised  for  the  treatment  of  exophthalmic  goitre,  may, 
therefore,  improve  the  exophthalmos  in  this  way.  The  pupil  is  also 
narrowed  and  loses  its  power  of  dilatation  by  the  paralysis  of  the  radi- 
ating dilator  fibers  of  the  iris.  Of  these  several  symptoms  only  the  ptosis 
is  permanent.  The  caliber  of  the  blood  vessels  of  the  orbit  has  not  been 
observed  to  change  in  paralysis  of  the  cervical  sympathetic. 

Damage  to  the  orbital  nerves  may  be  due  to  fractures  of  the  orbit  or 
the  base  of  the  skull,  wounds  of  the  orbit,  and  the  pressure  of  tumors, 
aneurysms,  and  bloody  or  inflammatory  effusions  along  their  course  or 
at  their  origin.  The  sixth  nerve  is  more  liable  to  be  injured  in  fractures 
of  the  base  of  the  skull  on  account  of  its  more  intimate  connection  with  it. 

Vessels  of  the  Orbit. — The  arteries  are  small  and  seldom  give  trouble 
when  divided  in  enucleation  of  the  globe,  for  they  can  be  readily  com- 
pressed against  the  bony  wall.  The  ethmoidal  arteries  may  be  torn  in  a 
fracture  of  the  anterior  cranial  fossa.  Pulsating  tumors  of  the  orbit 
may  be  due  to  a  traumatic  aneurysm  of  an  orbital  artery,  to  an  arterio- 
venous aneurysm  between  the  internal  carotid  artery  and  the  cavernous 
sinus,  or  to  pressure  upon  the  ophthalmic  vein  by  an  aneurysm  of  the 
internal  carotid.  In  these  pulsating  tumors  the  eye  is  also  protruded. 
Pressure  upon  the  ophthalmic  vein,  or  the  cavernous  sinus  into  which  it 

1  This  is  due  partly  to  the  paralysis  of  the  trophic  nerve  fibers  contained  in  the  nerve;  partly  to 
the  anesthesia  which  allows  the  parts  to  be  readily  injured,  as  there  is  no  sensation  and  the  reflex 
winking,  due  to  irritation  of  the  conjunctiva,  is  wanting;  and  partly  to  the  loss  of  the  reflex  of 
the  sensory  nerves  upon  the  caliber  of  the  bloodvessels,  so  that  the  progress  of  inflammation  is 
unopposed. 


THE  NOSE,  NASAL  FOSSAE  AND  ACCESSORY  SINUSES         79 

empties,  by  a  tumor  or  an  inflammatory  deposit,  etc.,  causes  a  venous 
congestion  of  the  tributaries  of  the  vein.  This  congestion  is  visible 
i hr<  »ugh  the  ophthalmoscope  as  a  "  choked  disk."  The  presence  of  such  a 
condition  may  assist  in  the  diagnosis  of  a  supposed  tumor  of  the  brain 
or  an  exudate  at  the  base  of  the  brain.  As  the  facial  vein,  through  the 
angular,  cormnunicates  freely  with  the  ophthalmic,  and  there  are  no 
valves  in  these  veins,  the  venous  congestion  in  the  latter  vein  may  be 
relieved  through  the  former,  if  the  condition  has  come  on  slowly.  This 
same  free  communication  renders  serious  any  septic  condition  of  the 
face  in  the  neighborhood  of  the  facial  vein  (carbuncle,  erysipelas,  etc.), 
on  account  of  the  danger  of  the  infection  extending  along  the  veins  to 
the  cavernous  sinus  and  setting  up  a  septic  sinus  thrombosis. 

The  amount  of  fat  (Fig.  25)  behind  Tenon's  capsule,  which  embeds 
the  other  structures  of  the  orbit,  is  partly  responsible  for  the  varying 
prominence  of  the  eyeball  in  different  persons  or  in  the  same  person  at 
different  times.  The  absorption  of  this  fat  in  cases  of  wasting  disease 
or  prolonged  illness  causes  the  sunken  eye  characteristic  of  such  con- 
ditions. This  loose  fat  allows  the  ready  spread  of  orbital  abscess  which 
may  follow  injuries  or  inflammations  of  the  orbit,  the  globe  or  adjacent 
parts.  The  pus  may  occupy  the  entire  posterior  compartment  of  the 
orbit  (i.  e.,  behind  the  capsule  of  Tenon)  and  displace  the  eyeball  for- 
ward, limiting  its  movements.  The  pressure  on  the  vessels  interferes 
with  the  venous  circulation  and  causes  great  redness  of  the  conjunctiva 
and  swelling  of  the  lids.  A  similar  effect  may  be  produced  by  emphy- 
sema of  this  fatty  tissue,  which  may  result  from  fracture  of  the  inner 
wall  of  the  orbit  involving  the  nasal  fossa  and  which  is  increased  on  blow- 
ing the  nose.  This  fat  also  furnishes  a  favorable  site  for  the  growth  of 
tumors  and  the  lodgement  of  foreign  bodies.  Some  of  the  latter  are  of 
remarkable  size  and  shape,  and  they  have  sometimes  remained  for  long 
periods  of  time  without  causing  much  trouble.  For  example,  a  case  is 
described  by  Lawson  where  an  iron  hat  peg  three  inches  long  lodged  in 
the  orbit  for  several  days  without  the  patient  knowing  it.  In  other  cases 
suppuration  takes  place  and  nature  gets  rid  of  the  foreign  body  through 
the  opening  or  incision  of  the  abscess.  In  a  remarkable  case  of  this  kind, 
described  by  Furneaux  Jordan,  a  man,  several  weeks  after  threshing 
wheat,  ejected  from  a  bed  of  pus,  by  pressure  on  the  lower  lid,  a  sprouting 
grain  of  wheat  which  I iad  set  up  a  severe  ophthalmia. 


THE  NOSE,  NASAL  FOSS.E  AND  ACCESSORY  SINUSES. 

The  External  Nose. — The  external  nose  is  largely  for  cosmetic  pur- 

.  a  facl  strikingly  illustrated  by  the  hideous  appearance  of  those 

with  marked  nasal  deformity.    The  nasal  cavities  serve   the  functions  of 

olfaction  and  respiration  (filtering,  warming  and  moistening  the  air),  and 

in  the  taste  and  voice. 

The  groove  between  the  nose  and  the  cheek  is  a  favorable  site  for 
incisions,  as  in  excision  of  the  maxilla,  for  the  resulting  scar  is  scarcely 


80  THE  HEAD  AND  NECK 

perceptible.  From  without  inward  we  find  the  following  layers  com- 
posing the  nose. 

1.  The  Skin.— The  skin  is  thin  and  loosely  adherent  over  the  bony 
portion  of  the  nose,  thick  and  closely  adherent  in  the  cartilaginous  part. 
Hence  in  plastic  operations  the  skin  readily  lends  itself  to  the  formation 
of  flaps  in  the  former  situation,  but  not  in  the  latter.  The  skin  is  very 
vascular,  so  that  wounds  and  plastic  operations  heal  well.  This  vas- 
cularity explains  the  readiness  of  the  nose  to  assume  a  rosy  color  from 
the  dilating  effect  on  the  vessels  of  heat,  cold,  alcohol,  etc.  In  alco- 
holics, in  those  exposed  to  the  weather,  and  in  some  chronic  dyspeptics 
the  superficial  vessels  become  permanently  dilated.  The  skin  of  the  lower 
part  of  the  nose  is  furthermore  very  richly  supplied  with  sudoriferous 
and  sebaceous  glands,  so  that  it  is  a  favorite  site  for  acne.  The  hyper- 
trophic form  of  acne,  known  in  this  situation  as  "grog  blossom,"  may 
produce  a  red  tuberous  enlargement  of  considerable  size.  From  an 
experience  of  several  cases  I  have  found  that  this  disfigurement  may  be 
satisfactorily  treated  by  shaving  down  and  shaping  the  nose,  taking  care 
not  to  cut  through  the  mucous  membrane,  and  then  skin  grafting  the 
surface  or  allowing  it  to  cicatrize.  Lupus,  lupus  erythematosus,  and 
epithelioma,  or  rodent  ulcer,  are  frequently  met  with  here,  the  latter  espe- 
cially in  the  alar  sulcus.  Plastic  operations  for  epithelioma,  or  removal 
followed  by  skin  grafting,  give  excellent  results.  Notwithstanding  the 
abundant  blood  supply,  the  nose,  like  the  ear,  is  prone  to  frostbite  on 
account  of  its  exposed  situation  and  the  superficial  position  of  the  vessels, 
the  circulation  of  which  at  the  edge  of  the  nostril  is  terminal.  The  vas- 
cularity of  the  lower  part  of  the  nose  favors  congestion,  which  partly 
accounts  for  the  pain  in  inflammation  here;  for,  owing  to  the  density 
of  the  closely  united  skin  and  subcutaneous  tissue,  the  swelling  due  to 
congestion  necessitates  pressure  upon  the  nerves.  These  nerves  are 
branches  of  the  first  or  second  divisions  of  the  fifth  nerve. 

The  next  layer,  (2)  the  subcutaneous  tissue,  has  already  been  referred 
to.  It  is  loose  above,  dense  below.  The  subjacent  or  fibromuscular 
layer  (3)  requires  no  special  notice.  (4)  The  osteocartilaginous  layer 
forms  the  framework  of  the  nose.  This  is  also  supported  fcfy  the  osteo- 
cartilaginous nasal  septum,  the  loss  of  substance  of  which,  especially 
in  its  cartilaginous  portion,  may  affect  the  shape  of  the  nose. 

The  movability  of  the  lower  or  cartilaginous  part  of  the  nose  obvi- 
ates many  fractures.  The  latter  are  most  common  through  the  lower 
most  prominent  and  thinnest  third  of  the  nasal  bones.  In  the  upper 
third  fracture  is  most  rare  on  account  of  the  thickness  and  firm  support 
of  the  bones,  but  it  is  here  most  serious,  for  it  requires  considerable 
force,  which  is  liable  to  be  communicated  to  the  vertical  and  cribriform 
plates  of  the  ethmoid  and  thus  cause  an  indirect  fracture  of  the  base  of 
the  skull.  The  displacement  of  bony  fragments  in  a  fracture  of  the  nose 
is  due  solely  to  the  direction  of  the  force,  and  should  be  reduced  by  ele- 
vation from  within  the  nasal  cavity,  as  by  the  beak  of  a  small  steel  sound, 
combined  with  manipulation  from  without.  Otherwise  deformity  results. 
Union  of  the  fragments  has  been  observed  as  early  as  the  seventh  day 


THE  XOSE,  NASAL  FOSSAE  AND  ACCESSORY  SINUSES         gl 

(Hamilton),  and  it  occurs  more  rapidly  than  with  any  other  fracture. 
As  (5)  the  mucosa  is  intimately  adherent  to  the  bone,  it  is  almost  always 
torn  through  in  a  fracture  rendering  the  latter  compound,  so  that  epistaxis 
is  the  rule,  and  subcutaneous  emphysema  is  likely  to  occur  and  to  be 
increased  on  blowing  the  nose.  We  not  infrequently  see  marked  depres- 
sion of  the  bony  portion  or  bridge  of  the  nose,  "saddle  nose."  This 
depends  not  so  often  upon  a  fracture  as  upon  imperfect  development 
from  malnutrition  in  those  with  inherited  syphilis.  The  cartilaginous 
part  may  also  be  destroyed  by  the  ulceration  of  lupus,  syphilis,  or 
epithelioma. 

The  various  deformities  of  the  nose,  on  account  of  the  hideous  dis- 
figurement often  produced,  have  led  to  numerous  plastic  operations 
(rhinoplasty).  Some  of  these  were  practised  centuries  ago.  Partial 
rhinoplasty  often  gives  excellent  results.  A  depressed  bridge  of  the  nose 
may  be  improved  by  the  introduction  beneath  theTskin  of  an  aseptic 
substance  to  fill  out  the  depression.  The  difficulty  in  total  rhinoplasty 
is  that  a  nose  made  of  soft  parts  has  no  firm  support  and  is  liable  to 
contraction.  For  this  reason  the  Indian  method,  by  which  the  new 
nose  is  made  of  a  flap  from  the  forehead,  the  pedicle  of  which  receives  the 
frontal  branch  of  the  ophthalmic  artery,  has  been  modified  to  include 
in  the  flap  the  outer  table  of  bone,  and  the  flap  is  not  twisted  as  in  the 
Indian  method,  but  inverted,  and  its  raw  outer  surface  covered  by  skin 
flaps  from  the  sides.  In  cases  where  there  is  an  actual  loss  of  the  nose 
and  not  a  mere  deformity  the  operation  is  advisable. 

The  limits  of  the  cartilaginous  part  should  be  remembered,  for  in 
introducing  and  opening  a  nasal  speculum  the  latter  should  not  be 
passed  beyond  those  limits,  otherwise  pain  results.  The  lower  of  the 
two  pairs  of  cartilages  of  the  nose  are  curved  around  in  front  of  the 
nostril,  whose  contour  they  form.  The  mesial  interval  between  their 
internal  branches  can  be  felt  at  the  tip  of  the  nose,  and  into  it  projects 
the  septal  cartilage.  The  latter  can,  therefore,  be  reached  and  resected 
by  a  median  incision  between  the  lateral  cartilages  without  opening 
the  nasal  cavities. 

Several  operations  are  performed  on  the  nose  to  expose  the  nasal  fossa; 
or  even  the  nasopharynx  behind.  In  Rouge's  operation  the  incision  is 
made  through  the  mucous  membrane,  where  it  is  reflected  from  the  gums 
to  the  upper  lip,  between  the  second  bicuspids  of  both  sides.  Then  the 
soft  parts  which  connect  the  upper  lip  and  nose  to  the  bone  are  divided 
and  the  lip  turned  well  up,  exposing  the  anterior  part  of  the  nasal  fossae. 
These  may  be  more  fully  exposed  by  turning  up  the  movable  portion  of 
the  aose  by  separating  die  alar  cartilage  from  the  bone  and  dividing  the 
septal  cartilage.     No  visible  scar  is  left.    <  >r  the  nose  may  be  turned 

down  after  inciting  the  soft,  parts  in  the  groove  on  either  side  of  it  and 
across  its  root  and  dividing  the  bone  in  the  Mime  line. 

The  suture  between  the  nasal  and  frontal  bones  at  the  pool  of  the  nose 

is  a  favorite  place  for  meningoceles,  etc.    They  have  been  mistaken  for 

being  often  covered  by  a  thin  vascular  skin.     In  rare  Instances 

•  cape  through  the  cribriform  plate  into  the  nasal  fossa?,  and  being 

8 


82  THE  HEAD  AND  NECK 

mistaken  and  treated  for  a  polypus,  the  cribriform  plate  has  been  injured 
and  fatal  meningitis  resulted. 

The  nasal  fossae  open  in  front  by  the  nostrils  and  communicate  behind 
with  the  nasopharynx  through  the  posterior  nares.  The  nostrils  or 
anterior  nares  look  downward  and  are  at  a  somewhat  lower  level  than 
the  floor  of  the  nasal  fossae.  Hence  in  examining  the  fossae  through 
a  speculum  the  tip  of  the  nose  is  raised  and  the  head  is  thrown  back. 
In  this  manner  the  floor  of  the  nose,  the  lower  part  of  the  septum,  the 
greater  part  of  the  inferior  turbinate  bone,  and  the  lower  margin  of  the 
middle  turbinate  may  be  seen,  with  a  good  light.  The  nostrils  are 
separated  by  the  columna,  composed  of  skin  and  fibrous  tissue,  which 
extends  below  the  septal  cartilage,  and  the  latter  may  be  reached  by 
splitting  the  columna  mesially. 

The  anterior  nasal  orifice  is  the  heart-shaped  anterior  or  facial  aper- 
ture of  the  bony  nasal  fossse,  measuring  3  cm.  (1£  in.)  vertically  and  a  little 
less  transversely  in  its  widest  part.  It  can  be  palpated  by  the  finger 
introduced  through  the  nostril.  The  portion  of  each  nasal  fossa  between 
the  anterior  nasal  orifice  and  the  nostrils  is  called  the  vestibule,  and 
differs  from  the  rest  of  the  fossa  in  being  covered  by  the  cartilaginous 
part  of  the  nose  and  in  being  lined  by  a  squamous  epithelium,  a  con- 
tinuation of  the  skin.  This  is  beset  near  the  nostrils  with  stiff  hairs 
(vibrissse)  which  serve  to  filter  the  air  and  arrest  particles  of  dsut.  It  is 
also  provided  with  sebaceous  glands  and  is  liable  to  eczema  and  to  painful 
furuncles  originating  in  the  glands,  etc. 

The  posterior  nares  are  symmetrically  placed  on  either  side  of  the 
posterior  border  of  the  nasal  septum,  which  forms  their  mesial  boundary. 
They  measure  2.5  to  3  cm.  (1  to  1|  in.)  vertically  and  12  mm.  (£  in.)  trans- 
versely in  the  skeleton,  but  these  measurements  are  reduced  somewhat 
by  the  covering  of  mucosa  and,  in  the  upper  and  outer  aspects,  by  the 
projection  of  the  Eustachian  tube.  They  maybe  seen  with  difficulty  by 
posterior  rhinoscopy,  in  which  a  small  mirror  is  introduced  behind  the 
soft  palate.  Through  this  can  be  seen,  under  favorable  circumstances, 
the  posterior  part  of  the  septum,  and  of  the  turbinate  bones  and  meati 
(especially  the  middle  and  inferior),  also  the  openings  of  the  Eustachian 
tubes  and  the  roof  of  the  pharynx.  The  same  parts  may  be  felt  by  the 
finger  introduced  through  the  mouth  and  above  the  soft  palate.  The 
posterior  nares  are  sometimes  plugged  to  arrest  bleeding  from  the  nose. 
For  this  purpose  a  pyramidal  plug  of  several  folds  of  gauze  is  made 
whose  base  measures  a  little  more  than  the  posterior  nares.  This  is 
threaded  with  two  ligatures  from  the  apex  and  one  from  the  base  and 
pulled  up  into  place  from  behind  by  means  of  a  cord  which  has  been 
passed  through  the  inferior  meatus  into  the  pharynx  and  out  through 
the  mouth  by  a  Bellocq's  sound  or  a  soft  catheter.  The  two  cords  pass 
out  through  the  nostril  and  are  there  tied  tightly  over  a  plug  in  the 
nostril,  thereby  plugging  the  latter  and  holding  the  posterior  plug 
snugly  in  place.  The  single  cord  from  the  base  of  the  plug  is  passed 
out  through  the  mouth  to  be  used  in  withdrawing  the  plug.  The  same 
object  may  usually  be  more  easily  accomplished  by  inserting  a  strip  of 
gauze  through  the  nostril  and  packing  it  well  into  the  nasal  fossse. 


PLATE   III 


FIG.  2  7 


IN  FRAORBITAL 

NERVE 


INTERNAL 
MAXILLARY 
ARTERY 


DESCEN  DING 

PALATINE 

ARTERY 


O-PALATINE 
RTERY 


Transverse  Vertical  Section  of  the  Nasal   Fossae.    (Zuckerkandl. ) 

Viewed  from  in  front,  showing  the  back  of  the  right  orbit  an  1  the  ri^l'i  antrum  of 
Highmore,  with  the  sphenomaxillary  fossa  behind  the  latter,  exposed  through  an  opening 
nf  it-  posterior  wall. 


THE  NOSE,  NASAL  FOSS&  AND  ACCESSORY  SINUSES  83 

The  Nasal  Fossae  (Fig.  27). — The  nasal  fossa?  lie  beneath  the  cranium, 
above  the  mouth,  and  between  the  orbits  and  maxillary  sinuses.  They 
are  very  narrow  above,  but  widen  out  somewhat  below,  so  that  while  there 
intervenes  a  space  of  4  to  5  mm.  between  the  inferior  turbinate  bone  and 
the  septum,  only  2  mm.  intervenes  between  the  latter  and  the  superior 
turbinate  bone.  In  fact,  the  latter  space  is  so  narrow  that  surgically  the 
superior  turbinate  bone  practically  forms  the  roof  of  the  nasal  fossae. 
Owing  to  the  narrowness  of  the  fossae,  polypus  or  other  forceps  are  best 
introduced  so  as  to  be  opened  vertically. 

The  floor  is  the  widest  part  of  the  nasal  fossae,  and  measures  at  its 
centre,  or  widest  part,  12  to  15  mm.  (£  to  f  in.)  in  width.  It  is  smooth, 
concave  transversely,  and  slanted  slightly  downward  behind,  so  that  in 
the  erect  position  secretions  drain  backward  to  the  pharynx. 

The  roof  is  extremely  narrow,  2  to  3  mm.  (T\  to  ^  in.),  so  that  surgical 
exploration  or  operation  here  is  nearly  out  of  the  question,  and  there  is 
little  danger  of  its  penetration  by  anything  as  large  as  a  polypus  forceps. 
Yet  it  has  been  perforated  by  slender  bodies,  by  accident  or  design,  and 
the  cranial  cavity  thereby  opened  through  the  cribriform  plate.  In  such 
cases,  or  in  fracture  of  this  plate  involving  the  mucosa  beneath  it,  there 
is  bleeding  from  the  nose,  the  discharge  of  cerebrospinal  fluid,  if  the  sub- 
arachnoid space  is  opened,  and  the  danger  of  meningitis,  as  it  is  impos- 
sible to  make  and  keep  the  nose  aseptic.  In  fact,  meningitis  has  resulted 
from  the  extension  of  inflammation  through  an  intact  nasal  roof  in  case 
of  inflammation  of  the  nose.  In  front  of  the  cribriform  plate  the  roof 
slants  downward.  It  is  here  formed  by  the  nasal  bones  and  the  nasal 
spine  of  the  frontal,  and  above  the  latter  lie  the  frontal  sinuses.  Behind 
the  cribriform  plate  the  roof  slants  more  abruptly  downward,  and  is 
formed  by  the  anterior  surface  of  the  sphenoid  containing  the  openings 
of  the  sphenoidal  sinuses.  It  follows  that  the  height  of  the  fossae  is 
greatest  about  their  centres. 

The  median  wall  or  septum  is  straight  in  children  up  to  the  seventh 
year  and  in  aborigenes;  but  in  adults  it  deviates  to  one  side  in  over 
75  per  cent.,  usually  to  the  left,  but  according  to  many  to  the  right. 
A  deviation  may  follow  an  injury,  but  this  is  not  the  common  cause.  It 
probably  depends  upon  the  faulty  development  of  the  superior  dental 
arch,  especially  its  premaxillary  portion,  so  that  the  septum  grows  more 
rapidly  than  the  space  for  it  enlarges.  It  is  attributed  to  the  continued 
growth  of  the  septal  bones  in  the  vertical  plane  after  they  have  united 
;it  their  edges.  The  QOSe,  as  a  whole,  is  seldom  absolutely  straight,  and 
this  has  been  attributed  to  blowing  the  nose  with  the  same  hand,  usually 

tin-  right,  sleeping  largely  on  the  righl  side,  etc.  The  septal  deviation 
may  involve  the  bony  (53  per  cent.,  Zuckerkandl)  or  the  cartilaginous 
portions  alone,  or  bom.  It  most  often  occurs  at.  the  junction  of  the  eth- 
moid and  vomer,  or  ;il  thai  of   die  latter  with    the  septal  cartilage,  and  it' 

it  i^  marked  it  may  more  or  less  block  one  nasal  fossa  by  contact  with 

the    turbinate    bones.      This    contact    is    a  source  of  constant   irritation, 

and  may  result  in   fusion  of  the  parts  (synechia).     Until  we  examine 

the  opposite  fossa  and   note  the  concavity  of  the  septum  we  may  mis- 


84 


THE  HEAD  AND  NECK 


take  the  deviation  of  the  septum  for  a  septal  tumor,  abscess,  or  hema- 
tocele, or  even  a  nasal  polyp.  There-  are  many  operations  for  the 
restoration  of  the  blocked  fossa  or  the  straightening  of  the  septum. 
Exostoses  or  "spurs"  are  liable  to  grow  on  the  septum,  especially  at  the 
junction  of  the  bony  and  cartilaginous  portions.  As  the  septal  carti- 
lage is  the  principal  support  of  the  cartilaginous  part  of  the  nose,  its 
destruction  by  syphilis  causes  great  flattening  of  it.  Syphilitic  destruction 
of  the  bony  and  cartilaginous  septa  and  of  the  adjacent  bones  may  result 
in  the  flattening  of  the  bony  vault  also. 

The  mucosa  covering  the  septum  is  blended  with  its  periosteal  and 
perichondral  covering  into  a  single  dense  layer,  and  the  layer  thus  formed 
is  loosely  attached  to  and  easily  separated  from  the  septum.     Hence 


Fig.  28 


PROBE     P/,s 
SINUS   THflQ^O 


OPENINGS    OF    POSTERIOR 


ENOIDAL 
US 


External  wall  of  right  nasal  fossa,  parts  of  the  turbinates  having  been  cut  away  to  show  the 
orifices  of  the  sinuses  which  open  into  the  meatuses.      (Gerrish,  after  Testut.) 

collections  of  blood  or  pus  may  readily  form  beneath  the  mucoperiosteal 
covering;  also  by  stripping  up  the  latter  the  septum  may  be  exposed  and 
operated  upon  without  entering  the  nasal  cavity. 

The  Outer  Wall  (Fig.  28).— The  outer  wall  has  a  general  slant  from 
above  downward  and  outward.  The  anterior  end  of  the  inferior  tur- 
binate bone  reaches  to  the  anterior  limit  of  the  bony  outer  wall  and  within 
about  2  cm.  (-§-  in.)  of  the  nostril.  The  posterior  end  of  this  bone  is  at  the 
posterior  nares,  on  a  level  with  the  opening  of  the  Eustachian  tube. 
The  free  border  of  the  inferior  turbinate  bone  may  extend  so  far  toward 
the  floor  of  the  nasal  fossa  as  to  interfere  with  the  introduction  of  instru- 
ments along  the  inferior  meatus.    The  latter  is  the  widest  part  of  the  nasal 


THE  NOSE,  NASAL  FOSSAE  AND  ACCESSORY  SINUSES  85 

fossae,  measuring  about  12  mm.  (h  in.).  Its  greatest  height  18  mm. 
(f  in.)  corresponds  to  the  opening  of  the  nasal  duct,  which  is  about  2.5  to 
3  cm.  (1  to  li  in.)  behind  the  nostril  (seepage  72).  The  sharp  down- 
ward slant  of  the  anterior  fourth  of  the  inferior  turbinate  bone  renders 
the  height  of  the  inferior  meatus  but  little  in  front  and  less  here  than  it  is 
behind.  Hence  inspired  air  is  not  so  apt  to  enter  this  meatus,  expired 
air  more  apt  to.  This  tendency  is  increased  by  the  downward  direction 
of  the  nostrils,  the  consequent  upward  current  of  inspired  air,  the  wide 
funnel-shaped  anterior  end  of  the  middle  meatus  (the  atrium),  and  the 
narrowed  posterior  end  of  this  meatus.  This  explains  the  fact  that  we 
smell  inspired  air,  for  it  passes  through  a  meatus  (middle), part  of  whose 
walls  is  supplied  by  the  olfactory  nerves,  as  well  as  the  fact  that  we  do  not 
smell  expired  air,  for  it  passes  largely  through  the  inferior  meatus,  which 
the  olfactory  nerves  do  not  reach.  Also,  if  we  wish  to  smell  an  object  we 
dilate  the  nostrils  and  sniff  up  the  air,  which  thereby  is  carried  into  the 
upper  or  olfactory  part  of  the  fossae.  On  the  other  hand,  discharge  in 
the  middle  meatus  or  upper  part  of  the  vestibule  cannot  be  so  readily 
removed  by  blowing  the  nose,  for  the  expired  air  passes  below  it. 

The  anterior  end  of  the  middle  turbinate  bone  inclines  upward  so  that 
it  reaches  the  level  of  the  inner  canthus  of  the  eye.  This  upward  inclina- 
tion makes  the  middle  meatus  open  up  widely  in  front  into  the  atrium, 
into  which  an  instrument,  introduced  through  the  nostril,  passes  more 
readily  than  into  the  inferior  meatus,  unless  care  is  taken.  About  the 
centre  of  the  middle  meatus  is  the  slit-like  opening  of  the  antrum,  about 
2.5  cm.  (1  in.)  above  the  floor  of  the  nasal  fossa  and  nearer  the  roof  than 
the  floor  of  the  antrum.  This  opening  is  at  the  lower  end  of  a  deep  groove, 
the  infundibulum,  which  curves  downward  and  backward,  overhung  by 
the  anterior  half  of  the  middle  turbinate.  In  about  half  the  cases  its 
upper  end  receives  the  canal  leading  from  the  frontal  sinus  (ostium 
frontale);  in  the  other  half  of  the  cases  the  infundibulum  ends  blindly. 
Into  this  groove  open  also  the  anterior  ethmoid  cells. 

The  Mucous  Membrane. — The  mucous  membrane  varies  in  dif- 
ferent parts  of  the  nasal  fossae.  Behind  the  vestibule  each  nasal  fossa  is 
divided  into  an  upper  olfactory  region,  including  the  middle  and  upper 
turbinate  bones  and  the  upper  third  of  the  septum,  which  is  covered  by 
columnar  epithelium,  and  a  lower  respiratory  region,  including  the  rest  of 
the  fossa,  which  is  covered  by  columnar,  ciliated  epithelium.  On  the 
outer  wall  between  the  turbinate  bones  and  on  the  floor  the  mucosa  is 
thin,  elsewhere  it  is  thick  and  vascular,  especially  over  the  turbinate 
bones.  This  thickness  over  the  turbinates  is  largely  due  to  the  abundant 
submucous  venous  plexus,  the  meshes  of  which  run  mostly  anteropos- 
teriorly.    The  mucous  membrane  extends  in  a  fold  beyond  the  inferior 

turbinate  bone  in  front,  behind,  and  below.  Over  tins  bone  the  veins 
of  the  thick   mucosa  form   ;i    kind  of  cavernous  or  erectile  /issue.     This 

■veil  up  rapidly  from  engorgement  of  the  veins  so  as  to  conn;  in 
contact  with  the  septum,  and  this  contact  is  in  itself  a  source  of  irritation. 
The  rapid  shrinkage  of  this  "erectile  body"  when  ;i  caustic  or  astringent 
i  applied  to  it  i-  very  striking. 


86  THE  HEAD  AND  NECK 

The  acinous  glands  of  the  mucosa,  secreting  for  the  most  part  a  thin 
watery  fluid,  are  most  numerous  over  the  inferior  turbinate  bone  and  the 
middle  and  posterior  parts  of  the  fossae.  They  account  for  the  profuse 
secretion  in  coryza.  The  normal  function  of  this  secretion  appears  to  be 
to  moisten  the  inspired  air  and  to  aid  the  cilia  in  the  removal  of  the  dust 
and  microorganisms  filtered  from  the  air.  The  chief  function  of  the  great 
vascularity  of  the  mucosa  is  to  warm  the  inspired  air.  Adenoid  tissue  is 
abundant  in  the  mucosa  of  the  posterior  part,  and  is  continuous  with  that 
of  the  nasopharynx.  Several  of  the  openings  found  in  the  bony  fossse 
are  closed  by  the  mucosa,  and  others  may  be  temporarily  closed  by  the 
swelling  of  this  membrane.  From  the  relations  of  the  nasal  fossae  and 
the  continuity  of  its  mucosa  with  that  of  other  parts  it  follows  that  inflam- 
mation of  this  mucosa  (coryza)  may  spread  through  the  posterior  nares 
to  the  pharynx  and  to  the  Eustachian  tubes,  through  the  nasal  duct  to 
the  lacrymal  sac  and  conjunctiva  and  through  the  infundibulum  to 
the  frontal  and  maxillary  sinuses  and  the  ethmoid  cells.  One  or  more  of 
these  extensions  is  often  exemplified  in  a  coryza. 

Swollen  turbinate  bones  may  be  mistaken  for  mucous  polypi  which 
are  common  in  the  nose  and  usually  arise  from  the  inferior  or  middle 
turbinate  bones.  They  often  grow  in  crops,  block  the  fossae,  and  may 
press  upon  and  widen  the  nose  or  obstruct  the  openings  on  its  outer  wall 
They  may  be  removed  with  the  snare  or  polypus  forceps,  care  being 
taken  not  to  damage  the  cribriform  plate  in  case  of  high  attachment. 
The  fibrous  and  sarcomatous  polypi  take  origin,  as  a  rule,  from  the  peri- 
osteum of  the  roof  of  the  nose  or  pharynx  and  spread  in  all  directions. 

The  Blood  Supply. — The  blood  supply  of  the  nose  is  derived  from  three 
sources,  the  ophthalmic,  facial,  and  internal  maxillary.  The  veins,  in 
addition  to  accompanying  the  arteries,  communicate  with  the  superior 
longitudinal  sinus  through  the  foramen  caecum  in  children  and  some- 
times in  adults.  This  communication  and  that  with  the  cavernous 
sinus  through  the  ophthalmic  veins  help  to  explain  intracranial  compli- 
cations in  some  cases  of  inflammation  of  the  nasal  cavities. 

Bleeding  from  the  nose,  or  epistaxis,  may  be  due  to  fracture  or  other 
injury,  general  oozing  of  the  vascular  mucosa,  ulceration  or  venous  con- 
gestion, as  in  cardiac  or  pulmonary  disease,  or  cerebral  congestion.  When 
due  to  congestion  the  patient  should  be  kept  erect  to  aid  venous  return, 
and  the  raising  of  the  arms  is  recommended  on  account  of  the  resulting 
expansion  of  the  thorax  and  its  aspiration  upon  the  cervical  veins.  In 
some  cases  the  bleeding  is  vicarious.  The  ulcerations  are  apt  to  be  on 
the  septum,  where  they  should  be  sought  for.  Nose  bleed  may  be  profuse 
and  long  continued;  as  much  as  75  pounds  of  blood  has  been  lost  alto- 
gether (Frank el),  and  it  has  continued  for  twenty  months  on  and  off 
(Spencer  Watson).  If  it  resists  local  applications,  plugging  of  the  nares  or 
nasal  fossae  (p.  82)  may  have  to  be  employed  to  arrest  a  fatal  result,  which 
has  occasionally  occurred.  The  great  vascularity  of  the  nasal  mucosa 
accounts  for  the  frequent  occurrence  of  epistaxis. 

The  Lymphatics.— The  lymphatics  communicate  through  the  cribriform 
plate  with  the  subdural  space,  and  also  enter  the  upper  nodes  of  the 


THE  XOSE,  NASAL  FOSS.fi  AND  ACCESSORY  SINUSES         87 

internal  jugular  chain  (deep  cervical),  the  submaxillary  and  retropharyn- 
geal nodes.  Abscess  of  the  last-named  nodes  may,  therefore,  be  due  to 
disease  of  the  nose,  and  in  lymphadenitis  of  the  cervical  nodes  we  are 
forced  by  exclusion  in  many  cases  to  assume,  if  we  cannot  prove,  that  the 
source  of  infection  was  in  the  nose  or  nasopharynx. 

The  Nerve  Supply. — The  nerve  supply,  apart  from  the  olfactory  nerve, 
whose  distribution  has  been  given  above,  is  from  the  first  and  second 
divisions  of  the  fifth  nerve.  The  nasal  branch  of  the  ophthalmic  division 
of  the  fifth  nerve  supplies  the  anterosuperior  part  of  the  nasal  fossae  and 
explains  the  following  reflexes  in  connection  with  other  branches  of  this 
division  of  the  nerve — i.  e.,  the  lacrymation  that  may  follow  a  pungent 
odor  and  the  sneezing  from  looking  at  bright  sunlight.  In  the  former  case 
the  irritation  is  referred  to  the  lacrymal  branch  of  the  same  division, 
and  in  the  latter  case  it  is  probably  referred  from  the  nerves  of  the  orbit 
to  the  nasal  branch.  Sneezing  also  follows  the  direct  irritation  of  the 
nerves  of  the  nose  by  chemical  or  mechanical  irritants  like  snuff  or  dust 
or  the  abnormal  contact  of  the  septum  and  outer  wall  of  the  nose.  In  the 
above  instances  sneezing  probably  depends  upon  the  relation  between 
the  trigeminus  and  vagus  nerves.  Curious  accidents  have  occurred 
during  violent  acts  of  sneezing.  Thus,  Treves  mentions  fracture  of  the 
ninth  rib,  dislocation  of  the  shoulder,  and  rupture  of  all  the  coverings  of 
a  large  femoral  hernia. 

The  lodgement  of  foreign  bodies  in  the  nose  is  quite  common.  That  they 
may  remain  in  some  cases  for  long  periods  of  time  without  causing  much 
trouble  is  illustrated  by  a  case  reported  by  Tillaux  of  an  old  woman  from 
whose  nose  he  removed  a  cherry  stone  that  had  lodged  there  for  twenty 
years.  When  they  remain  long  they  may  become  encrusted  by  calcareous 
matter  and  thus  form  rhinoliths  which  are  most  common  in  the  lower 
meatus.  In  some  cases  of  chronic  purulent  discharge  from  one  nostril 
the  cause  may  be  the  presence  of  a  bean,  bead,  button,  or  other  foreign 
body  in  the  nose. 

The  nasal  douche  may  be  used  in  more  than  one  way.  Thus,  with  the 
head  lowered  a  little  and  the  mouth  open,  the  nozzle  of  the  irrigator  is 
introduced  into  one  nostril  and  the  fluid  flows  out  of  the  other  after 
passing  from  one  fossa  to  the  other  behind  the  posterior  nares.  This  is 
possible  from  the  fact  that  in  breathing  through  the  mouth  the  palate  is 
elevated,  so  as  to  be  in  line  with  the  nasal  floor  behind  the  posterior  nares, 
and  shuts  off  the  nasal  fossa  from  the  pharynx.  But  at  the  same  time  the 
Eustachian  tube  is  opened  by  the  same  mechanism  that  raises  the  palate, 
and  there  is  some  danger  of  infection  being  carried  into  it.  Again,  with 
the  head  tilted  slightly  backward,  the  douche  may  be  allowed  to  flow 
bark  until  it  reaches  the  pharynx,  (lie  mouth  being  kept  closed. 

The  Accessory  Sinuses   of  the  Nose. — The  Frontal  Sinuses. — The 

frontal  sinuses  do  not  exist  at  birth,  but  their  evolution  occurs  between  the 

•  nth  and   twenty-first  years.      They  may   be  considered  as  developed 

from  tin-  diploe*  and  hence  lie  between  (Ik;  inner  and  outer  tallies  of  the 

skull,  or  they  may   be  Considered  as  prolongations  of  the  ethmoid  cells. 

The.  arerituated  above  and  externa]  to  the  nose,  above  and  internal  i<>  the 


gg  THE  HEAD  AND  NECK 

orbits,  and  beneath  and  in  front  of  the  cranial  cavity.  They  lie  on  either 
side  of  the  glabella  and  behind  the  superciliary  ridges,  whose  prominence 
they  form.  But  the  absence  of  these  prominences  does  not  necessarily 
imply  absence  of  the  sinuses,  as  they  may  extend  backward  only.  The 
orbital  and  cranial  walls  of  the  sinuses  are  formed  by  thin  bony  lamellae; 
the  anterior  wall  contains  a  small  amount  of  diploe.  The  sinuses  are 
divided  into  two  lateral  halves  by  a  septum,  often  thin  but  rarely  incom- 
plete, except  from  disease.  The  septum  is  median  inf  eriorly,  but  deviates 
to  one  side  above.  Sometimes  the  sinuses  are  so  small  as  to  be  scarcely 
noticeable;  at  other  times  they  may  be  large  enough  to  contain  two  or 
more  ounces,  or  to  contain  a  foreign  body  of  some  size.  In  old  people 
these  sinuses  may  enlarge  as  the  brain  shrinks.  Well-developed  sinuses 
may  extend  5  cm.  (2  in.)  upward,  3.5  cm.  (1 J  in.)  outward,  and  nearly  as 


Fig.  29 


SUPRA-ORBITAL/ 
NERVE 


FRONTAL  SINUS 


FRONTAL  BONE 


MAXILLARY   PROCESS 


NASAL  BONE 


TRIANGULAR 
CARTILAGE" 


ALAR    CARTILAGE 


FRONTAL  SEPTUM 

SUPRA-ORBITAL 
FORAMEN 


TROCHLEA 


LEVATOR    PALPEBRJE 
MUSCLE 


NASO-FRONTAL 
CANAL 


LACHRYMAL  DUCT 


MAXILLARY  SINUS 
NASAL  SEPTUM 


Frontal  sinus.     (Bardeleben.) 


far  backward,  but  the  average  size  is  nearly  one-third  less.  In  injury  to 
this  region  there  may  be  a  depressed  fracture  without  damage  to  the  cranial 
cavity.  In  this  case  air  may  be  forced  through  the  opening  on  blowing 
the  nose  and  cause  frothing  of  the  blood  if  the  fracture  be  compound,  or 
subcutaneous  emphysema  or  emphysema  of  the  orbit  in  a  simple  fracture. 
In  the  adult,  therefore,  fracture  here  is  less  serious  than  elsewhere  in  the 
skull,  as  the  brain-case  may  be  spared. 

Each  frontal  sinus  is  lined  by  a  pale,  thin,  loosely  adherent  mucosa 
continuous  with  that  of  the  middle  meatus  of  the  nose,  through  the 
infundibulum  in  about  half  the  cases,  and  through  a  separate  passage  or 
through  both  in  the  remaining  50  per  cent  of  cases.  Hence  they  are 
liable  to  an  extension  of  inflammation  from  the  nose,  which  accounts  for 
the  frontal  headache  in  some  cases  of  coryza,  ozena,  etc.    The  passage 


THE  NOSE,  NASAL  FOSSAE  AND  ACCESSORY  SINUSES         89 

to  the  nose  is  deeply  placed  near  the  inner  wall  of  the  orbit  and  its  open- 
ing into  the  infundibulum  is  about  on  a  line  with  the  tendo  oculi.  Bv 
the  swelling  of  the  mucosa  of  the  infundibulum  its  lumen  is  temporarily 
occluded.  The  upper  opening  of  the  duct  is  on  the  inner  and  back  part 
of  the  floor  of  the  sinus,  above  and  behind  the  internal  angular  process. 
The  duct  is  directed  downward  with  a  slightly  backward  curve,  through 
the  anterior  ethmoidal  cells,  and  is  well  placed  for  drainage.  But  when 
it  becomes  occluded  by  inflammatory  swelling  and  pus  forms,  we  have 
empyema  of  the  frontal  sinus  or  sinuses.  Eventually,  in  such  cases,  if 
drainage  is  not  provided,  the  walls  give  way  at  their  weakest  point,  which 
in  90  per  cent,  of  cases  is  in  the  orbital  roof,  and  the  abscess  finally  dis- 
charges through  the  inner  half  of  the  upper  lid.  Occasionally  the  pos- 
terior wall  of  the  sinus  is  eroded  and  perforated,  giving  rise  to  a  subdural 
abscess  or  pachymeningitis,  or  in  some  cases  meningitis  or  brain  abscess. 
The  anterior  ethmoidal  cells  are  not  infrequently  involved,  together  with 
the  sinus.  A  frequently  valuable  sign  of  this  complication  is  pain  local- 
ized at  the  inner  canthus  of  the  eye. 

The  frontal  sinuses  require  opening  by  the  chisel,  burr,  or  trephine  in 
cases  of  empyema,  and  are  generally  reached  by  a  horizontal  incision 
just  above  the  inner  half  of  the  supra-orbital  margin,  through  the  eye- 
brow.    The  reestablishment  of  drainage  into  the  nose  is  most  important. 

In  some  curious  cases  insects  like  centipedes,  larvce,  and  even  maggots 
have  found  their  way  into  the  frontal  sinuses,  in  the  latter  case  setting 
up  a  violent  septic  inflammation.  Bony  tumors  may  grow  from  the 
fibrous  layer  lining  the  deep  surface  of  the  mucosa. 
Y  The  Antrum  of  Highmore  or  Maxillary  Sinus  (Figs.  24  and  27).- — The 
antrum  of  Highmore  or  maxillary  sinus  is  present  at  birth,  but  continues 
to  grow  until  old  age,  when  its  walls  become  very  thin.  It  occupies  the 
body  of  the  maxilla  and  is  pyramidal  in  shape,  with  its  base  internally 
toward  the  nasal  fossa.  Its  anterior  or  facial  wall  is  the  thickest,  but 
the  most  accessible,  so  that  the  opening  of  an  empyema  of  the  antrum  is 
often  made  on  this  surface  above  the  first  or  second  molars,  after  incision 
of  the  mi  icons  membrane,  where  it  is  reflected  from  the  gums  to  the  cheek. 
Inflammation  and  empyema  of  the  antrum  may  be  due  to  the  diseased 
root  of  a  tooth,  especially  that  of  the  first  and  second  molars.  The  roots 
ot  1 1  if  latter  Intli  often  cause  a  prominencem  the  lower  part  of  the  an  (rum, 
and  may  even  project  uncovered  into  it.  In  diseased  conditions  (lie 
sockets  of  almost  any  of  the  teeth  may  communicate  with  i(.  When  the 
ed  root  of  a  first  or  second  molar  is  drawn  it  may  open  and  drain 
the  antrum  from  it-  lowest  point,  but  this  method  of  drainage  as  an  opera- 
tion of  choice  has  the  disadvantage  that  il  allows  food  particles  to  enter  the 
antrum.  Behind  the  antrum  is  the  sphenomaxillary  fossa  (Fig.  27)  con- 
taining Meckel's  ganglion,  to  remove  which  the  route  through  the  antrum, 
after   resecting  it-  facial   and   zygomatic    walls,  has   been    employed 

(Carnochan'fl  method).     The  upper  wall  separating  it  from   the  orbit   is 

'  r      thin,  so  that  tumor-  of  cither  of  these  eavities  readily  extend  into  the 

other.     Afl  this  wall  contain-  the  infra-orhilul  iicitc,  in  a  groove  and  canal, 

and    the  anterior  and    posterior   walls  contain    the   nerves   of   the   upper 


90  THE  HEAD  AND  NECK 

teeth,  tumors,  retained  pus,  etc.,  which  press  upon  these  walls,  are  likely 
to  cause  neuralgia  of  the  face  and  teeth.  The  inner  wall  or  base  corre- 
sponds to  the  outer  wall  of  the  nose  in  the  inferior  and  middle  meati,  in 
the  latter  of  which  at  the  lower  end  of  the  infundibulum  is  the  orifice 
of  the  antrum.  As  this  is  above  the  middle  of  the  cavity  it  is  not  well 
situated  for  drainage.  Sometimes,  in  about  10  per  cent,  of  cases,  there 
is  another  opening,  a  little  farther  back,  which  is  pathological  in  many 
cases.  This  wall  is  so  thin  as  to  be  readily  perforated.  Advantage  is 
taken  of  this  by  perforating  through  the  inferior  meatus  for  drainage 
in  the  treatment  of  empyema  of  the  antrum.  The  mucosa  of  the  nasal 
fossa  is  continuous  with  that  of  the  antrum,  and  in  this  way  inflammation 
may  extend  from  the  nose  to  the  antrum.  The  mucosa  of  the  antrum 
resembles  that  of  the  frontal  sinus,  but  is  somewhat  more  vascular  and 
more  richly  supplied  with  mucous  glands.  The  latter  are  quite  prone 
to  cystic  formation,  whereby  the  antrum  may  be  partly  or  wholly  filled, 
a  condition  sometimes  erroneously  called  dropsy  of  the  antrum. 

Tumors  of  the  upper  jaw  may  originate  in  the  antrum  or  grow  with 
great  rapidity  on  entering  it,  and  in  either  case  they  distend  its  walls. 
Thus,  pushing  up  the  roof,  they  invade  the  orbit,  causing  exophthalmos 
and  diplopia,  and  breaking  or  protruding  through  the  thin  inner  wall, 
they  obstruct  the  nasal  fossa  and  perhaps  the  nasal  duct.  They  pro- 
trude through  the  bottom  of  the  antrum  onto  the  roof  of  the  mouth  and 
also  form  a  projection  on  the  cheek.  The  treatment  for  malignant 
tumors  is  the  excision  of  the  upper  jaw;  for  benign  tumors,  their 
removal  through  an  opening  in  the  anterior  wall.  In  case  of  fracture 
of  the  anterior  wall  of  the  antrum,  emphysema  of  the  cheek  may  be 
present  and  may  be  increased  on  blowing  the  nose.  Occasionally  the 
antrum  is  subdivided  by  bony  septa  into  recesses  or  separate  chambers. 

As  to  the  sphenoidal  sinuses  little  need  be  said  except  that  like  the 
other  sinuses  of  the  face  they  serve  the  purpose  of  lightening  the  face, 
so  that  in  spite  of  its  growth  the  equilibrium  between  the  anterior  and 
posterior  parts  of  the  head  at  its  articulation  with  the  spine  is  not  dis- 
turbed. Also,  like  the  maxillary  sinus,  they  may  have  some  effect  on  the 
quality  of  the  voice,  acting  like  a  sounding  box.  Fracture  through  them 
leads  to  bleeding  from  the  nose,  and  may  establish  a  communication 
between  the  latter  and  the  cranial  cavity.  Dense  exostoses  occur  within 
them  as  within  the  frontal  sinuses,  and  inflammation  may  invade  them 
from  the  nasal  fossae  or  posterior  ethmoidal  cells. 


THE  FACE. 

This  region,  apart  from  the  eyebrows,  eyelids,  and  nose,  already 
studied,  and  the  parotid  region  and  lips,  to  be  considered  later,  we  will 
study  layer  by  layer.  The  lower  limit  of  this  region  and  the  boundary 
between  it  and  the  neck  is  the  lower  border  of  the  lower  jaw. 

The  Skin. — The  skin  of  the  face  is  for  the  most  part  thin,  fine,  elastic, 
and  very  vascular,  and  thus  well  suited  for  plastic  operations.    Its  vas- 


THE  FACE  91 

eulariiy  is  seen  in  the  ready  flushing  of  the  cheeks,  in  blushing  and  fever; 
in  the  free  bleeding  and  rapid  healing  of  wounds  or  incisions;  in  the 
varicose  or  injected  condition  of  its  fine  vessels  in  those  exposed  to  cold 
and  in  the  subjects  of  alcoholism  and  acne;  and  in  the  common  occur- 
rence of  nevi  and  various  forms  of  vascular  tumors.  Keloid-like  scars 
are  comparatively  common  on  the  face,  probably  owing  to  its  vascularity 
and  frequent  movement.  As  die  skin  is  richly  supplied  with  sebaceous 
and  sweat  glands,  it  is  a  favorite  site  for  acne  and  sebaceous  cysts.  The 
latter  sometimes  require  the  use  of  the  knife  to  avoid  a  more  disfiguring 
scar.  The  skin  of  the  face  is  also  a  favorite  situation  for  the  development 
of  rodent  ulcer  (epithelioma)  and  lupus.  Over  the  chin  the  skin  is  thick 
and  like  that  of  the  eyebrows.  When  the  skin  over  the  chin  or  that 
covering  the  malar  bone  is  struck  by  a  blunt  instrument  or  in  a  fall  a 
wound  may  be  produced  simulating  an  incised  wound,  as  is  also  the  case 
with  the  scalp. 

The  Subcutaneous  Layer. — The  subcutaneous  layer  is  in  general  lax, 
so  that  on  the  one  hand  it  favors  the  spread  of  inflammation,  edema, 
etc.,  and  on  the  other  hand  it  increases  the  mobility  of  the  skin  and  ren- 
ders it  suitable  for  the  various  plastic  operations  done  here.  In  inflam- 
mation or  edema  the  face  may  be  greatly  swollen  and  in  the  latter  condition 
the  swelling  first  appears,  as  a  rule,  in  the  loose  subcutaneous  tissue  of 
the  lower  lid.  The  quantity  of  fat  in  the  subcutaneous  tissue  varies  in 
different  parts  and  under  varying  circumstances.  Thus,  it  is  especially 
abundant  in  the  cheeks,  or  those  lateral  regions  corresponding  to  the 
area  lined  by  mucous  membrane  on  the  inner  surface.  It  is  firmer 
and  more  abundant  in  children  and  well-nourished  persons,  more  scanty 
in  old  age  and  after  wasting  diseases,  as  indicated  by  hollow  cheeks  and 
prominent  cheek  bones.    Fatty  tumors  are  exceedingly  rare  here. 

In  this  layer  lie  the  main  bloodvessels  of  the  face,  the  principal  branches 
of  the  facial  nerve  (in  front  of  the  anterior  border  of  the  masseter),  a 
lymph  node  near  the  lower  border  of  the  mandible  and  many  of  the  facial 
muscles  of  expression.  The  facial  artery,  where  it  crosses  the  lower  border 
of  the  mandible,  at  the  anteroinferior  angle  of  the  masseter,  lies  just  ante- 
riortoits  vein,  and  is  covered  by  the  skin  and  platysma  only.  Here  its  pul- 
sation scan  be  easily  felt  and  it  can  be  readily  compressed  against  the  bone 
or  ligated.  In  passing  toward  the  angle  of  the  mouth  and  the  ala  of  the 
and  thence  up  beneath  the  oasofacial  groove,  it  describes  the  arc  of 
a  curve  whose  chord  is  formed  by  the  straightei  and  more  superficial 
facial  vein.  The  free  communication  of  the  latter  with  the  cavernous 
sinus,  through  the  ophthalmic  vein,  explains  the  danger  of  intracranial 
complications  like  sinus-thrombosis,  in  case  of  septic  processes  of  the 
face,  such  as  ca rbuncle,  erysipelas,  malignant  pustule,  etc,  especially 

whin  thej  occni-  Dear  the  course  of  the  facial  vein,  along  which  the  infec- 
tion may  spread  as  a  phlebitis  or  periphlebitis. 

Malignant  piUtuU  attacks   the  face   more  often   than   any  other  part 

(even  the  hand  I.  Also  in  the  young  a  form  of  gangrene,  cancrwn  oris, 
sometimes  attacks  and  extensive!)  destroys  the  soft  parts  of  the  cheek  to 
such  an  extent  that  in  some  cases  the  jaws  may  be  firmly  closed  by  the 


92 


THE  HEAD  AND  NECK 


contraction  of  the  resulting  scar.  Owing  to  the  free  blood  supply  exten- 
sive flaps  in  plastic  operations,  or  even  those  torn  up  in  lacerated  wounds, 
keep  their  vitality  in  a  remarkable  manner.  As  the  anastomosis  is  very 
free  between  the  two  sides  of  the  face  or  two  adjoining  branches  of  the 
artery,  both  ends  of  a  divided  facial  artery  must  be  sought  and  tied  to 
check  bleeding.  The  lymph  node  near  the  vessels  as  they  cross  the 
border  of  the  mandible  is  often  enlarged  in  cases  of  alveolar  periostitis, 
etc.,  from  dental  caries.  Abscess  in  this  region  not  infrequently  originates 
in  this  way. 

p^The  Nerves. — The  branches  of  the  facial  nerve  are  nearly  horizontal  in 
direction.  They  anastomose  and  form  plexuses  with  the  infra-orbital, 
mental,  and  buccal  branches  of  the  fifth  nerve.  The  facial  nerve  supplies 
the  muscles  of  expression,  hence  in  facial  paralysis  there  is  a  lack  of  expres- 
sion on  the  side  paralyzed,  the  lines  of  the  face  are  flattened  out,  and  the 


Fig.  30 


Fig.  31 


Facial  paralysis  of  the  right  side. 
to  raise  the  eyebrows. 


Attempt 


Facial  paralysis  of  the  right  side, 
to  close  the  eyes. 


Attempt 


surface  is  smoother  than  normal.  The  cause  of  the  paralysis  may  be 
within  the  brain,  in  the  passage  of  the  nerve  through  the  skull  in  the 
aqueduct  of  Fallopius,  or  external  to  the  skull.  The  symptoms  help  us 
to  determine  the  position  of  the  lesion  according  as  one  or  another 
branch,  given  off  along  its  course,  is  affected  or  not.  In  a  very  few 
cases  deviation  of  the  uvula  has  been  noted,  but  this  is  now  thought  to  be 
a  mere  accident  (Horsley  and  Beevor),  and  the  levator  palati  and  azygos 
uvulae  muscles,  on  whose  paralysis  it  depends,  are  now  known  to  be 
supplied  by  the  spinal  accessory,  through  the  pharyngeal  plexus,  and  not 
by  branches  of  Meckel's  ganglion  derived,  through  the  great  superficial 
petrosal,  from  the  geniculate  ganglion.  Hence  the  condition  of  the 
palate  does  not  serve  to  locate  the  lesion  to  one  or  the  other  side  of 
the  geniculate  ganglion.  If  the  taste  is  lost  on  one  side  of  the  front  of 
the  tongue,  the  lesion  is  proximal  to,  if  it  is  not  lost  it  is  distal  to,  the 
origin  and  giving  off  of  the  chorda  tympani  branch  in  the  lower  part  of 


THE  FACE  93 

the  Fallopian  aqueduct,  for  this  branch  conveys  taste  fibers  from  the 
glossopharyngeal  nucleus  to  the  tongue.  Just  below  the  aqueduct  there 
is  given  on"  the  posterior  auricular  branch  which  supplies  the  posterior 
belly  of  the  occipitofrontalis  and  the  retrahens  and  attollens  aurem,  so 
that  these  muscles  are  paralyzed  if  the  lesion  is  proximal  to  this  branch, 
but  not  if  it  is  distal  to  it,  and  so  on. 

As  the  orbicularis  palpebrarum,  frontalis,  and  corrugator  supercilii 
muscles  are  not  involved  in  facial  paralysis  due  to  a  lesion  of  the  cortical 
facial  centre  of  the  brain,  it  is  probable  diat  the  fibers  which  supply  them 
reach  the  facial  nerve  from  the  oculomotor  nucleus,  or  that  these  fibers 
receive  a  bilateral  innervation.  Also  the  involvement  of  the  orbicularis 
oris  in  bulbar  paralysis  and  the  close  association  of  the  movements  of  the 
lips  and  tongue  suggest  that  this  muscle  is  supplied  from  the  hypoglossal 
nucleus  through  the  facial. 

The  chief  features  of  facial  paralysis  are  a  smooth  forehead  and 
immovable  eyebrow,  the  inability  to  wink  or  close  the  eye,  so  that  the 
eyeball  is  aways  exposed,  the  dripping  of  tears  over  the  cheek  (see  p. 
70),  a  flat,  flabby  cheek  between  which  and  the  gums  food  lodges,  the 
inability  to  whistle  or  pucker  the  mouth,  and  an  expressionless  drooping 
corner  of  the  mouth,  with  or  without  partial  loss  of  taste.  Electricity 
can  be  applied  to  the  nerve  or  its  branches;  to  the  undivided  trunk  by  an 
electrode  pressed  as  deeply  as  possible  between  the  mastoid  process  and 
the  cartilaginous  auditory  meatus.  If  the  paralysis  persists,  it  may  be 
largely  relieved  by  anastomosis  of  the  distal  end  of  the  nerve,  severed 
as  it  emerges  at  the  stylomastoid  foramen,  with  the  spinal  accessory  or 
hypoglossal  nerve. 

Below  its  exit  from  the  stylomastoid  foramen  the  facial  nerve  is  acces- 
sible to  surgical  procedure  through  a  curved  or  straight  incision  in  front  of 
the  mastoid  process  and  the  sternomastoid  muscle.  The  latter  is  retracted 
backward  and  the  parotid  gland  forward,  and  by  blunt  dissection  the 
styloid  process  is  reached,  behind  which  the  trunk  of  the  nerve  emerges. 
This  is  short  and  soon  enters  the  parotid  gland,  in  which  it  branches  and 
forms  a  plexus,  pes  anserinus.  In  peripheral  operations  for  trigeminal 
neuralgia  it  is  important  to  spare  the  temporal  branch,  which  emerges 
from  the  upper  end  of  the  parotid  just  in  front  of  the  temporal  artery, 
and  supplies  the  orbicularis  palpebrarum.  If  the  operation  on  the 
serian  ganglion  should  become  necessary,  the  functional  activity  of 
this  muscle  in  winking  is  important  in  preserving  the  integrity  of  the 
eyeball. 

The  facia]  nerve  is  liable  to  be  injured  within  the  parotid  or  distal  t<> 
it.  Within  the  skull  it  is  more  often  injured  in  fractures  of  the  base 
of  the  skull  thai]  any  other  nerve,  owing  to  its  long  course  through  the 
bony  Fallopian  canal. 

Though  the  main  trunks  of  the  sensory  nerves  belong  to  the  deepest  layer 

of  the  face,  their  filaments  |>;iss  through  tin;  subcutaneous  layer  to  reach 
the  skin.     To  Complete   the  Study  of  the  nerves  of  the  face  they  are  best 

considered  here.  For  their  distribution  see  Fig.32.  They  are  branches 
of  (he  fifth  nerve,  and  three  such  branches  concern  the  region  under  eon- 


94 


THE  HEAD  AND   NECK 


sideration.  The  infra-orbital  branch  of  the  maxillary  (second)  division  of 
the  fifth  nerve,  after  passing  along  a  groove  and  then  a  canal  in  the  floor 
of  the  orbit  (and  the  roof  of  the  antrum),  emerges  on  the  face  at  the 
infra-orbital  foramen.  This  is  situated  at  the  upper  end  of  the  canine 
fossa,  S  mm.  (^  in.)  below  the  inferior  margin  of  the  orbit,  near  the 
junction  of  its  middle  and  inner  thirds  and  in  a  vertical  line  from  the 
interval  between  the  two  upper  bicuspids  or  from  the  second  bicuspid. 
This,  the  most  frequently  affected  nerve  in  trigeminal  neuralgia,  may 
be  reached  and  injected  with  osmic  acid  or   alcohol,  or  resected   by 


Fig.  32 


Schematic  drawing  of  the  sensory  nerves  of  the  head  according  to  F.  Frohse  (from  F.  Krause, 
Die  Neuralgie  des  Trigeminus,  etc.,  Leipzig,  1896).  Area  of  the  first  (1)  and  third  (3)  trigeminal 
branch  shaded  transversely;  area  of  the  auricular  branch  of  vagus  black:  1,  first  trigeminal, 
branch;  2,  second  trigeminal  branch:  2  o,  infra-orbital  nerve;  2  6,  malar  branch  of  the  second 
division;  2  c,  temporal  branch  of  the  second  division;  3,  just  in  front  of  the  auriculotemporal  nerve; 
4,  occipitalis  major  nerve;  5,  occipitalis  minor  nerve;  6,  auricularis  magnus  nerve;  7,  posterior 
(dorsal)  cervical  nerve;  8,  lateral  (ventral)  cervical  nerves;   9,  auricular  branch  of  the  vagus. 

incising  the  mucous  membrane  above  the  bicuspids  and  separating  the  soft 
parts  from  the  bone,  or  by  an  oblique  or  angular  cutaneous  incision  below 
the  orbit.  By  lifting  up  the  contents  of  the  orbit  from  its  floor  the  nerve 
is  exposed  in  the  bony  groove  in  which  it  lies,  and  that  part  of  it  may  be 
resected  which  lies  between  the  groove  and  the  foramen  and  the  latter 
securely  plugged  to  prevent  regeneration  of  the  nerve.  The  small  arterial 
branch  accompanying  the  infra-orbital  nerve  may  usually  be  disregarded. 
Meckel's  ganglion,  together  with  the  infra-orbital  branch  behind  the 
orbit,  has  often  been  resected  for  certain  neuralgias  of  the  second  division 


THE  FACE 


95 


of  the  fifth  nerve  by  following  the  infra-orbital  nerve  backward  (Carno- 
chan's  operation).  Thus,  after  incising  below  the  orbit  and  then  down 
the  nasofacial  groove,  a  flap  of  skin  is  turned  back  and  the  anterior  wall 
of  the  antrum  opened,  up  to  the  infra-orbital  foramen.  The  bony  canal 
and  groove  of  the  nerve  is  then  laid  open  from  beneath,  and,  following 
the  nerve,  the  posterior  wall  of  the  antrum  is  trephined,  opening  into  the 


Scheme  showing  effects  of  total  extirpation  of  Gasserian  ganglion  forty-seven  days  after  opera- 
tion. Sensation  of  heat  spoken  of  as  slightly  warm;  sensation  of  cold  absent:  Vx  V2  V3,  first, 
second,  and  third  branches  of  fifth  nerve;  oma,  occipitalis  major;  ami,  occipitalis  minor;  am, 
auricularis  rnagnus;  cs,  cervical  nerves.      (Freidrich.) 


Zone  of  absolute  anaesthesia  and  analgesia;  complete  loss  of  temperature  area. 


□ 
□ 


Zone  of  marly  complete  anaesthesia  ami  analgesia. 

Zone  of  distinct  but  diminished  hypeigesia  and  hyperesthesia. 


Area  <>f  norma]  sensation 

Outline  of  innervation  Eonesof  trigeminal. 


§phenomaxillary  fossa  (Fig.  27).    This  exposes  the  triangular  reddish 

ganglion  0.5  cm.  <  \  in.)  in  diameter,  lying  below  the  main  nerve.     The 

terminal  branches  of  the  internal  maxillary  artery  are  in  close  relation  to 

the  ganglion  and  n.  o  considerable  hemorrhage,  which  may  be 

stopped  by  pres  Hire.    External  to  the  ganglion  and  nerve  is  the  external 

goid  muscle,  internal  to  it  the  vertical  plate  of  the  palate  bom-  and 

ibenopalatine  foramen.    Behind  the  ganglion  the  nerve  trunk  can 


96 


THE  HEAD  AND  NECK 


be  followed  back  through  the  sphenomaxillary  fossa  to  the  foramen 
rotundum.  Peripheral  operations  on  the  branches  of  the  second  and 
third  divisions  of  the  fifth  nerve  give  only  temporary  relief,  as  a  rule,  in 
tic  douloureux,  but  the  nearer  the  foramina  of  exit  the  nerves  are  excised 
or  avulsed  the  longer  does  this  relief  persist.  There  are  many  other 
methods  of  exposure  of  this  branch. 

The  mental  branch  of  the  inferior  dental  trunk  of  the  mandibular 
division  of  the  fifth  nerve  emerges  at  the  mental  foramen,  below  the 
interval  between  the  two  lower  bicuspids  or  below  the  second  bicuspid. 


MALAR    BRANCH   OF 

ORBITAL  NERVE  \TEM POR AL  M USCLL  |     TEMPORAL 


TEMPORAL  BRANCH 
OF  ORBITAL   NERVE 


INFRAORBITAL    NERVE 


SUPERIOR    DENTAL 
NERVES 


STENSON'S    DUCT 


BICHAT'S    LOBULE 


BUCCINATOR     MUSCLE 


BUCCINATOR    NERVE 


Fig.  34 

posterior 
temporal  artery 

and  nerve  masseter  branch 

superficial 
:    c  te^poralahterv 

articular 

INENCE 


AURICULO- 
TEMPORAL 
NERVE 


EXT.    PTERYGOID 

MUSCLE 

RAMUS  COMMUNICANS 

OF  FACIAL  AND  AORIC- 

ULO-TEMPORAL 

NERVES 

MIDDLE   MENINGEAL  I 

ARTERY 


FACIAL  NERVE 


INTERNAL 

MAXILLARY 

ARTERY 


711 

INTERNAL 

PTERYGOID 

MUSCLE 


Lateral  view  of  the  face.      Deep  layer.      (Bardeleben.) 

It  is  thus  seen  to  lie  in  the  same  vertical  line  with  the  infra-orbital  foramen, 
and  if  this  line  is  continued  upward  it  strikes  the  supra-orbital  notch  or 
foramen.  Hence  these  three  branches  of  the  three  divisions  of  the  fifth 
nerve  emerge  through  bony  openings  in  the  same  vertical  line.  In  tic 
douloureux  there  are  usually  "  tender  points"  where  the  affected  branches 
emerge  on  the  face,  pressure  at  which  may  bring  on  a  paroxysm.  The 
mental  foramen  in  the  adult  is  midway  between  the  lower  and  the  alveolar 
borders  of  the  jaw,  in  the  aged  near  the  latter,  in  the  infant  near  the 
former.    It  may  be  exposed  by  a  cutaneous  incision  or  by  one  through  the 


THE  FACE  97 

gingivolabial  fold  of  mucous  membrane,  remembering  that  the  foramen 
lies  8  mm.  (J  in.)  below  this  fold.    Its  exposure  is  not  often  indicated. 

The  main  trunk  of  this  nerve,  the  inferior  dental,  may  be  exposed  for 
exsection  at  its  entry  into  the  inferior  dental  foramen  in  one  of  several 
ways.  The  foramen,  it  should  be  remembered,  is  about  equidistant  from 
all  four  borders  of  the  ramus ;  that  is,  about  the  centre  of  the  inner  surface. 
Surmounting  the  foramen  in  front  is  the  mandibular  spine,  to  be  used  as 
a  landmark  when  we  expose  the  nerve  at  its  entrance  into  the  foramen. 
This  is  done  from  within  the  mouth  by  incising  the  mucous  membrane 
from  the  last  upper  molar  to  the  inner  side  of  the  coronoid  process,  thus 
exposing  the  tendon  of  the  temporal  muscle.  The  finger  is  then  intro- 
duced backward  between  the  ramus  of  the  jaw  and  the  internal  pterygoid 
muscle  until  the  mandibular  spine  is  felt.  Thereupon  the  nerve  is  hooked 
forward  by  a  blunt  hook,  isolated  from  its  accompanying  vessels,  divided 
and  both  ends  avulsed,  or  a  piece  resected. 

From  the  outside  we  may  expose  the  nerve  by  an  angular  incision  of 
3  cm.  (1£  in.)  upward  and  5  cm.  (2  in.)  forward  from  the  angle  of  the  jaw. 
The  periosteum  of  the  borders  of  the  ramus  is  divided  to  the  same  extent 
and  then  stripped  up  from  the  inner  surface  until  the  mandibular  spine 
is  reached.  Again,  it  may  be  exposed  by  resection  of  the  angle  or  posterior 
border  of  the  ramus  of  the  jaw,  or  by  a  horizontal  incision  over  the  middle 
of  the  ramus,  retracting  Stenson's  duct  upward,  separating  the  fibers  of 
the  masseter  vertically,  dividing  the  periosteum  in  the  same  line,  and 
trephining  or  chiselling  through  the  centre  of  the  ramus. 

The  buccal  nerve  (Fig.  35)  is  another  sensory  branch  of  the  fifth  nerve, 
sometimes  affected  by  neuralgia,  which  is  felt  in  the  skin  and  mucosa  of 
cheek  and  lips.  It  may  be  exposed  from  within  or  without  the  mouth. 
As  the  nerve  courses  forward  on  the  inner  surface  of  the  temporal  muscle, 
near  its  insertion  on  the  coronoid  process,  it  is  only  covered  on  its  buccal 
surface  by  the  mucous  membrane,  buccinator  muscle,  and  fatty  tissue,  so 
that  it  may  be  exposed  by  dividing  the  latter  layers  vertically  behind  the 
last  molar.  From  the  outside  it  may  be  exposed  by  a  transverse  incision 
<>f  .")  cm.  (2  in.)  over  the  course  of  Stenson's  duct  (see  p.  98),  which  with 
flu-  accompanying  nerves  is  retracted  upward  or  downward.  The  fatty 
tissue  Bichat's  lobule)  between  the  buccinator  and  masseter  is  removed 
or  retracted,  and  the  nerve  is  seized  opposite  the  insertion  of  the  tem- 
poral muscle,  about  2.5  cm.  (1  in.)  behind  the  anterior  border  of  the 
masseter.  When  the  neuralgia  involves  several  branches,  or  shifts  from 
our  to  another,  or  recurs  after  peripheral  operations,  a  central  involve- 
ment is  indicated  and'the  Gasserian  ganglion  or  its  sensory  root  should 
be  resected  (p.  •''>'>). 

'  In  any  operation  on  the  face  transverse  incisions  are  preferable  and 
vertical  incisions  objectionable  because  of  the  danger  of  wounding  im- 
portant Structures  having  a  transverse  course.  These  are  the  branches 
of^thr-  facial  nerve,  already  mentioned,  ami  the  dial  of  Stm-on,  whose 
COUne  i  L'ivm  below.  This,  the'excretory  duct  of  the  parotid  gland,  is 
beneath  the  deep' fascia,  which  forms  (he  next  of  the  several  layers  of  this 

region.    This  fascia  is  continued  forward  from  the  parotid  gland,  of 

7 


98 


THE  HEAD  AND  NECK 


which  it  forms  the  sheath.  The  two  layers  of  the  parotid  sheath  unite 
and  form  the  fascial  covering  of  the  masseter  and,  in  front  of  this,  of  the 
buccinator.  Beneath  the  masseteric  fascia  lie  the  branches  of  the  facial 
nerve  which  (except  the  buccal  branches)  pierce  it  at  the  anterior  border 
of  the  muscle. 

Stenson's  Duct. — Stenson's  duct,  3  mm.  (\  in.)  in  diameter,  extends 
forward  for  5  to  6.5  cm.  (2  to  2\  in.)  from  the  anterior  border  of 
the  parotid  gland  to  the  opening  of  the  duct  on  the  buccal  mucosa, 
opposite  the  crown  of  the  second  molar  tooth,  4  mm.  (-g-  in.)  below  the 
reflection  of  the  mucosa  from  the  gums  to  the  cheek  and  about  33  mm. 
(1^  in.)  behind  the  angle  of  the  mouth.    The  course  of  the  duct  is  a  finger's 

Fig.  35 
temporal 

MUSCLE 


BUCCAL    NER 
EXTERNAL   PTERYGO 
MUSCLE 
MASSETER    MUSCL 
INFERIOR    DENTA 
NERVE 
BUCCINATOR    MUSCL 
LINGUAL    NERV 


Zygomatic  fossa  and  adjacent  parts  as  seen  when  exposed  from  the  vestibule  of  the  mouth. 

(Zuckerkandl.) 


breadth,  or  18  mm.  (f  in.),  below  the  zygoma  or  in  a  line  from  the  lower 
end  of  the  concha  of  the  ear  to  the  midpoint  of  the  upper  lip.  The  pos- 
terior or  masseteric  portion  crosses  the  middle  of  the  masseter,  having 
the  soda  parotidis  above  or  superficial  to  it,  the  transverse  facial  artery 
above  it,  and  the  buccal  branch  of  the  facial  nerve  below  it.  It  then  bends 
sharply  inward  through  the  fat  of  the  cheek  to  the  buccinator  muscle, 
through  which  the  anterior  or  buccal  portion  runs  obliquely  forward  and 
then  for  a  short  distance  between  the  muscle  and  the  lining  mucosa  to  its 
termination. 

The  bends  in  its  course  should  be  remembered,  for  in  passing  a  probe 
through  it  they  should  be  straightened  out  by  pulling  forward  the  angle 
of  the  mouth.    The  course  of  the  duct  should  be  borne  in  mind  so  as  to 


PLATE    IV 


FIG.  36 


FACIAL 
NERVE 
PAROTID 
APONEU- 
ROSIS, 
SUPERFIC 
LAYER 


TEMPORO- 

^\  MAXILLARY 

VEIN 


EXTERNAL 
CAROTID 
ARTERY 

PHARYN- 
GEAL 
WALL 


STYLOID 
PROCESS 
AND    ITS 
MUSCLES 


Horizontal  Section  through  the  Left  Parotid  Compartment. 
Diagrammatic.  Arrow  indicates  the  pharyngeal  opening  of 
the  compartment.     (Testut.) 


FIG.  37 


EXT.    AUDITORY 
CANAL 


Frontal  Section  through  the  Right  Parotid  Compartment, 
to  show  its  relations.  Diagrammatic.  Arrow  indicates  the 
pharyngeal  opening  of  the  compartment.     (Testut.) 


THE  FACE  99 

avoid  it  in  any  incision  in  the  cheek,  for  its  division  may  be  followed  by 
an  obstinate  salivary  fistula.  This  is  particularly  troublesome  in  the 
posterior  or  masseteric  portion  where  successful  conservative  treatment 
is  not  easy  to  provide  except  by  an  anastomosis  between  the  divided  ends, 
a  difficult  matter  on  account  of  its  small  size,  or  a  plastic  operation.  In 
the  anterior  or  buccal  portion  of  the  duct  a  salivary  fistula  may  be  suc- 
cessfully  treated  by  stitching  the  proximal  end  of  the  duct  into  an  open- 
ing in  the  buccal  mucosa  made  by  incising  through  the  buccinator, 
behind  its  normal  opening. 

The  duct  is  surrounded  by  a  fibrous  sheath  continued  forward  from 
the  parotid  sheath  and  by  a  fibrous  sheath  of  its  own.  Both  of  these 
sheaths  leave  it  where  it  penetrates  the  buccinator  and  there  become 
continuous  with  the  fascial  covering  of  this  muscle.  Inflammation  may 
travel  back  along  the  duct  to  the  gland  from  the  buccal  cavity  in  case  of 
stomatitis  or  lack  of  cleanliness  in  the  latter.  It  is  not  unlikely  that  this 
Is  the  route  of  infection  in  some  cases  of  acute  parotitis  complicating 
acute  infectious  diseases.  Hence  the  importance  of  the  care  of  the  mouth 
in  these  conditions. 

Between  the  buccinator  and  its  fascia  and  behind  Stenson's  duct  is  a 
group  of  deep  buccal  or  molar  glands  which  may  be  the  origin  of  cysts 
or  adenoma.  They  are  opposite  the  last  two  molars.  Behind  these  and 
filling  the  space  between  the  buccinator  and  the  masseter  is  a  fad  of 
fat,  the  buccal  fat  pad  or  "Bichat's  lobule."  This  is  quite  constant, 
even  in  emaciated  conditions,  but  if  it  be  absorbed  in  wasting  diseases 
a  marked  hollow  of  the  cheek  is  produced  in  front  of  the  masseter.  A 
swelling,  from  lipoma  or  abscess  in  this  situation,  points  in  the  mouth,  as 
it  is  beneath  the  buccal  fascia.  In  case  of  abscess  it  is  to  be  noticed  that 
tins  fat  is  continuous  with  the  fat  and  loose  areolar  tissue  in  the  temporal 
and  zygomatic  fossae  and  that  which  covers  the  upper  part  of  the  pharynx. 
The  mucous  membrane  lining  the  buccinator  is  thin  and  directly  adherent 
to  the  muscle  without  submucous  tissue  between. 

The  Parotid  Region. — Superficially  this  is  bounded  in  front  by  the  pos- 
terior  border  of  the  mandible;  behind  by  the  mastoid  process  and  sterno- 
mastoid  muscle;  above  by  the  auditory  meatus,  the  condyle  of  the  jaw, 
and  the  posterior  part  of  the  zygoma;  below  by  a  line  from  the  angle  of 
the  jaw  to  the  sternomastoid  muscle,  outlined  by  a  thickened  band  of  the 
cervical  fascia.  The  surgical  anatomy  of  this  region  is  most  important 
on  account  of  the  important  parts  in  relation  or  contiguity  with  the 
parotid  gland  which  occupies  it. 

This  gland  is  lodged  in  a  narrow  and  deep  but  well-defined  space,  the 
parotid  compartment,  which  is  bounded  as  follows:  Behind  by  the  sterno- 
mastoid, the  po  terioT  belly  of  the  digastric  and  the  mastoid  process; 
in  front  by  the  posterior  border  of  the  ramus  of  the  jaw,  covered  by  the 
masseter  and  internal  pterygoid  muscles;  above  by  the  external  auditory 
meatus  and  the  posterior  pari  of  the  glenoid  fossa;  below  by  the  stylo- 
maxillary  ligament  wliicli  separates  the  parotid  from  ili<-  posterior  end 
of  the  iibmaxillary  gland;  internally  by  the  styloid  process  and  its 
muscles,  which  leparate  it  from  the  Internal  carotid  and  internal  jugular 


100 


THE  HEAD  AND  NECK 


with  their  accompanying  nerves,  and,  in  front  of  these,  from  the  loose 
tissue  around  the  pharynx. 

Within  these  limits  the  parotid  is  enclosed  within  a  distinct  sheath 
which  is  derived  from  the  deep  cervical  fascia.  At  the  anterior  border 
of  the  sternomastoid  the  fascia  which  has  formed  the  sheath  of  that  muscle 
again  divides  into  two  layers,  one  of  which  passes  internal  and  the  other 


Fig.  38 
auriculo- 

MALAR    BRANCH    TEMPORAL 
TEMPORAL  BRANCH  OF   ORBITAL  NERVE 

OF   ORBITAL    NERVE  NERVE 


SUPERFICIAL 

TEMPORAL 

ARTERY 


TEMPORAL 
VEIN 


FACIAL   NERVE 
TRUNK 


AURICULAR 


EXTERNAL 

JUGULAR 

VEIN 


PAROTID   GLAND 


NERVE 

FACIAL  VEIN 


Lateral  view  of  the  face.     Superficial  layer.      Parotid  dissected  so  as  to  show  contents. 

(Bardeleben.) 


external  to  the  gland.  These  layers  unite  in  front  of  the  gland  to  become 
continuous  with  the  fascia  covering  the  masseter;  and  below  the  gland 
they  unite  along  the  thickened  band  between  the  angle  of  the  jaw  and  the 
sternomastoid  muscle.  From  this  band  the  inner  layer  passes  inward 
and  upward  on  the  outer  aspect  of  the  styloid  process  and  its  muscles, 
forming  the  sheath  of  these  muscles  and  becoming  attached  to  the 
styloid  process. 


THE  FACE  101 

Internally  the  parotid  sheath  is  deficient  in  front  of  the  styloid  process, 
between  it  and  the  internal  pterygoid  muscle,  where  an  uncovered  pro- 
longation of  the  gland  projects  inward  into  relationship  with  the  pharyn- 
geal wall,  in  front  of  the  great  vessels,  etc.  Hence  abscess  or  tumors  of  the 
parotid  are  unopposed  by  the  sheath  in  spreading  inward  toward  the 
pharynx.  Also  in  postpharyngeal  abscesses  there  is  often  a  parotid 
swelling  and  sometimes  the  abscess  evacuates  through  the  parotid. 
Anteriorly  there  is  a  process  of  the  gland,  socia  parotidis,  prolonged  for- 
ward a  variable  distance  on  the  surface  of  the  masseter,  above  or  over- 
lying Stenson's  duct,  and,  like  the  latter,  covered  by  a  prolongation  of  the 
parotid  sheath.  In  inflammation  or  tumor  of  the  parotid,  therefore,  the 
swelling  may  extend  forward  onto  the  surface  of  the  masseter.  Superiorly 
the  sheath  is  incomplete,  being  attached  externally  to  the  inferior  border 
of  the  zygomatic  arch  and  the  outer  part  of  the  cartilaginous  auditory 
meatus,  internally  to  the  base  of  the  styloid  process,  the  free  border  of 
the  vaginal  process,  and  the  Glaserian  fissure.  Hence  between  the  outer 
and  inner  layers  of  the  sheath  superiorly  the  gland  is  in  direct  contact, 
without  intervening  fascia,  with  the  external  auditory  meatus  and  the 
posterior  part  of  the  glenoid  fossa.  This  accounts  for  the  ease  with  which 
inflammations  of  the  parotid  extend  to  the  external  auditory  meatus  or  the 
periosteum  of  the  adjacent  bones,  or  vice  versa  (see  pp.  54  and  55). 

As  a  portion  of  the  gland  occupies  the  posterior  part  of  the  glenoid 
fossa  it  comes  in  direct  relation  with  the  capsule  of  the  temporomandibular 
joint,  which  explains  in  part  the  pain  of  moving  the  jaw  in  cases  of  parotid 
inflammation,  like  mumps,  abscess,  etc.,  and  the  occasional  extension 
of  inflammation  of  the  gland  to  the  joint.  The  pain  is  also  accounted  for 
by  the  fact  that  in  movements  of  the  jaw,  like  retraction  or  opening, 
the  parotid  compartment  is  encroached  upon  and  the  gland  pressed  upon 
by  the  ramus  or  its  angle,  and  thus  the  pain  of  an  inflamed  parotid  is 
aggravated. 

The  fact  that  the  size  of  the  parotid  compartment,  and  especially  that 
of  its  superficial  boundaries,  is  altered  by  the  position  of  the  jaw,  which 
occupies  a  groove  on  its  anterior  surface,  should  also  be  remembered  in 
operations  on  this  narrow  region,  in  which  we  need  all  the  space  available. 
Thus,  it  may  be  increased  anteroposterior^'  by  about  1  cm.  (f  in.)  by  a 
simple  protrusion  of  the  jaw  and  to  a  certain  extent  by  extension  of  the 
head,  whereby  the  sternomastoid  is  separated  from  the  ramus.  It  is 
narrowed  in  the  opposite  movements.  In  opening  the  mouth  it  is 
narrowed  inferiorly  but  widened  superiorly  by  (lie  gliding  forward  of 
the  condyle.  The  obliquity  of  the  ramus  in  infancy  and  old  age  widens 
tin-  lower  pari  of  the  space. 

The  strength  of  the  fascia  superficial  to  the  parotid  oilers  much  resist- 
ance to  the  spontaneous  opening  of  a  parotid  abscess  in  this  direction. 
In  addition  to  the  directions  indicated  above,  an  abscess  may  also  extend 
downward  to  the  neck,  upward  into  the  t<niporal  fossa,  or  forward  toward 
the  buccal  cavity,  internal  to  the  ramus  where  the  sheath  is  weaker  and 
i->  penetrated  by  the  carotid.  Pus  within  the  gland  may  also  occasionally 
|  m  along  a  vessel  or  nerve  where  it  perforates  the  investing  fascia. 


102  THE  HEAD  AND  NECK 

From  the  inner  surface  of  the  enveloping  fascial  sheath  fibrous  pro- 
cesses extending  inward  divide  the  gland  into  lobules  and  support  the 
vessels  and  nerves  which  pass  through  it  or  supply  it.  To  these  tra- 
becular the  vessels  adhere  so  intimately  that  it  is  practically  impossible 
to  remove  the  gland  and  spare  the  vessels.  Although  the  nerve  trunks 
are  less  intimately  adherent,  yet  in  the  living  subject,  especially  where  the 
entire  gland  is  occupied  by  a  tumor,  it  is  impracticable  if  not  impossible 
to  remove  the  gland  and  spare  the  nerves  also.  This  fibrous  framework 
is  the  seat  of  the  inflammation  in  the  specific  parotitis  known  as  mumps. 
Acute  parotitis  also  occurs  as  a  complication  in  septic  conditions,  in  acute 
infectious  diseases,  such  as  typhoid  fever  and  more  rarely  pneumonia, 
and  after  injuries  and  diseases  of  the  abdomen  and  pelvis.  Abscess 
formation  is  to  be  expected  in  such  conditions,  and  the  pressure  on  the 
small  vessels  may  occlude  them  and  cause  a  necrosis  of  the  lobules  of 
the  gland  supplied  by  them. 

Contained  within  and  passing  through  the  gland  are  many  important 
structures.  The  facial  nerve  passes  forward  through  the  gland  from 
the  postero-internal  aspect,  with  an  inclination  outward  and  slightly 
downward.  Its  entry  into  the  parotid  corresponds  to  the  point  where 
the  anterior  border  of  the  mastoid  meets  the  external  auditory  meatus. 
It  lies  superficial  to  the  main  arterial  and  venous  trunks  and  breaks  up, 
after  an  undivided  course  of  about  2  cm.  (f  in.),  into  a  plexus  which 
emerges  at  the  anterior  and  upper  border  of  the  gland,  after  being  joined 
by  branches  of  the  auriculotemporal  nerve  (see  also  p.  92).  The  latter 
sensory  branch  of  the  inferior  maxillary  division  of  the  fifth  nerve  passes 
from  within  upward  and  outward  through  the  upper  part  of  the  gland 
to  emerge  at  its  upper  border.  Thence  it  crosses  the  root  of  the  zygoma 
between  the  ear  and  the  temporal  artery,  where  it  may  be  exposed  and 
resected.  The  pain  of  a  parotitis  and  of  some  parotid  tumors  may  be 
referred  along  the  course  of  this  nerve.  The  presence  of  the  latter  and  of 
the  great  auricular  nerve,  supplying  the  gland  with  sensation,  within  the 
unyielding  parotid  fascia  accounts  for  the  severity  of  this  pain. 

The  external  carotid  artery  lies  under  cover  of  the  ramus  of  the  jaw 
up  to  the  junction  of  the  middle  and  lower  thirds  of  its  posterior  border, 
where  it  enters  the  internal  or  deep  surface  of  the  parotid  quite  anteriorly. 
Thence  it  continues  through  the  upper  three-fourths  of  the  gland  in  a 
direction  upward,  outward,  and  slightly  backward  to  behind  the  neck 
of  the  condyle  of  the  jaw,  where,  having  become  more  superficial,  it 
divides  into  its  two  terminal  branches.  These  branches,  the  superficial 
temporal  and  internal  maxillary  arteries,  together  with  the  posterior 
auricular  and  sometimes  the  occipital,  are  within  the  parotid  at  their 
commencement.  Within  the  gland  the  artery  is  separated  from  the 
internal  carotid,  and  the  accompanying  internal  jugular  vein,  vagus, 
glossopharyngeal,  and  sympathetic  nerves,  by  the  styloid  process  and  its 
muscles,  the  parotid  fascia,  and  a  varying  thickness  of  gland  tissue. 

It  may  be  difficult  at  times  to  tell  the  source  of  arterial  hemorrhage  in 
a  deep  parotid  wound.  But  in  general,  if  the  source  of  the  bleeding  can- 
not be  found  and  both  ends  tied,  it  is  best  to  expose  and  tie  the  external 


THE  FACE  103 

carotid  first,  and  then  if  necessary  the  internal  carotid,  not  the  common 
carotid.  It  is  evident  from  its  relations  that  the  styloid  process  is  a  most 
important  landmark  in  extensive  operations  on  the  parotid,  for  it  indicates 
its  inner  boundary,  the  position  of  its  prolongation  toward  the  pharynx 
and  of  the  deep  vessels. 

The  temporomaxillary  vein  lies  superficial  to  the  artery,  and  usually 
divides  within  the  parotid  into  its  two  divisions,  one  of  which  continues 
downward  to  the  lower  border  of  the  gland  to  become  the  external 
jugular,  while  the  other,  passing  downward  and  forward,  joins  the  internal 
jugular.  The  number,  size,  and  deep  situation  of  the  vessels  in  the 
narrow  and  deep  parotid  region  accounts  for  the  gravity  of  wounds  of 
this  region  when  one  of  the  vessels  is  injured. 

Both  superficial  to  and  within  the  substance  of  the  gland  are  a  number 
of  lymph  nodes  which  receive  lymph  from  the  temporal  and  frontal 
regions  of  the  scalp,  the  eyelids,  and  root  of  the  nose,  the  external  auditory 
meatus,  and  perhaps  the  nasal  fossa?.  They  empty  into  the  deep  cervical 
nodes.  These  lymph  nodes  when  enlarged  form  one  variety  of  parotid 
tumor.  The  sources  from  which  they  derive  their  lymph  supply  should 
be  examined  for  the  presence  of  lesions,  in  diagnosticating  between 
lymphatic  enlargements  and  other  parotid  tumors.  Abscess  on  the 
surface  or  within  the  gland  may  be  due  to  an  inflammation  of  these 
nodes.  The  deep  parotid  nodes  are  found  especially  along  the  carotid 
artery  and  the  temporomaxillary  vein. 

Tumors  of  the  parotid  are  not  uncommon.  Mixed  tumors,  containing 
cartilaginous,  myxomatous,  and  fibrous  portions,  occur  quite  often 
among  them.  The  cartilage  is  derived  from  islands  of  embryonal  car- 
tilage, from  the  mandibular  arch,  enclosed  within  the  gland.  In  addition 
there  are  malignant  tumors  or  malignant  degeneration  of  benign  tumors. 
It  is  a  striking  fact  that  the  testes,  in  which  metastases  after  mumps  are 
quite  common,  are  also  one  of  the  few  other  soft  parts  where  cartilage 
occurs  in  tumors.  The  benign  tumors  are  often  encapsulated  and  involve 
only  a  portion  of  the  gland  so  that  their  extirpation  may  be  readily 
accomplished  and  the  facial  nerve,  perhaps  somewhat  displaced,  may  be 
spired  in  whole  or  in  part.  It  has  been  much  discussed  whether  the 
entire  gland  can  be  or  should  be  removed  when  involved  in  a  newgrowth, 
especially  a  malignant  one.  The  operation  is  difficult,  but  it  certainly 
can  and  should  be  done  if  the  tumor  is  confined  within  the  capsule  of  the 
gland.  It  is  to  be  expected  that  the  facial  nerve  must  be  sacrificed,  but 
I  lie  result  of  this,  I  have  found,  is  often  not  so  distressing  as  might  be 
expected.  The  external  carotid  and  external  jugular  are  tied  in  the 
earlier-  stages  of  the  operation,  for  the  bleeding  is  very  free  from  the  arterial 
branches,  including  the  temporal,  internal  maxillary,  posterior  auricular, 
and  transverse  facial  arteries  and  the  branches  supplying  the  gland. 
/  ions  over  the  parotid  for  minor  conditions  should  be  transverse,  so 
a    to  avoid  the  branches  of  the  facial  nerve. 

The  upper  and  lower  jaws  are  both  susceptible  to  phosphorus  necrosis 
amon;_r  those  who  work  with  phosphorus,  as  in  match  factories,  bul  it 
i-,  almost  confined  to  those  with  carious  teeth.    I  have  also  seen  il  in  ;m 


104  THE  HEAD  AND  NECK 

old  colored  man  who  took  phosphorus  internally  for  a  long  time  to  keep 
up  his  sexual  vigor.  There  is  usually  an  osteoplastic  periostitis  resulting 
in  the  production  of  osteophytes,  which  themselves  are  liable  to  necrose. 

The  Upper  Jaw  or  Maxilla. — The  upper  jaw  or  maxilla  is  supported  or 
buttressed  above  and  internally  by  the  articulation  with  the  frontal  and 
nasal  bones,  above  and  externally  by  the  vertical  portion  of  the  malar, 
behind  by  the  pterygoid  process,  externally  by  the  zygomatic  arch,  inter- 
nally by  the  articulation  with  the  opposite  maxilla  in  the  hard  palate. 
Thus  supported,  it  is  not  very  often  fractured  but  it  may  be  by  direct  or 
indirect  violence.  In  the  latter  manner  the  shock  is  usually  transmitted 
through  the  lower  jaw  as  in  a  fall  or  blow,  more  rarely  through  the  head 
while  the  chin  is  fixed,  sometimes  through  the  malar  bone,  which,  on 
account  of  its  density,  is  seldom  fractured,  but  may  be  driven  into  the 
upper  jaw.  Fracture  by  direct  violence  may  be  due  to  a  direct  injury 
over  a  circumscribed  area  or  to  the  violent  extraction  of  a  tooth.  The 
maxilla  is  partly  protected  from  direct  violence  by  the  prominence  of  the 
nose  internally  and  the  malar  bone  externally.  When  the  wall  of  the 
antrum  is  fractured  it  may  be  much  depressed,  depending  upon  the 
direction  and  degree  of  the  force.  Whether  it  is  depressed  or  not,  sub- 
cutaneous emphysema  may  occur,  and  is  increased  on  blowing  the  nose. 
In  other  cases  pain  referred  to  the  dental  or  infra-orbital  nerves  may 
lead  to  the  diagnosis.  In  more  than  one  case  my  attention  has  been 
called  to  a  fracture  through  the  infra-orbital  margin  and  canal  by  pain 
in  the  nerve. 

Although  the  maxilla  is  very  vascular,  yet  its  periosteum,  like  that  of 
the  skull,  is  not  likely  to  form  new  bone,  so  that  there  is  no  reproduction 
after  necrosis.  The  infra-orbital  margin  is  the  favorite  site  of  tuberculous 
periostitis  and  osteomyelitis  of  the  maxilla. 

The  fact  that  the  maxilla  is  connected  with  the  surrounding  bony  parts 
at  four  points  is  important  to  remember  in  its  excision,  which  is  under- 
taken in  case  of  malignant  tumors,  etc.  (1)  The  connection  with  the 
malar  bone  is  divided  by  a  wire  saw  passed  through  the  forepart  of 
the  sphenomaxillary  fissure  after  raising  the  periosteum  of  the  orbital 
floor.  (2)  The  nasal  process  and  orbital  surface  of  the  maxilla  are 
divided  by  the  bone  forceps  whose  blades  are  introduced  into  the  nasal 
fossa  and  the  orbit  below  the  tendo  oculi.  In  some  cases  most  of  the 
orbital  floor  may  be  left,  the  section  passing  just  behind  or  sometimes 
below  the  orbital  margin.  The  orbital  plate  may  often  be  best  divided 
by  a  fine  chisel.  (3)  The  hard  palate,  by  which  the  opposite  maxilla 
and  palate  bones  are  connected  together,  is  divided  by  a  saw  or  bone 
forceps  after  extracting  a  central  incisor  and  dividing  and  stripping  up 
the  mucoperiosteum  on  its  under  surface.  (4)  Its  connection  behind 
with  the  pterygoid  process  and  the  intervening  palate  bone,  as  well  as 
with  muscular  attachments  (external  pterygoid),  are  freed  by  twisting 
the  bone,  to  avoid  unnecessary  injury  to  the  branches  of  the  internal 
maxillary  artery.  Before  this  last  step  in  the  removal  of  the  jaw  it  is 
well  to  cut  the  infra-orbital  nerve  at  the  back  of  its  groove  in  the  floor 
of  the  orbit  and  to  divide  the  connection  of  the  soft  palate  with  the  back 


THE  FACE  105 

of  the  hard  palate  on  the  affected  side.  The  bony  connections  are  divided 
in  the  order  named. 

To  expose  the  maxilla  for  excision  the  soft  parts  are  divided  down  to 
the  bone  along  the  lower  margin  of  the  orbit  to  the  side  of  the  nose, 
thence  in  the  groove  between  the  nose  and  the  cheek  and  the  nose  and 
the  lip  to  the  ridge  on  the  side  of  the  filtrum  of  the  lip  and  down  this 
ridge  through  the  lip.  In  this  incision  the  following  nerve*  and  vessels 
are  cut  in  die  following  order  from  above  downward;  the  palpebral 
branches  of  the  infra-orbital  vessels  and  nerve,  angular  artery  and  vein, 
lateralis  nasi  vessels,  nasal  branches  of  the  infra-orbital  nerve,  and  the 
superior  coronary  vessels.  Several  small  branches  of  the  facial  nerve 
may  also  be  cut,  Notice  that  no  large  vessels  are  divided  in  the  soft 
parts,  and  the  same  may  be  said  of  the  bone  section,  though  the  operation 
may  appear  bloody  from  the  many  small  branches  divided.  The  attach- 
ment of  the  lateral  cartilages  of  the  nose  to  the  bone  are  divided,  to  open 
up  the  anterior  nasal  orifice.  The  ./fop  is  then  turned  back,  keeping  close 
to  the  bone  if  the  soft  parts  are  not  involved,  and  in  any  case  taking  care 
to  keep  the  facial  artery  and  vein  intact  in  the  flap  and  to  avoid  Stenson's 
duct.  The  latter  may  be  avoided  by  remembering  its  course  and 
dividing  the  mucous  membrane  close  to  the  gums  so  as  to  avoid  the  orifice 
of  the  duct,  4  mm.  from  this  point. 

The  division  of  the  mucous  membrane  may  be  left  toward  the  last  to 
avoid  the  flow  of  blood  into  the  mouth.  In  rare  cases,  but  not  as  a  rule, 
the  mucoperiosteum  of  the  palate  may  be  spared  by  dividing  it  close  to 
the  alveolar  margin,  stripping  it  up,  and  subsequently  suturing  it  to  the 
mucosa  of  the  cheek,  thus  roofing  over  the  oral  cavity.  The  skin  flap 
is  well  nourished  by  the  facial  and  transverse  facial  vessels  and  is  supplied 
by  the  facial  nerve.  The  scar  is  almost  imperceptible  in  time.  By 
stripping  up  the  periosteum  of  the  orbital  floor  the  contents  of  the  orbit  are 
spared,  but  the  origin  of  the  inferior  oblique  muscle  is  detached.  The 
attachments  of  the  lateral  expansions  of  the  orbital  aponeurosis,  form- 
ing the  suspensory  ligament  of  the  eyeball,  should  be  spared.  In 
dividing  the  nasal  process  of  the  maxilla  and  the  lacrymal  bone  the 
lacrymal  sac  or  the  nasal  duct  will  be  cut  across.  If  the  nasal  process 
is  removed  high  up  the  origin  of  the  tendo  oculi  is  included.  In  the  last 
step  of  twisting  off  the  maxilla  the  descending  palatine  artery  and  great 
palatine  nerve  are  severed.  In  some  cases  where  the  tumor  involves 
only  a  part  of  the  maxilla,  most  commonly  the  alveolar  process,  the 
excision  may  be  partial,  sparing  in  such  a  case  the  orbital  floor  and  margin. 

Again,  temporary  resection  of  the  maxilla  is  practised  to  gain  access 
in  the  nasopharynx,  to  remove  polypi  situated  there.  Partial  resection, 
sparing  either  the  orbital  plate  or  the  palate  and  alveolar  arch,  gives  a 
better  exposure  and  is  preferable.  In  Langenbeck's  temporary  resection 
the  alveolar  arch  and  palate  are  left  undisturbed,  the  section  passing 

into   the    nose    above    them;    the  connection     with     the    malar    hone    is 

levered  and,  after  another  horizontal  section  is  made  from  the  orbit  to 

the  qb  sal  fossa,  tin;  bone  flap,  only  attached  to  the  Dasal  bone,  is  turned 
inward  ;i-  on  ;i  hinge,  and  is  replaced  ;il  the  end  of  the  operation. 


106  THE  HEAD  AND  NECK 

The  Lower  Jaw  or  Mandible. — The  lower  jaw  or  mandible  is  more 
often  fractured  than  any  other  bone  of  the  face,  in  spite  of  its  density,  its 
free  mobility,  the  buffer-like  interarticular  cartilages,  and  its  horseshoe 
shape,  which  gives  it  increased  elasticity.  It  may  be  broken  by  direct  or 
indirect  violence.  In  the  latter  case  the  pressure  either  increases  or  flattens 
the  curve  until  it  gives  way,  usually  at  its  weakest  point  about  3  cm. 
(1^  in.)  from  the  symphysis,  where  the  presence  of  the  mental  foramen 
seems  to  cause  a  weakness.  It  is  more  often  fractured  by  direct  violence, 
and  in  this  case  also  most  often  where  it  is  weakest  near  the  symphysis. 
The  line  of  fracture  may  be  nearly  vertical,  especially  when  at  or  near  the 
symphysis,  or  more  oblique,  in  most  cases  of  fracture  farther  back. 

The  displacement  depends  upon  the  position  and  direction  of  the 
fracture  and  the  direction  of  the  force.  In  general  the  elevator  muscles 
attached  to  the  ramus  draw  the  posterior  fragment  upward,  forward,  and 
outward,  while  at  the  same  time  gravity  and  the  depressor  muscles, 
digastric,  mylohyoid,  and  geniohyoid,  draw  the  anterior  fragment  back- 
ward, downward,  and  inward.  In  case  of  a  fracture  of  the  ramus  itself 
the  muscles  attached  to  it  hold  the  fragments  together.  In  double  frac- 
tures, which  are  quite  common,  the  intermediate  fragment  may  be  dis- 
placed downward  and  backward.  The  displacement  in  fractures  of  the 
body  of  the  bone  is  usually  plainly  visible  in  the  difference  of  level  of  the 
teeth.  The  neck  of  the  condyle  is  occasionally  broken  on  one  or  both  sides 
by  direct  blows  or  blows  on  the  chin.  In  such  cases  the  condyle  may  be 
drawn  forward  by  the  external  pterygoid  and  the  lower  fragment  pulled 
upward  by  the  other  muscles  of  mastication.  I  have  seen  an  oblique 
fracture  of  the  ramus  running  from  behind  downward  and  forward  and 
separating  the  region  of  the  angle  from  the  rest  of  the  bone.  Fractures 
of  the  alveolar  process  are  common  in  connection  with  pulling  teeth. 

Although,  owing  to  the  firm  character  and  close  attachment  of  the 
gums  to  the  bone,  fractures  of  the  body  of  the  lower  jaw  are  almost 
always  compounded  in  the  mouth,  and  are  thus  exposed  to  bacterial 
infection,  these  fractures  generally  do  well  if  the  mouth  is  kept  clean  and 
they  are  kept  in  good  position.  This  we  may  accomplish  by  splinting  the 
lower  against  the  upper  jaw  by  the  pressure  of  bandages,  preferably  with 
an  interdental  splint  intervening.  A  fracture  posterior  to  the  mental 
foramen  may  injure  the  inferior  dental  nerve  so  as  to  be  very  painful  and 
sometimes  to  cause  anesthesia  of  the  lower  lip  and  chin,  supplied  by  its 
mental  branch.  The  nerve  escapes  injury  more  often  than  one  would 
suppose,  and  only  in  rare  instances  has  it  been  compressed  later  on  by 
the  callus. 

Speech  is  interfered  with  on  account  of  the  attachment  of  the  muscles 
of  the  tongue  and  the  floor  of  the  mouth  to  the  jaw.  If  the  attachment 
of  the  genioglossus  is  displaced  backward  in  a  fracture  on  either  side  of 
the  symphysis,  or  is  divided  in  excision  of  the  jaw,  some  trouble  may  be 
experienced  from  the  tongue  falling  backward  and  blocking  the  pharynx. 

The  lower  like  the  upper  jaw  may  be  the  seat  of  malignant  tumors, 
especially  sarcoma,  which,  as  well  as  extensive  necrosis,  may  call  for 
excision  of  half  of  the  jaw,  more  or  less.    Excision  of  the  entire  jaw  is 


THE  FACE  107 

rarely  required.  In  excising  half  of  the  mandible  an  incision  is  made 
down  to  bone  along  its  lower  border,  commencing  a  little  beyond  the 
median  line.  It  is  not  necessary  to  extend  it  up  the  back  of  the  ramus, 
and  if  this  is  done  it  should  not  extend  more  than  2  cm.  (f  in.)  for  fear  of 
wounding  the  facial  nerve  or  even  Stenson's  duct.  Except  in  large  tumors 
it  is  not  necessary  to  incise  vertically  through  the  lower  lip,  and  even  then 
not  through  the  vermilion  border. 

The  horizontal  incision  divides  the  facial  vessels  at  the  antero-inferior 
angle  of  the  masseter,  also  some  branches  of  the  facial  and  superficial 
cervical  nerves.  If  the  lip  is  incised  in  the  median  line  the  anastomoses 
between  the  inferior  coronary,  inferior  labial,  and  submental  vessels  of 
the  two  sides  are  divided.  The  bone  is  then  freed  of  its  muscular  attach- 
ments, keeping  close  to  the  bone.  Except  when  there  is  a  malignant 
growth,  which  has  reached  to  or  developed  from  the  surface,  the  jaw  may 
often  be  excised  subperiosteal^ ,  largely  by  blunt  dissection.  In  this  con- 
nection Tillaux  has  called  attention  to  the  importance  and  the  feasibility 
of  preserving  the  periosteum  covering  the  angle  and  adjoining  parts 
which  connect  together  the  attachments  of  the  masseter  and  internal 
pterygoid  muscles.  The  entire  jatv  has  been  reproduced  after  subperiosteal 
removal. 

It  is  sometimes  difficult,  even  with  much  depression,  to  free  the  attach- 
ment of  the  temporal  muscle  which,  it  should  be  remembered,  is  attached 
to  the  margins  and  the  inner  surface  of  the  coronoid  process.  In  such 
cases  the  latter  may  be  cut  off  with  the  bone  forceps  in  place  of  detaching 
the  muscle.  As  to  the  condyle  it  is  best  at  the  last  to  twist  it  off  instead 
of  cutting  the  capsule  and  the  insertion  of  the  external  pterygoid,  on 
account  of  the  danger  of  wounding  the  internal  maxillary  artery  as  it 
winds  around  the  neck  of  the  condyle.  The  inferior  dental  vessels  and 
nerve  and  their  mylohyoid  branches  are  of  course  divided  close  to  the 
inferior  dental  foramen.  In  large  tumors  care  should  also  be  taken  to 
avoid  the  salivary  glands,  the  external  carotid  artery,  the  temporomaxil- 
lary  vein  and  the  lingual  and  auriculotemporal  nerves.  Cysts  and  tumors 
of  the  jaws  may  also  develop  from  the  tooth  germs  (see  p.  114).  Ip  a 
central  sarcoma  or  other  tumor  pain  from  pressure  on  the  dental  nerves 
may  be  one  of  the  earliest  symptoms  noticed.  Congenitally  the  jaw  has 
in  rare  cases  been  cleft  at  the  symphysis,  incompletely  formed,  or  entirely 
;il)scnt,  depending  upon  defective  development  of  the  mandibular  arcli. 

Temporomandibular  Joint. — The  condyle  can  be  seen,  and  felt  as  a 
slight  'projection  immediately  in  front  of  the  tragus  of  the  ear,  from 
which  point  it  can  be  seen  and  felt  to  move  forward  and  downward  onto 
the  articular  eminence  when  the  month  is  widely  opened.  In  dislocation 
tin-  condyle  slips  forward  and  upward  from  the  eminence  into  the  zygo- 
matic In  »a.  The  depression  which  is  seen  and  felt,  in  placeof  the  normal 
projection,  in  front  of  the  tragus  is  a  valuable  sign  of  dislocation,  especially 
when  it  is  unilateral.    Tin-  bony  external  auditory  canal  is  immediately 

behind  the  joint,  and  in  falls  or  blows  on  tin;  chin   the  condyle  may  be 

driven  upward  through  the  glenoid  fossa,  fracturing  the  base  of  the  skull, 

or  backward,  fracturing  the  anterior  Wall  of  the  canal.     (  uilv  in  tin;  latter 


108  THE  HEAD  AND  NECK 

way  is  a  posterior  dislocation  possible.  The  direction  of  the  fibers  of  the 
only  strong  ligament  of  the  joint,  the  external  lateral,  is  downward  and 
backward,  so  that  it  resists  the  backward  movement  of  the  condyle  and 
thus  protects  the  wall  of  the  canal  from  more  frequent  injury. 

Dislocation  of  this  joint  is  permitted  in  the  forward  directly  only,  with 
the  above  exception.  It  occurs  only  when  the  mouth  is  widely  open,  in 
which  position  the  external  lateral  ligament  is  relaxed  and  the  condyle 
is  on  the  eminentia  articularis,  from  which  it  is  pulled  forward  by  the 
vigorous  contraction  of  the  external  pterygoid  in  violent  yawning,  laugh- 
ing or  vomiting,  in  dentists'  operations,  and  in  the  violent  introduction  of 
large  objects  into  the  mouth.  When  the  condyle  is  pulled  in  front  of  the 
articular  eminence  it  glides  upward  and  forward  along  the  inclined  sur- 
face in  front  of  the  eminence  and  is  pulled  up  by  the  elevator  muscles, 
especially  the  deep  posterior  vertical  fibers  of  the  masseter.  The  jaw, 
however,  cannot  be  closed,  but  is  held  widely  open,  and  the  fixity  of 
this  position  and  the  difficulty  of  reduction  is  explained  in  different  ways. 

1.  The  direction  of  the  fibers  of  the  external  lateral  ligament  is  reversed 
in  the  new  position  of  the  condyle,  and  the  attempt  to  close  the  jaw  now 
puts  this  ligament  on  the  stretch.  The  same  is  true  of  an  attempt  to  push 
the  jaw  backward,  for  it  has  to  pass  downward  to  pass  beneath  the 
articular  eminence.  A  downward  as  well  as  backward  pressure  is  necessary 
in  the  reduction  of  the  dislocation,  and  this  can  be  effected  with  the  least 
tension  and  resistance  of  the  external  ligament  if  the  jaw  is  at  first  kept 
widely  open,  or  even  opened  more  widely.  When  the  jaw  is  not  dislocated 
it  is  not  true,  however,  as  is  sometimes  stated,  that  the  external  lateral 
ligament  is  relaxed  when  the  mouth  is  wide  open,  but  rather  the  reverse, 
for  the  ligament  is  tightened  by  depression  of  the  jaw  and  by  the  down- 
ward gliding  onto  the  articular  eminence  more  than  it  is  relaxed  by  the 
forward  movement  of  the  condyle. 

2.  In  the  combined  hinge  and  sliding  movement  of  the  jaw  the  con- 
dyle moves  forward,  the  angle  backward,  and  the  axis  of  motion,  or  the 
part  which  moves  least,  is  about  the  centre  of  the  ramus,  or  at  the  inferior 
dental  foramen.  Hence  the  vessels  and  nerves  which  enter  this  foramen 
are  not  subject  to  traction  and  displacement,  as  they  otherwise  would  be. 
The  line  of  action  of  the  masseter  and  internal  pterygoid  muscles  normally 
passes  upward  and  forward  in  front  of  this  axis.  When,  however,  the 
jaw  is  dislocated  forward  the  line  of  action  of  these  muscles  is  displaced 
somewhat  backward  with  the  angle,  while  the  axis  of  motion  is  displaced 
in  front  of  it  (Fig.  39).  Hence,  while  normally  the  action  of  these 
muscles  is  to  elevate  the  front  of  the  jaw  and  depress  the  angle,  in  a  dis- 
located jaw  their  action  is  reversed  so  that  they  open  the  jaw  and  keep 
it  open.  That  the  muscles  are  spasmodically  contracted,  from  their  being 
injured  or  put  on  the  stretch  or  from  pressure  or  traction  on  their  nerves, 
can  be  readily  felt  on  the  patient.  According  to  Tillaux,  a  dislocation  is 
produced  when  in  a  violent  opening  of  the  mouth  the  axis  of  motion  is 
carried  in  front  of  the  line  of  muscular  action.  In  a  dislocation  the  con- 
dyle may  be  said  to  be  held  by  a  balance  of  forces  between  the  external 
lateral  ligament  pulling  upward  and  backward  and  the  muscles  pulling 


THE  FACE 


109 


upward  and  forward.  (3)  It  is  possible  in  rare  cases,  as  in  the  speci- 
men in  the  Musee  Dupuytren,  that  the  apex  of  an  unusually  long  coro- 
noid  process  may  be  caught  against  the  malar  bone  and  resist  reduction. 
The  fibrocartilage  may  occasionally  prevent  complete  reduction  by 
blocking  the  glenoid  cavity;  it  is  not  the  cause  of  the  fixation  of  the  jaw. 

In  dislocation  the  fibrocartilage  may,  in  rare  instances,  pass  forward 
with  the  condyle,  but  it  usually  remains  behind  in  the  glenoid  fossa,  and 
in  the  latter  case  the  anterior  part  of  the  capsule  may  be  torn.  The  dis- 
location may  occur  on  one  or  both  sides. 

The  lower  jaw  is  sometimes  held  firmly  closed.  This  may  be  due  to 
a  tonic  spasm  of  the  muscles  of  mastication,  a  condition  known  as 
trismus  or  lockjaw.    This  may  be  an  early  symptom  of  teianus  or  a  reflex 

Fig.  39 

direction  of  ext. 
lateral  ligament 


INTERARTIC. 
FIBRO- 
CARTILAGE 


LINE    OF    ACTION    OF 
ELEVATOR     MUSCLES 

AXIS    OF    MOVEMENT 
OF    DISLOCATED    JAW 

AXIS    OF    MOVEMENT 
OF   JAW 


I  igure  to  -how  the  relation  of  the  line  of  action  of  the  masseter  and  internal  pterygoid 
mnaclei  t<>  the  axis  of  movement  of  the  lower  jaw  in  its  normal  position  and  in  dislocation. 
The  dotted  line  represents  the  position  of  the  dislocated  jaw.      (Tillaux.) 

symptom  due  to  the  irritation  of  one  of  the  sensory  branches  of  the  fifth 
nerve,  especially  those  of  the  lower  teeth.  The  nerve  to  the  muscles 
which  close  the  jaw  is  the  only  motor  branch  derived  from  the  fifth  nerve. 
Again  the  firm  closure  of  the  jaw  may  be  due  to  a  cicatricial  contraction 
following  a  cancrum  oris  or  other  large  loss  of  substance  of  the  cheek 
or  to  ;m  ankylosis  of  the  temporomandibular  joint  from  rheumatic  or 
septic  (especially  gonorrheal)  synovitis.     In  ankylosis  an  excision  of  the 

neck  of  the  condyle  is  done  to  secure  ;i  false  joint. 

The  two  lips  unite  laterally  ;it   the  commissures  to  enclose  ;i   transverse 

aperture  {the  buccal  orifice)  popularly  culled  the  mouth,  bul  the  latter 

term  strictly  applies  to  the  cavity  to  which  the  opening  leads.    The  lips 

I  of  ihe  following  layers:  (1)  Skin  closely  adherent  to  (2)  ;i  mus- 


HO  THE  HEAD  AND  NECK 

cular  layer  (orbicularis  oris),  (3)  labial  mucous  glands  among  which  are 
the  coronary  vessels,  and  (4)  mucous  membrane. 

The  thick  skin  joins  the  mucous  membrane  along  the  free  border  by 
an  intervening  "vermilion  border,"  or  dry  mucous  membrane,  which  is 
remarkable  for  its  sensitiveness  and  the  frequent  occurrence  of  epithe- 
lioma at  the  line  of  junction,  especially  on  the  lower  lip.  The  color  of 
this  border  indicates  the  condition  of  the  blood  and  the  circulation,  save 
in  those  much  exposed  to  the  weather.  This  border  on  the  upper  lip 
presents  a  median  tubercle,  the  remains  of  the  free  extremity  of  the 
frontonasal  process.  From  this  tubercle  up  to  the  columna  nasi  is  a 
shallow  groove,  the  filtrum,  bounded  by  two  low  ridges,  along  which  verti- 
cal incisions  are  carried  if  it  is  desired  to  show  as  little  scar  as  possible. 

The  muscular  fibers  run  mostly  parallel  with  the  buccal  orifice,  hence 
incisions  to  open  abscesses,  etc.,  should  be  horizontal,  for  a  vertical 
incision  is  followed  by  considerable  retraction  of  the  edges.  Into  the 
orbicularis  oris  are  inserted  most  of  the  muscles  of  expression. 

The  glandular  layer  is  formed  of  racemose  glands  resembling  the 
salivary  glands.  It  may  hypertrophy,  as  a  whole,  thickening  the  lip, 
or  the  individual  glands  may  form  retention  cysts.  On  a  vertical  section 
of  the  lips  this  layer  protrudes,  while  the  muscular  layer  retracts.  The 
coronary  arteries  are  embedded  in  this  layer  close  beneath  the  mucosa 
and  nearer  the  free  than  the  attached  margin  of  the  lips,  about  12  mm. 
(^  in.)  from  the  former.  Bleeding  from  them  may  be  easily  prevented 
or  stopped  by  pressure  of  the  fingers  or  a  temporary  ligature.  In  suturing 
vertical  incisions  of  the  lip,  as  in  harelip  operations,  one  suture  should  be 
passed  behind  both  ends  of  the  artery,  between  it  and  the  mucosa,  to 
check  the  hemorrhage.  The  coronary  arteries  can  retract  freely  into  the 
loose  tissue  in  which  they  lie,  so  that  bleeding  is  often  spontaneously 
arrested.  As  the  superior  coronary  artery  sends  a  branch  to  the  septum 
nasi,  compression  of  the  artery  may  check  nose  bleed.  The  vascularity  of 
the  lips,  from  the  coronary  and  other  arteries,  accounts  for  the  frequent 
presence  of  nevi  and  other  vascular  tumors,  as  well  as  for  the  ready  healing 
of  the  many  plastic  operations  performed  to  relieve  deformities  and  fill 
the  gaps  left  by  the  removal  of  newgrowths  about  the  mouth.  The 
success  of  these  operations  is  also  favored  by  the  laxity  and  mobility  of 
the  tissues  about  the  mouth.  The  vessels  of  the  two  sides  of  the  lips 
anastomose  freely,  hence  both  ends  of  a  divided  vessel  should  be  tied. 
The  connection  of  the  veins,  through  the  facial  and  ophthalmic,  with  the 
cavernous  sinuses  should  be  remembered  in  inflammatory  conditions  of 
the  lips,  especially  the  upper  lip. 

The  lymphatics  pass  to  the  submaxillary  and  submental  nodes,  so  that 
these  nodes  may  be  involved  and  require  removal  in  epithelioma  of  the  lip. 
As  the  subcutaneous  lymphatics  of  the  two  sides  of  the  lower  lip  frequently 
cross  or  anastomose  across  the  median  line,  the  nodes  of  both  sides  are 
liable  to  be  infected.  The  nerves  of  the  upper  lip  come  from  the  second 
division  (infra-orbital),  those  of  the  lower  lip  from  the  third  division 
(inferior  dental)  of  the  fifth  nerve.  There  are  numerous  end  bulbs 
resembling  tactile  corpuscles  in  the  sensitive  vermilion  border.    In^the 


THE  FACE  HI 

distribution  of  the  labial  nerves,  from  the  second  and  third  divisions  of 
the  fifth  pair  of  nerves  for  the  upper  and  lower  lips  respectively,  a  crop  of 
herpes  (herpes  labialis)  often  appears,  of  neurotic  or  digestive  origin. 

The  mucous  membrane,  reflected  onto  the  gums  above  and  below,  at  the 
attached  margin  of  the  lips,  presents  on  each  lip  a  small  median  fold  or 
frenulum,  of  which  the  upper  is  the  larger.  In  extensive  plastic  opera- 
tions, as  after  the  removal  of  a  large  epithelioma  of  the  lip,  it  is  essential 
for  a  good  and  permanent  result  that  the  flap  should  be  lined  by  mucous 
membrane,  otherwise  it  becomes  adherent  to  the  jaw  and  immovable  and 
does  not  oppose  the  dribbling  of  saliva.  In  case  the  newgrowth  is  smaller 
a  V-shaped  incision  with  suture  of  the  edges  suffices. 

Development.— In  the  fetus  near  the  end  of  the  second  week  the  buccal 
and  nasal  cavities  are  one,  bounded  above  by  the  frontonasal  process, 
laterally  by  the  superior  maxillary  processes,  and  below  by  the  mandibular 
processes  of  the  first  visceral  arch.  These  two  cavities  are  separated  by 
the  fusion  of  the  median  frontonasal  and  the  laterally  placed  superior 
maxillary  processes  to  form  the  upper  lip  and  palate,  as  well  as  the  upper 
part  of  the  face. 

Fig.  40  Fig.  41 


Complete  lateral  harelip.    ■  Double  harelip. 

The  lower  lip  is  formed  by  the  median  fusion  of  the  coverings  of  the 
lateral  halves  of  the  mandibular  or  first  visceral  arch.  Failure  of  this 
fusion,  resulting  in  a  median  cleft  of  the  lower  lip,  is  very  rare  and  only 
a  few  instances  of  it  are  on  record. 

Failure  of  the  fusion  on  one  or  both  sides  of  the  frontonasal  process 
causes  single  or  double  harelip  respectively.  Hence  this  is  lateral  and 
not  median,  a  median  cleft,  like  that  of  the  hare,  being  very  rare  and 
otherwise  formed.  Harelip  is  more  often  single  and  on  the  left  side,  and 
is  commoner  in  males.  It  may  involve  part  of  the  lip  only  or  extend 
up  into  the  nostril.  In  the  latter  case  it  is  often  combined  with  a  cleft 
of  the  alveolar  arch  or  of  tin-  palate  as  well. 

In  double  harelip  the  central  insulated  part  of  the  lip  often  appears 

;i  -  ;i  nodule  attached  to  Or  suspended  from  the  nose,  for  it  is  protruded  by 

the  premaxillary  bone,  which  projects  forward  at  the  end  of  the  vomer. 
This  condition  is  due  to  the  facl  thai  the  premaxillary  bone,  the  septum 
of  tli<-  nose,  and  the  central  pari  of  the  lip  are  formed  by  the  frontonasal 
process.  In  single  harelip,  or  on  one  side  of  a  double  harelip,  there  may 
be  ;i  projection  of  the  alveolar  arch  on  the  median  side  of  the  cleft,  making 
it,  closure  more  difficult,  so  thai  this  projection  should  first  be  reduced. 


112  THE  HEAD  AND  NECK 

The  cure  of  harelip  by  plastic  operation  is  very  satisfactory.  The  two 
halves  of  the  lip  must  first  be  freed  from  the  maxilla,  to  which  they  are 
unusually  adherent,  the  edges  freshened  in  one  of  several  ways,  and  then 
sutured. 

Transverse  facial  clefts,  due  to  failure  of  fusion  of  the  mandibular 
arches  and  the  superior  maxillary  process,  commence  at  the  corners  of 
the  mouth  and  cause  an  enlargement  of  the  latter  {macro stoma).  The 
opposite  condition,  or  atresia  of  the  buccal  orifice,  occurs  when  the  fusion 
exceeds  the  normal  limits  or  it  follows  contraction  due  to  pathological 
processes,  such  as  burns,  or  faulty  plastic  operations.  It  may  also  be 
relieved  by  operation. 

When  the  jaws  are  closed  there  exists  between  them  and  the  cheeks 
and  lips  a  space  known  as  the  vestibule  of  the  mouth.  The  circumference 
of  this  space  is  bounded  by  the  reflection  of  the  mucous  membrane  from 
the  gums  to  the  cheeks  and  lips.  Through  this  reflection  we  may  incise 
to  expose  the  infra-orbital  and  mental  nerves  and  to  open  the  antrum, 
as  described  above.  It  is  near  this  line  of  reflection  that  we  find  the 
abscesses  which  are  developed  from  a  fistulous  tract  leading  from  a  dis- 
eased root  of  a  tooth.  Such  an  abscess  may  be  seen,  if  within  the  vesti- 
bule, or  felt  if  just  beyond.  At  the  back  of  the  vestibule,  behind  the  last 
molar,  is  a  space  usually  large  enough  for  the  passage  of  a  feeding  tube 
in  case  of  trismus;  and  in  addition  liquids  can  trickle  through  the  inter- 
stices between  the  teeth.  The  anterior  border  of  the  coronoid  process  can 
be  felt  plainly  at  the  back  of  the  vestibule.  In  dislocation  it  is  much  more 
appreciable,  and  its  prominence  may  be  an  aid  to  diagnosis.  In  addition, 
as  this  border  passes  down  onto  the  body  of  the  jaw,  external  to  the 
alveolar  process,  it  forms  a  kind  of  shelf  outside  of  the  last  molars,  on 
which  we  may  make  pressure  with  the  thumbs  in  reducing  a  dislocation 
of  the  jaw,  and  thus  avoid  the  danger  of  being  bitten  when  the  jaws 
close  with  a  snap  on  reduction.  The  duct  of  Stenson  opens  into  the  vesti- 
bule (see  p.  98). 

The  Gums. — The  gums,  formed  by  the  closely  united  mucous  mem- 
brane and  periosteum  covering  the  alveolar  processes,  are  dense,  firm,  and 
vascular,  though  paler  in  color  than  the  adjacent  mucosa.  As  the  peri- 
osteum of  the  gum  is  continuous  with  that  lining  the  sockets  of  the  teeth, 
inflammation  originating  in  the  socket  from  a  carious  tooth  may  extend 
up  and  out  of  the  socket  beneath  the  periosteum  and  form  a  subperiosteal 
alveolar  abscess  or  "gumboil."  The  latter  may  also  occur  more  super- 
ficially in  the  tissue  of  the  gums.  The  pain  is  considerable,  as  the  pus 
is  bound  down  by  the  dense  gums.  A  similar  inflammation  may  burrow 
through  the  bony  wall  of  the  socket  and  appear  beneath  the  gums  a  little 
farther  from  the  alveolar  margin  (see  above).  In  either  case  the  abscess 
may  open  or  be  opened  here  and  go  no  farther,  or  it  may  extend  widely 
beneath  the  periosteum  and  cause  a  necrosis  of  the  jaw.  If  the  end  of  the 
root  socket  of  a  tooth  is  beyond  the  limit  of  the  gums,  or  if  the  pus  can 
gravitate  beyond  it,  the  abscess  is  likely  to  break  through  into  the  cheek 
instead  of  through  the  gums.  Ulcerated  teeth  are  the  common  cause  of 
necrosis  of  the  jaws  and  should  be  suspected  in  case  of  swelling,  abscess, 


THE  FACE  113 

or  fistula  of  the  lower  face  and  submaxillary  region.  A  similar  inflam- 
mation in  the  sockets  of  the  upper  molars  may  spread  to  the  antrum  and 
be  the  cause  of  an  empyema  there. 

The  gums  covering  the  outer  and  inner  surfaces  of  the  alveolar  process 
are  continuous  in  the  interstices  between  the  teeth  and  are  normally 
closely  adherent  to  the  neck  of  the  teeth,  thereby  helping  to  hold  them  in, 
so  that  when  the  gums  are  detached  the  teeth  are  more  liable  to  become 
loose.  From  the  gums  are  developed  a  class  of  tumors  called  epulis,  which 
may  be  a  simple  fibroma  of  the  gums  or  a  sarcoma  developed  from  the 
periosteum.  The  latter  form  requires  the  removal  of  the  adjacent  portion 
of  the  alveolar  process  to  avoid  recurrence. 

In  old  age  as  in  infancy  the  gums  cover  the  upper  border  of  the  jaw;  in 
the  former  case  they  are  very  thick  and  hard,  so  as  to  allow  a  certain 
amount  of  mastication;  in  the  latter  case  they  may  become  much  inflamed 
and  cause  much  reflex  irritation  during  the  eruption  of  the  teeth,  so  as  to 
require  "lancing"  the  gums.  In  mercurial  poisoning  and  in  scurvy  the 
gums  are  characteristically  congested  and  spongy,  so  that  they  bleed 
readily  and  may  become  ulcerated.  Such  inflammation  of  the  gums 
(gingivitis)  may  spread  to  the  mucosa  of  the  entire  oral  cavity  (stomatitis). 
In  children  crowded  in  large  institutions  such  inflammation,  originating 
perhaps  in  the  lack  of  cleanliness  of  the  teeth  at  their  junction  with  the 
gums,  may  go  on  to  the  destruction  of  more  or  less  of  the  alveolar  process. 
In  chronic  lead  poisoning  a  blue  line  of  sulphide  of  lead  may  appear  along 
the  dental  margins  of  the  gums,  due,  it  is  said,  to  the  action  on  the  lead 
of  hydrogen  sulphide  formed  by  the  decomposition  of  food  debris  about 
the  teeth,  if  the  latter  are  not  kept  clean. 

The  Teeth. — It  is  impracticable  to  try  to  remember  the  time  of 
eruption  of  each  of  the  twenty  temporary  and  thirty-two  permanent  teeth. 
The  order  of  appearance  is  much  more  regular  than  the  exact  time,  which 
is  liable  to  much  variation.  The  temporary  teeth  appear  in  the  following 
order:  lower  central  incisors,  upper  incisors,  lower  lateral  incisors  and  the 
four  anterior  molars,  the  four  canines,  and,  finally,  the  four  posterior 
molars.  The  first  dentition  usually  begins  in  the  seventh  month  and  is 
completed  at  the  age  of  two  or  two  and  one-half  years.  The  lower  teeth 
;i])j)car  before  the  upper.  In  rare  instances  a  child  is  born  with  teeth. 
Syphilitic  children  are  rather  prone  to  early  dentition  and  early  decay 
of  t he  teeth.  Dentition  is  often  delayed  in  rickets  and  still  more  so  in 
cretinism,  and  it  may  be  said  to  go  on  in  a  manner  corresponding  to  the 
ficatioD  of  the  cranial  bones. 

In  the  permanent  set  a  similar  order  is  followed  except  that  the  first 
mol  -year  molars)  are  the  first  to  appear,  usually  in  the  seven  I  li 

year.  Tin-  second  molars  ( t  welve-year  molars)  appear  from  the  twelfth  to 
the  fifteenth  year,  the  third  molars,  or  wisdom  teeth,  from  the  seven- 
teenth to  the  twenty-fifth  year,  or  they  may  never  appeal-,  In  which 
<;i  e  they  may  lead  to  the  formation  of  cysts  of  the  jaw.  It  is  t<>  be 
noticed  in  both  <i  dmi  the  canine  teeth  appear  after  those  on  either  side 
of  them,  so  that  the  alveolar  arch  may  need  to  be  spread  to  make  room 
for  them. 


114  THE  HEAD  AND  NECK 

Certain  tumors  and  cysts  (odontomata)  of  the  jaws  are  produced  by 
aberrations  of  any  or  all  of  the  embryonic  parts  concerned  in  the  pro- 
duction of  a  tooth  at  any  stage  of  its  development  (Sutton).  They  form 
tumors  within  the  jaws  of  a  fibrous,  epithelial,  or  bony  structure,  accord- 
ing to  the  period  of  their  development  or  the  part  of  the  tooth  germ 
from  which  they  spring.  Odontomata  only  require  enucleation,  and  not 
resection  of  the  jaw. 

The  enamel  of  the  teeth  is  developed  from  the  epithelium  of  the  margin 
of  the  gums  which,  becoming  thickened,  dips  into  the  substance  of  the 
gums  as  the  "dental  shelf,"  and  forms  as  many  epithelial  caps  or  enamel 
organs  as  there  are  to  be  teeth  in  each  set.  Those  of  the  permanent  set 
lie  behind  those  of  the  temporary  set.  From  the  dental  shelf  or  enamel 
organs  are  formed  the  epithelial  odontomata.  The  rest  of  the  tooth  grows 
up  as  a  small  papilla  beneath  the  enamel  organ,  and  finally  becomes 
capped  by  it,  the  whole  being  enveloped  in  a  sac  (tooth  sac). 

The  incisor  teeth  of  the  permanent  set  present  certain  peculiarities  in 
many  children  having  hereditary  syphilis.  The  characteristic  or  "test 
teeth"  of  Hutchinson  are  the  upper  central  incisors  which  present  a  single 
crescentic  notch  in  the  centre  of  the  free  edge.  These  syphilitic  teeth 
are  often  short,  thick,  and  tapering.  The  teeth  of  the  upper  and  lower 
jaws  are  supplied  by  branches  of  the  second  and  third  divisions  of  the 
fifth  nerve  respectively,  and  irritation  of  these  nerve  endings,  as  in  dental 
caries  and  exposed  roots,  may  give  rise  to  reflex  facial  neuralgia  or  be 
the  starting  point  of  true  tic  douloureux. 

The  Floor  of  the  Mouth. — The  mylohyoid  muscle  forms  the  dia- 
phragm or  muscular  floor  of  the  mouth,  separating  the  buccal  cavity 
from  the  neck.  All  tumors  or  abscesses  developed  above  this  muscle  pro- 
ject or  point  into  the  buccal  cavity  and  may  be  operated  upon  by  that 
route;  while  those  developing  below  the  muscle  present  in  the  neck  and 
may  best  be  reached  through  an  incision  there. 

The  Tongue. — The  tongue  occupies  the  greater  part  of  the  floor  of 
the  mouth.  Between  the  interlacing  muscle  fibers,  of  which  the  tongue 
is  composed,  is  a  comparatively  small  amount  of  connective  tissue.  It 
is  noteworthy  that  cellulitis  or  inflammation  of  this  tissue  (glossitis)  is 
uncommon;  but  when  it  does  occur  the  tongue  may  swell  greatly  so  as 
to  threaten  asphyxia  by  pressing  down  the  epiglottis.  Owing  to  the  firm 
texture  of  the  tongue  and  its  thick  mucosa,  abscess  in  its  substance  feels 
like  a  solid  tumor.  Foreign  bodies  may  easily  become  embedded  in  the 
tongue. 

The  tongue  is  not  attached  or  anchored  by  ligaments,  but  by  its  extrinsic 
muscles,  to  the  mandible  by  the  genioglossi,  to  the  styloid  process  by 
the  styloglossi,  and  to  the  hyoid  bone.  Hence  in  anesthesia,  when  the 
muscles  become  relaxed,  the  tongue  is  liable  to  drop  back  by  its  own 
weight  and  press  down  the  epiglottis  so  as  to  close  the  opening  into  the 
larynx.  This  tendency  may  be  diminished  by  placing  the  patient's 
head  on  the  side,  so  that  gravity  does  not  tend  to  force  the  tongue  back- 
ward; or  it  may  be  counteracted  by  pulling  the  tongue  forward  either 
directly,  by  the  tongue  forceps,  or  indirectly,  by  protruding  the  jaw,  by 


THE  FACE 


11.") 


pressing  forward  behind  the  rami,  and  thereby  pulling  die  tongue  forward 
by  the  genioglossi. 

The  tongue  normally  overhangs  the  entrance  of  the  larynx,  thereby 
hiding  it;  hence  if  the  tongue  is  drawn  too  far  forward  it  exposes  the 
larynx  and  favors  the  passage  of  food  or  other  fluids  into  it.  Similarly, 
when,  in  operations  on  the  tongue  or  in  excision  of  the  forepart  of  the 
lower  jaw,  the  genioglossi  muscles  are  divided  the  tongue  is  liable  to 
drop  back  if  the  patient  lies  upon  his  back.  Hence  precautions  are 
taken  to  have  the  patient  lie  upon  the  side,  to  fasten  the  tongue  forward 
by  suturing  its  base  to  the  mental  region,  and  to  thread  the  tongue  with 
a  silk  suture,  whereby  it  may  be  pulled  forward  as  occasion  requires, 
until  adhesions  form  which  fasten  it  in  position. 


Fig.   12 


Under  nirface  of  the  tongue  and  the  sublingual  space,  showing  openings  of  salivary  ducts. 
The  mucosa  "f  the  left  side  is  partly  removed,  and  shows  the  ranine  artery  and  the  lingual 
nerve.      (Gerrish,  after  Te.itut.) 

The  tongue  is  also  connected  by  mucosa  with  the  alveolar  arch  and  by 
fold-,  of  mucous  membrane  with  the  epiglottis,  the  soft  palate  (enclosing 
the  palatoglossus  muscle),  and  the  back  of  the  symphysis  of  the  jaw. 
The  latter  is  ;i  median  fold  known  as  tli<-  frenum  linguae,  which  oormall) 
ends  some  distance  shorl  of  the  tip  of  ili<'  tongue.  In  pare  instances  this 
frenum  extends  to  tli<-  tip,  or  is  abnormally  short,  so  as  (<>  restrict  the 
movements  of  the  tongue.  This  condition  of  "tongue-tie"  may  prevent 
the  infant  from  sucking  well  or,  later  in  life, interfere  with  articulation 
and  necessitate  division  <>!'  the  frenum,  This  may  l><'  done  after  lifting 
the  tongue  by  the  fingers  or  the  back  end  of  h  grooved  director,  the 


116  THE  HEAD  AND  NECK 

notch  in  which  is  made  for  the  purpose.  In  such  cases  the  free  edge  of  the 
frenum  should  be  divided  close  to  the  jaw,  so  as  to  avoid  the  ranine  veins 
on  the  under  surface  of  the  tongue,  and  the  frenum  may  then  be  torn 
loose  as  much  as  required.  If  there  is  any  bleeding  in  such  cases  it  is 
encouraged  and  not  checked  by  the  infant's  nursing. 

The  ranine  veins  just  mentioned  are  plainly  seen  beneath  the  mucosa 
of  the  under  surface  of  the  tongue,  less  than  12  mm.  (^in.)  from  and  on 
either  side  of  the  frenum.  The  ranine  arteries  lie  a  little  more  laterally 
and  more  deeply  placed,  beneath  fringes  of  mucous  membrane  which 
converge  toward  the  tip. 

Surface  of  the  Tongue. — It  is  the  bright-red  color  of  the  fungiform 
papillae,  scattered  along  the  sides  and  tips  of  tlie  tongue,  contrasted  with 
the  coating  of  the  rest  of  the  tongue,  which  produces  the  so-called  "straw- 
berry tongue"  of  scarlet  fever.  The  coating  of  the  tongue  is  composed 
of  a  mixture  of  desquamated  epithelium,  food  debris,  and  bacteria. 
Behind  the  circumvallate  papillae  there  is  much  lymphoid  tissue  in  the 
mucous  membrane.  This  is  collected  into  rounded  masses  which  are 
sometimes  hypertrophied  to  form  an  irregular  nodular  mass  known  as 
the  lingual  tonsil,  which  may  require  removal  on  account  of  its  impairing 
the  movements  of  the  glottis  or  causing  an  irritating  cough.  The  foramen 
cecum  at  the  apex  of  the  circumvallate  papillae  represents  the  upper  end 
of  the  lingual  or  thyroglossal  duct.  In  connection  with  a  bilobed  mass  at 
the  lower  end  of  this  duct  the  greater  part  of  the  thyroid  gland  is  devel- 
oped. Except  in  rare  instances  the  thyroglossal  duct  disappears.  From  or 
contiguous  to  this  duct  there  occasionally  develops  a  tumor  of  the  base  of 
the  tongue  resembling  the  thyroid  gland  in  structure.  Mucous  cysts  are 
sometimes  developed  from  the  mucous  glands  which  abound  over  the 
posterior  third  of  the  tongue. 

The  surface  epithelium,  owing  to  chronic  irritation  or  inflammation, 
may  become  thickened  in  the  form  of  dense  opaque  plaques.  This 
condition,  variously  known  as  psoriasis,  or  ichthyosis  Ungues,  leukoma, 
and  smoker's  patch,  is  important,  as  it  may  develop  into  epithelioma, 
which  is  common  in  the  tongue,  especially  on  the  side  of  the  anterior  half. 
Tuberculous  or  syphilitic  ulcers,  which  also  occur  on  the  tongue,  may 
sometimes  be  mistaken  for  it. 

The  treatment  of  epithelioma  is  excision  of  the  tongue  by  one  of  the 
various  methods  employed,  through  the  mouth  or  from  beneath  the  jaw, 
and  with  or  without  previous  ligature  of  the  lingual  arteries  in  the  neck 
(see  p.  138).  In  operating  through  the  mouth  more  room  is  obtained  by 
stretching  the  mouth,  splitting  the  cheek,  or  dividing  the  jaw. 

Hemorrhage  is  the  chief  obstacle  in  operating  through  the  mouth.  It 
is  not  the  amount  but  the  locality  of  the  bleeding  and  the  danger  of  its 
running  back  into  the  larynx  and  trachea  that  concern  us.  Hence  the 
value  of  preliminary  ligature  of  the  Unguals  in  the  neck.  Some  bleeding 
still  occurs  on  the  stump,  especially  if  the  tongue  is  divided  far  back. 
This  comes  from  the  dorsalis  lingua  branches,  which  are  not  shut  off 
by  the  ligature,  and  from  small  anastomosing  vessels  of  the  ascending 
pharyngeal  and  the  tonsillar  branches  of  the  facial  arteries.    Bleeding 


THE  FACE  117 

from  the  stump  can  be  arrested  and  the  stump  brought  well  up  to  view 
by  pressing  up  the  floor  of  the  mouth  by  the  fingers  applied  between  the 
jaw  and  the  hyoid  bone.  If  the  operation  is  limited  to  one  side,  it  is  only 
necessary  to  ligate  the  lingual  on  that  side,  for  there  is  but  little  anasto- 
mosis across  the  rather  incomplete  median  fibrous  septum  of  the  tongue. 
The  two  ranine  arteries  anastomose  by  a  small  loop  near  the  tip  of  the 
tongue,  otherwise  only  by  capillary  branches,  except  in  the  rare  cases 
where  the  principal  part  of  both  linguals  is  given  off  from  one  side.  In 
the  latter  case  ligature  of  the  small  vessel  on  the  other  side  would  not 
prevent  copious  bleeding  on  that  side.  The  blood  may  be  prevented 
from  entering  the  larynx  (1)  by  the  position  of  the  head,  hanging  over 
the  end  of  the  table  (Rose's  position),  in  which  the  blood  accumulates 
in  the  upper  pharynx  and  escapes  from  the  nose  or  mouth,  which  are 
now  below  the  level  of  the  larynx,  or  (2)  by  giving  anesthesia  through 
tubes  passed  through  the  nose  into  the  lower  pharynx  and  packing  the 
oral  pharynx. 

The  following  structures  are  divided  in  an  excision  of  the  entire  tongue: 
the  mucous  membrane  connecting  the  tongue  with  the  jaw,  the  epiglottis, 
and  the  soft  palate;  the  genio-,  hyo-,  stylo-,  and  palatoglossi  and  the 
lingualis  muscles;  the  lingual,  hypoglossal,  and  glossopharyngeal  nerves, 
and  the  lingual  vessels  and  their  anastomoses  (see  above).  Excellent 
drainage  may  be  provided  through  an  opening  beneath  the  jaw  to  guard 
against  septic  aspiration  pneumonia,  a  not  infrequent  cause  of  death  in 
such  operations.  Wounds  of  the  tongue  are  not  uncommon  and  may 
require  suture.  I  have  seen  a  case  where  a  child  bit  her  tongue  half 
through,  and  a  similar  accident  had  occurred  in  two  previous  generations 
of  the  family. 

As  a  consequence  of  the  vascularity  of  the  tongue  it  may  be  the  seat  of 
nevoid  growths.  The  lingual  arteries  (averaging  3  mm.  (■$■  in.)  in  caliber) 
pass  upward  and  forward  to  the  base  of  the  tongue  beneath  the  hyo- 
glossus  muscle,  in  front  of  which  they  run  forward  as  the  ranine  arteries 
near  the  under  surface  of  the  tongue.  They  are  often  brittle,  especially 
at  the  age  when  cancer  is  prevalent.  Cancer  tends  to  extend  toward  the 
1  test  blood  supply,  hence  lingual  cancer  tends  to  spread  downward  toward 
the  root  of  the  tongue,  which  is  also  the  course  of  the  lymphatics.  The 
lymphatics  of  the  tongue  are  numerous  and  important  in  connection  with 
tin-  nodular  infection  which  occurs  early  in  lingual  cancer.  Some  of  the 
lymphatics  of  the  tip  of  the  tongue  enter  the  submental  nodes,  others  pass 
to  the  deep  cervical  node  just  above  the  point  where  the  omohyoid 
es  the  vessels.  The  lymphatics  from  the  rest  of  the  tongue  pass 
mostly  into  the  deep  cervical  nodes  lying  between  the  omohyoid  and 
trie  muscles,  especially  into  one  just  beneath  the  digastric,  while 
a  few  from  the  border  and  lateral  part  of  the  dorsum  pass  into  the  anterior 
submaxillary  nodes.  The  lymph  from  the  network  iii  the  vicinity  of  the 
circumvallate  papillse  may  be  carried  to  both  sides  of  the  neck,  and 
infection  may  follow  the  same  course  and  be  bilateral.  A  few  small 
nodes  may  lie  along  the  course  of  the  lymph  vessels  leading  from  the 
tongue  to  their  several  nodes.    The  enlargement  of  the  tongue  in  the 


118 


THE  HEAD  AND  NECK 


strange  congenital  condition  known  as  macroglossia  is  due  principally  to 
a  great  dilatation  of  the  lymph  channels  (lymphangioma)  and  to  an 
increase  of  the  lymphoid  tissue  throughout  the  tongue.  In  some  cases 
it  reaches  a  prodigious  size,  filling  and  projecting  far  out  of  the  mouth, 
and  deforming  the  teeth  and  alveolar  arches  by  pressing  them  forward. 
The  base  of  the  tongue  is  the  part  most  affected.  Excision  by  a  wedge- 
shaped  incision  or  the  use  of  the  cautery  sometimes  gives  a  good  result. 


Pig.  43 
vessels  from 
base  of  tongue 


MARGINAL  COL- 
LECTING TRUNKS 

TRUNKS  OF 


PRINCIPAL 
GLAND 


SUBMENTAL 


TRUNKS  OF 
MARGIN 


The  lymphatics  of  the  tongue;   anterior  view.      (Poirier  and  Charpy.) 

Nerves  of  the  Tongue. — The  hypoglossal  supplies  the  muscles  of  the 
tongue,  though  the  chorda  tympani  may  carry  some  motor  fibers  from 
the  facial.  The  chorda  tympani,  carrying  fibers  from  the  glossopharyn- 
geal nucleus  by  way  of  the  pars  intermedia,  supplies  taste  fibers  to 
the  anterior  two-thirds  of  the  tongue;  the  glossopharyngeal  nerve  sup- 
plies taste  and  sensory  fibers  to  its  posterior  third.  Branches  of  the 
superior  laryngeal  nerve  supply  sensation  to  the  root  of  the  tongue  just 


THE  FACE  110 

in  front  of  the  epiglottis.  The  lingual  or  gustatory  nerve  supplies  sensa- 
tion to  the  anterior  two-thirds  of  the  tongue,  in  which  the  sense  of  touch 
is  more  acute  than  in  any  other  part  of  the  body,  and  is  used  by  dealers  in 
precious  stones  when  the  eye  alone  cannot  be  trusted.  This  nerve  is  not 
infrequently  affected  by  neuralgia  or  responsible  for  reflex  symptoms  in 
other  branches  of  the  fifth  nerve,  such  as  "earache,"  "toothache," 
trismus,  etc.,  in  painful  affections  of  the  tongue,  which  are  most  common 
in  the  anterior  two-thirds  of  the  organ.  Neuralgia  of  this  nerve  in  cancer 
of  the  tongue  is  sometimes  so  severe  as  to  demand  its  division  or  excision. 
By  pulling  the  tongue  forward  and  to  the  opposite  side  the  nerve  may 
be  made  prominent  by  its  elevating  a  ridge  of  mucous  membrane  on  the 
floor  of  the  mouth,  between  the  tongue  and  the  alveolar  arch.  The 
nerve  may  be  excised  after  dividing  the  mucous  membrane  along  this 
ridge,  except  in  cases  where  the  tongue  is  much  enlarged  and  fixed  by 
cancer,  in  which  case  it  may  be  divided  by  a  bistoury,  entered  ajittleover 
12  mm.  (;j  in.)  behind  and  below  the  last  molar  down  to  bone,  cutting 
toward  the  tooth. 

After  the  lingual  nerve  has  passed  forward  from  between  the  ramus 
and  the  internal  pterygoid  muscle  it  runs  beneath  the  mucous  membrane, 
.">  mm.  (i  in.)  from  its  reflection  from  the  side  of  the  tongue  and  then 
beneath  the  sublingual  gland,  with  Wharton's  duct.  It  can  be  readily 
felt  by  the  finger  pressed  against  the  inner  surface  of  the  jaw  in  a  direction 
downward  and  backward  from  the  last  molar  tooth. 

The  part  of  the  floor  of  the  mouth  between  the  tongue  and  the  alveolar 
arch  is  covered  by  mucous  membrane,  reflected  from  the  tongue  to  the 
gums,  and  is  divided  into  two  symmetrical  halves  by  the  frenum  of  the 
tongue.  On  either  side  of  the  latter  is  a  well-marked  ridge,  directed 
backward  and  outwaid,  due  to  the  presence  of  the  sublingual  gland. 
Along  each  ridge  the  ten  to  twenty  ducts  of  the  gland  open,  and  at  the 
anterior  ends  of  the  ridge,  on  either  side  of  the  frenum,  we  notice  the 
papilla  on  which  is  the  orifice  of  Wharton's  duct.  The  duct  of  Bartholin, 
from  a  group  of  lobes  of  the  sublingual  gland,  opens  with  or  near 
Wharton's  duct. 

Wharton's  duct  passes  obliquely  forward  and  inward  for  5  cm.  (2  in.) 
from  the  deep  process  of  .the  submaxillary  gland,  near  the  posterior 
border  of  the  mylohyoid.  It  accompanies  the  lingual  uerre,  crossing 
above  the  latter,  which  inclines  inward  to  the  tongue,  and  it  lies  beneath 
and  behind,  or  internal  to,  the  sublingual  gland.     Its  walls  are  thin  but 

tmi  distensible,  so  that  when  it  becomes  blocked  by  an  impacted  calculus 
the  pain  from  tension  is  intense,  as  it  cannot  become  rapidly  or  largely 

dilated  to  form  a  cystic  luinor. 

Such  a  cystic  tumor  is  known  as  a  ranula,  a  term  applied  to  cysts  of 
varied  origin  filled  with  mucoid  contents  and  situated  under  (he  tongue 
or  in   (In-  floor  of  the  mouth.     Typical   ranula   is  a   retention  cyst  of  the 

mucous  glands;  according  to  Recklinghausen  most  frequently  of  those 

that  lie  beneath  the  tip  of  die  tongue.     (  )ther  cysts  in  this  situation  are 
ed  ■■<     ranula,  including  retention  cysts  of  the  sublingual  gland  duels 
or  of  Wharton's  duct. 


120  THE  HEAD  AND  NECK 

The  presence  of  Fleischmann's  sublingual  bursa  is  denied  by  most 
authorities,  but  according  to  Tillaux  it  is  the  seat  of  the  acute  or  rapidly 
formed  ranula,  which  sometimes  occurs.  Tillaux  describes  it  as  follows. 
It  is  triangular  in  form,  situated  between  the  genioglossus  muscle  and  the 
mucous  membrane  which  is  reflected  from  beneath  the  front  and  sides 
of  the  tongue  to  the  floor  of  the  mouth.  Its  apex  lies  at  the  end  of  the 
frenum  on  the  under  surface  of  the  tongue  and  its  base  at  the  sublingual 
gland,  which  separates  the  mucosa  from  the  genioglossus  muscle.  It  is 
constricted  in  its  centre  by  the  frenum  and  reaches  back  on  either  side 
to  the  first  or  second  molar  tooth.  Incision  alone  will  not  cure  a  ranula, 
for  after  the  incision  heals  the  cyst  refills.  Its  lining  membrane  must  be 
dissected  out  as  far  as  possible  and  the  remainder  cauterized. 

Congenital  dermoid  or  branchio genie  cysts  in  the  floor  of  the  mouth, 
between  the  tongue  and  the  lower  jaw,  may  resemble  ranula.  They 
are  due  to  the  imperfect  closure  of  the  first  visceral  cleft  or  arch.  Cysts 
or  solid  tumors  deeply  seated  in  the  tongue  or  in  the  vicinity  of  the  hyoid 
bone  may  develop  from  the  thyroglossal  duct,  leading  from  the  foramen 
cecum.  In  this  manner  probably  some  of  the  deep-seated  forms  of 
cancer  and  cancerous  cysts  of  the  neck  are  formed. 

The  loose  connective  tissue  in  the  floor  of  the  mouth  between  the  mylo- 
hyoid muscle  and  the  mucous  membrane,  and  secondarily  that  in  the 
submaxillary  region,  is  involved  in  the  septic  phlegmonous  inflammation 
known  as  Ludwig's  angina. 

The  Palate. — The  Hard  Palate. — The  hard  palate  separates  the  mouth 
from  the  nose,  so  that  when  it  is  cleft  these  two  cavities  communicate. 
Its  form  is  determined  by  that  of  the  horseshoe-shaped  alveolar  arch 
which  borders  it.  Normally  the  greatest  width  about  equals  its  length, 
but  this  relation  varies  widely.  Normally  it  presents  a  flat  arch,  abnor- 
mally a  high  and  narrow  one.  The  latter  form  is  said  to  be  common 
in  congenital  idiots  and  often  occurs  in  the  two  halves  of  a  cleft  palate, 
especially  in  complete  clefts.  This  is  a  fact  of  importance  in  the  closure 
of  the  cleft,  for  in  such  cases  the  flaps,  when  brought  down  to  a  more 
horizontal  position,  are  ample  to  meet  and  be  sutured  in  the  median  line. 
These  flaps  consist  of  the  entire  soft  parts  which  cover  the  bone  and  are 
composed  of  a  firm  pale  mucosa  fused  with  the  periosteum  so  that  they 
cannot  be  separated.  This  dense,  tough  mucoperiosteum  is  thickened  by 
the  many  glands  which  are  contained  between  its  two  layers,  except  in 
the  median  line.  Posterior  to  the  anterior  palatine  foramen  a  median 
raphe"  indicates  the  formation  of  the  palate  from  two  lateral  halves. 

The  mucoperiosteum  is  supplied  principally  by  the  posterior  palatine 
artery,  which  lies  near  its  deep  surface  and  passes  forward,  close  to  the 
junction  of  the  palate  and  the  alveolar  process,  from  the  lower  opening 
of  the  posterior  palatine  canal,  internal  to  the  last  molar  tooth  and  about 
8  mm.  (^  in.)  in  front  of  the  hamular  process.  The  two  principal  dangers 
of  operations  for  the  closure  of  a  cleft  of  the  hard  palate  are  hemorrhage 
and  gangrene  of  the  flaps,  both  due  to  a  division  of  the  posterior  palatine 
artery  or  its  branches  which  pass  inward  to  supply  the  mucoperiosteum. 
Hence  this  division  should  be  avoided,  and  the  artery  and  its  branches 


THE  FACE  121 

preserved  in  the  flap  for  its  nourishment,  by  making  the  lateral  incision, 
bordering  the  flap,  along  the  base  of  the  alveolar  process,  outside  the 
course  of  the  artery.    The  nerves  come  from  Meckel's  gang-lion. 

The  Soft  Palate. — The  soft  palate  is  of  about  the  same  length  as  the  hard 
palate,  but  it  is  broader  than  it  is  long,  and  about  6  mm.  (^  in.)  thick. 
Its  sides  are  merged  into  the  pharyngeal  wall.  The  anterior  third  of  the 
soft  palate  contains  the  palate  aponeurosis,  which  is  always  firm  and  tense, 
so  that,  as  it  is  continuous  in  position  and  direction  with  the  hard  palate, 
it  is  not  easy  to  distinguish  it  from  the  latter  by  the  touch,  as  in  passing 
a  Eustachian  catheter  (see  p.  64).  The  aponeurotic  portion  does  not 
share  in  the  movements  of  the  posterior  or  muscular  portion  of  the  soft 
palate.  The  tendon  of  the  tensor  palati  muscle  is  connected  with  this 
aponeurosis,  which  is  already  tense  and  can  scarcely  be  made  much  more 
so.  Indeed,  it  is  probable  that  the  principal  action  of  this  muscle,  cer- 
tainly of  those  fibers  attached  to  the  fibrous  portion  of  the  Eustachian 
tube,  is  to  open  that  tube.  Such  an  opening  occurs  whenever  the  palate 
is  raised,  as  in  swallowing,  and  on  this  fact  depends  the  Politzer  method 
of  inflating  the  middle  ear  (see  p.  64). 

The  fibers  of  the  palatoglossus  form  the  most  inferior  layer  of  those 
which  make  up  the  substance  of  the  soft  palate.  All  the  muscles  of 
the  palate  join  those  of  the  opposite  side  in  the  median  line,  and  hence, 
with  the  exception  of  the  azygos  uvula?,  by  their  contraction  tend 
to  widen  a  cleft  of  the  palate  or  pull  it  apart  when  sutured.  Accord- 
ing to  some  the  levator  and  tensor  palati  are  the  chief  agents  drawing 
asunder  the  sutured  cleft.  To  prevent  this  interference  with  the  success 
of  the  operation  many  have  employed  free  anteroposterior  incisions 
through  the  palate  along  the  side  of  each  half,  to  divide  the  muscles,  or  a 
tenotomy  of  one  or  more  muscles,  especially  the  levator  palati  and  palato- 
pharyngeus.  Billroth  broke  off  the  hamidar  process  and  displaced  it 
inward,  together  with  the  tensor  palati  tendon  which  winds  around  it, 
in  order  to  relax  the  latter,  with  good  results.  The  hamular  process  can 
be  felt  to  the  inner  side  and  behind  the  last  upper  molar  tooth.  Others 
use  various  forms  of  tension  sutures  and  plates.  Wolff  thinks  the  soft 
palate  is  best  relaxed  by  separating  the  mucoperiosteum  from  the  bony 
hard  palate,  as  in  operations  to  close  clefts  of  the  latter.  In  any  case  the 
aponeurosis  must  be  freed  from  its  attachment  to  the  posterior  border 
of  the  bony  palate,  to  allow  the  anterior  part  of  the  soft  palate  to  come 
together  readily. 

Tile  posterior  two-thirds  of  the  soft  palate,  the  portion  behind  its 
aponeurosis,  forms  the  velum  pendulum  palati  proper,  or  the  movable 
curtain  which  in  breathing  through  the  nose  hangs  down  in  the  isthmus 
of  the  f;n  ice-  and  shuts  oil'  the  mouth  from  the  pharynx,  and  in  deglutition 

or  breathing  through  the  month  is  raised  to  a  horizontal  position  to  shut 
oil'  the  buccal  portion  of  the  pharynx  from  the  nasopharynx,  to  prevent 
food  entering  the  latter  in  swallowing.     Hence  in  parahjsis  of  the  palate, 

ometimes  occur,  after  diphtheria  ami  from  other  causes,  the  palate 
cannot  !><•  raised,  the  na  jopharynx  is  not  shut  off,  and  fluids  are  liable  to 
regurgitate  through  the  nose.    The  elevation  of  the  palate  during  breath- 


J  22  THE  HEAD  AND  NECK 

ing  through  the  mouth  is  taken  advantage  of  in  one  form  of  nasal  irri- 
gation (see  p.  87).  When  the  palate  is  elevated  it  is  enabled  to  shut  off 
the  buccal  from  the  nasal  portion  of  the  pharynx  by  the  contraction  of  the 
superior  constrictor  muscle  which  narrows  this  part  of  the  pharynx  and 
brings  forward  its  posterior  wall. 

The  azygos  uvulae  passes  into  the  uvula  and  by  its  contraction  shortens 
and  raises  it.  Elongation  of  the  uvula  is  largely  due  to  hypertrophy  of 
the  part  near  the  tip,  beyond  the  muscle.  When  elongated  it  may  touch 
the  base  of  the  tongue  or  produce  coughing  in  the  supine  position  by 
irritating  the  back  wall  of  the  pharynx.  It  may  be  readily  snipped  off 
if  necessary.  From  the  base  of  the  uvula  two  folds  of  mucous  membrane 
pass  off  on  either  side  in  an  outward  and  downward  direction,  the  ante- 
rior and  posterior  pillars  of  the  fauces.  The  anterior  folds  cover  the  palato- 
glossi  and  incline  somewhat  forward.  The  posterior  folds  cover  the 
palatopharyngei  and  incline  somewhat  backward.  As  the  latter  approach 
nearer  to  one  another  than  the  anterior  pillars,  they  are  readily  seen 
behind  them.  Between  the  two  pillars  of  each  side  lie  the  tonsils  (see 
p.  124).  The  space  between  them  forms  the  isthmus  of  the  fauces,  the 
opening  between  the  mouth  and  the  pharynx,  which  is  bounded  by  the 
tongue  below  and  by  the  palate  above.  In  deglutition,  after  the  food  is 
passed  into  the  pharynx,  the  isthmus  is  closed  by  the  contraction  and 
approximation  of  its  pillars  and  the  elevation  of  the  back  of  the  tongue 
to  the  palate,  to  shut  off  the  mouth  from  the  pharynx. 

The  blood  supply  of  the  soft  palate  is  derived  from  the  ascending 
palatine  branch  of  the  facial,  the  palatine  branch  of  the  ascending  pharyn- 
geal artery,  and  the  descending  palatine  branch  of  the  internal  maxillary. 
The  lymphatics  of  the  lower  surface  of  the  palate  enter  the  deep  cervical 
nodes  along  the  jugular  vein  just  beneath  the  digastric.  Some  of  those 
of  the  upper  surface  enter  the  retropharyngeal  nodes.  The  sensory 
nerves  come  from  Meckel's  ganglion  and  the  glossopharyngeal.  The 
latter  nerve  probably  supplies  the  scattered  taste  buds  found  on  the 
under  surface  of  the  palate.  The  terms  palatable,  to  tickle  the  palate, 
etc.,  are  not  without  physiological  foundation  in  fact,  though  the  tongue 
is  the  principal  organ  of  taste. 

Development  (see  also  p.  111). — The  palate  is  formed  by  the  junction 
in  the  middle  line  of  the  palatal  plates  of  the  maxillary  processes  which 
grow  backward  and  inward  to  separate  the  mouth  from  the  nose.  This 
union  begins  in  front  about  the  eighth  week  of  fetal  life  and  is  completed 
posteriorly  in  the  ninth  and  tenth  weeks.  Throughout  the  hard  palate 
this  line  of  union  is  joined  from  above  by  the  frontonasal  process,  form- 
ing the  septum  of  the  nose,  to  the  lower  and  anterior  angle  of  which  are 
attached  the  premaxillary  bones.  These  bones  join  the  palate  processes 
of  the  maxillae  along  suture  lines  passing  forward  and  outward  from  the 
anterior  palatine  foramen  to  the  interspace  between  the  canine  and 
lateral  incisors  of  each  side,  so  that  they  contain  the  four  incisor  teeth. 

Congenital  cleft  palate  is  an  error  of  development,  a  failure  of  fusion 
of  the  parts  of  which  the  palate  is  formed.  In  the  soft  palate  the  cleft 
is  median  and  single;  in  the  hard  palate,  as  far  forward  as  the  anterior 


THE  FACE 


123 


Fig.  44 


palatine  foramen,  it  is  nearly  or  quite  median  in  position,  but  is  called 
unilateral  or  bilateral  according  as  one  or  both  palatal  processes  fail  to 
join  the  vomer.  If  the  cleft  is  unilateral,  it  communicates  with  the  nasal 
fossa  of  one  side;  if  bilateral,  with  both  nasal  fossa3,  and  the  free  border 
of  the  vomer  appears  in  or  above  the  cleft.  In  one  case  I  observed  entire 
absence  of  the  nasal  septum,  which  occurs  occasionally.  In  front  of  the 
anterior  palatine  foramen  the  cleft,  in  extending  through  the  alveolar 
border,  is  always  unilateral  or  bilateral,  never  median.  If  the  cleft  is 
bilateral,  the  premaxillary  hones  are  entirely  separate  from  the  maxilla\ 
and,  supported  on  the  end  of  the  nasal  septum,  they  often  protrude 
forward  and  appear  to  be  suspended  from  the  end  of  or  beneath  the  nose. 
Such  bilateral  clefts  are  usually  associated  with  a  double  harelip,  a 
unilateral  cleft  with  a  single  hare- 
lip.  In  unilateral  clefts  the  alveolar 
process  of  the  premaxillary  bones 
may  be  on  a  line  with  the  alveolar 
process  across  the  cleft,  or  it  may 
project  in  front  of  it. 

According  to  Ktilliker  and  others, 
the  cleft  in  the  lip  and  alveolar  pro- 
cess is  between  the  frontonasal  and 
the  maxillary  process,  i.  e.,  between 
the  premaxillary  bones  and  the  max- 
illa or  between  the  lateral  incisor  and 
canine  teeth.  But  Albrecht  regards 
it  as  between  the  frontonasal  and  the 
lateral  nasal  processes,  assuming 
four  premaxillary  bones,  two  on 
either  side,  and  claiming  that  the 
cleft  is  between  the  central  and 
lateral  incisors.  Both  views  are 
probably  correct,  and  the  position 
of  the  clefts  is  not  always  constant; 
some  are  between  the  lateral  incisor 
and  canine  teeth,  others  between  the 

lateral  and  central  incisors,  but  more  often  the  lateral  incisor  is  wanting. 
Tlie  protruded  premaxillary  bones  in  bilateral  elel'ts  contain,  as  a  rule, 
the  germs  of  the  central  incisors  only. 

Clef!  palate  varies  greatly  in  extent.    Rarely  it  may  involve  the  uvula 

only  or  merely  the  middle  of  the  soft  palate.  A  clef!  of  the  soft  pillule 
often  exists  without  any  in  the  hard  palate,  or  at  most  only  in  the  pos- 
terior pari  of  it ;  but  elel'ts  of  the  hard  palate  rarely  occur  without  one  in 
.ft  palate.  In  rare  cases  the  premaxillary  bones  may  be  entirely 
absent,  and  the  co-existing  double  harelip  shows  b  large  median  gap. 

The  usual  operation  consists  in  broadly  freshening  both  edges,  dissect- 
ing up  a  flap  of  mucoveriosteum  on  each  side  as  far  as  the  alveolar  process, 
where  it  is  limited  by  an  incision  along  the  base  of  the  process  (p.  120), 
and  then  bringing  together  and  suturing  the  edges.     In  infants  under 


Left-sided  harelip  and  cleft  palate. 
Marked  displacement  of  intermaxillary  bone. 
Boy,  aged  six  years. 


124  THE  HEAD  AND  NECK 

three  months,  and  possibly  up  to  six  months,  the  cleft  may  be  closed  by 
Brophy's  method,  forcibly  pressing  the  two  maxillae  together  and  holding 
them  by  two  transverse  wires  passed  through  and  fastened  over  lead 
plates  on  the  outer  surfaces  of  the  alveolar  processes.  It  seems  better  to 
treat  some  bad  clefts  of  the  palate  by  an  obturator  fastened  to  the  six-year 
molars.  Such  obturators,  if  well  made,  give  an  excellent  functional 
result  as  far  as  speech  and  swallowing  are  concerned.  Infants  with  cleft 
palate  can  usually  nurse  from  a  bottle  if  a  large  nipple  is  used  which  fills 
up  the  cleft.  But  later  on  articulation  is  very  imperfect  and  the  voice 
very  nasal  in  tone. 

The  Tonsils. — The  tonsils  are  masses  of  lymphoid  tissue  covered  with 
mucous  membrane  and  situated  in  the  triangular  recesses  between  the 
pillars  of  the  fauces  and  the  base  of  the  tongue.  The  floor  of  this  recess 
is  formed  by  the  pharyngeal  aponeurosis  and  the  superior  constrictor 
muscle,  on  which  each  tonsil  rests  and  by  which  it  is  separated  from 
the  pharyngomaxillary  space.  The  latter  lies  between  the  lateral  wall  of 
the  pharynx  internally,  the  internal  pterygoid  muscle  externally,  and  the 
upper  cervical  vertebras  posteriorly,  and  contains  fat  and  loose  cellular 
tissue.  Zuckerkandl  showed  that  it  was  divided  by  the  styloglossus  and 
stylopharyngeus  muscles  into  an  anterior  chamber,  contiguous  to  the 
tonsil,  and  a  posterior  chamber  containing  in  its  hindermost  part  the 
internal  carotid  artery  the  internal  jugular  vein  and  their  accompanying 
nerves  (Fig.  46). 

Quinsy,  which  is  a  peritonsillitis,  or  an  inflammation  around  the  tonsil, 
is  confined  in  most  cases  to  the  anterior  chamber  of  this  space,  and  only 
rarely  extends  to  the  posterior  chamber,  in  which  case  the  internal  carotid 
might  possibly  become  eroded,  as  reported  in  a  few  cases.  The  peri- 
tonsillar inflammation  in  the  anterior  chamber  meets  no  obstacle  in 
extending  outward  as  far  as  the  internal  pterygoid  muscle,  but  then 
further  swelling  projects  inward  toward  the  mouth  in  the  line  of  least 
resistance. 

A  quinsy  is  usually  opened  through  the  soft  palate  just  above  the  tonsil 
by  an  incision  parallel  with  the  anterior  faucial  pillar.  Wounding  the 
internal  carotid  is  out  of  the  question,  for  in  the  adult  it  lies  3  cm.  (1^-in.) 
behind  this  point  in  the  normal  state  and  probably  twice  as  far  when  the 
parts  are  bulged  forward  by  the  inflammation.  In  children  the  distance  is 
relatively  even  greater,  though,  of  course,  actually  somewhat  less.  As  the 
internal  carotid  is  about  2  cm.  (-|  in.)  behind  the  tonsil,  there  is  even  less 
danger  of  its  being  wounded  in  tonsillotomy,  for  no  puncture  is  then  made. 
A  wound  of  the  artery  has  probably  never  occurred  from  tonsillotomy  or 
opening  a  peritonsillar  abscess,  though  several  cases  are  recorded  where 
the  artery  has  become  eroded  in  a  peritonsillar  inflammation.  It  is  in 
operations  on  the  lateral  aspect  of  the  pharynx  that  the  internal  carotid 
is  in  danger  of  being  wounded. 

The  external  carotid  artery,  2  cm.  (■§•  in.)  from  the  lateral  periphery  of 
the  tonsil,  though  equally  near,  is  still  more  out  of  the  way,  lying  external 
to  the  muscles  arising  from  the  styloid  process.  The  ascending  pharyn- 
geal artery  is  nearer  the  tonsil  than  the  internal  carotid,  and  gives  a  branch 


PLATE  V 


ANTERIOR     PALA- 
TINE    FOSSA 


PREMAXILLARY 
SUTURE 


POSITION    OF    LATERAt 
CLEFT    OF    HARD 
PALATE 


DESCENDING    PALA- 
TINE   ARTERY 


Hard   Palate,  showing  the  course  of  the   arteries  and  of  a 
lateral  cleft.       (Modified  from  Merkel.) 


FIG.  46 


INT.   JUGU- 
LAR   VEIN     INT.    CAROTID 
ARTERY 


LONGUS    COLLI 
MUSCLE 


TEMP-MAXILLARY    VEIN 

PAROTID 

EXT.    CAROTID    ARTERY 

STYLO-HYOID  &.  STYLO- 

PHARYNG.    MUSCLES 

PHARYNGO-MAXILLARY 

SPACE 

NT.    PTERYGOID     MUSC. 
NF      DENTAL    FORAMEN 


MASSETER 


FACIAL    ARTERY 


LYMPH     NODE 

PALATO-PHARYNGEUS 

MUSCLE 
SUP.    CONSTRICTOR 
TONSIL 
PALATO-GLOSSUS 

MUSCLE 
FORAMEN    C/ECUM 


M 


Horizontal    Section  through  the  Commissure  of  the  Lips 
and    the  Tonsils.     (Merkel.) 


trough  the  odontoid  proce    ,  and    how     the  pharyngomaxillarj  space. 


THE  FACE  125 

to  it,  but  lies  behind  it  in  the  pharyngomaxillary  space,  and  its  main 
trunk  is  not  exposed  to  injury  in  tonsillotomy.  In  one  of  the  very  few 
cases  where  fatal  bleeding  followed  this  operation  the  tonsillar  branch 
of  the  facial  was  proved  to  be  the  source  of  hemorrhage.  Bleeding  from 
the  ascending  pharyngeal  artery  has  proved  fatal  in  a  case  reported  by 
Mr.  Morrant  Baker,  but  it  did  not  follow  tonsillotomy,  but  a  wound  due 
to  a  pipestem  driven  through  the  tonsil.  According  to  Merkel,  the  source 
of  severe  arterial  hemorrhage  after  tonsillotomy,  etc.,  is  in  most  cases  the 
facial  artery,  which,  as  it  passes  between  the  digastric  and  styloglossus 
muscles,  may  take  a  sharp  S-shaped  bend,  which  comes  very  close  to  the 
lateral  surface  of  the  tonsil.  As  the  tonsil  is  separated  from  the  floor  of 
its  recess  by  loose  cellular  tissue  it  can  be  drawn  out  of  this  recess,  still 
farther  from  the  vessels,  for  the  purpose  of  its  removal. 

The  position  of  the  tonsil  corresponds  superficially  to  a  point  a  little 
above  and  in  front  of  the  angle  of  the  jaw,  but,  owing  to  the  intervening 
structures,  enlargement  of  the  tonsil  other  than  malignant  cannot  be 
felt  externally.  What  is  felt  and  mistaken  for  the  tonsil  is  an  enlargement 
of  the  lymph  nodes  here  which  regularly  accompany  affections  of  the 
tonsil.  Enlarged  or  hypertrophied  tonsils  project  in  the  line  of  least 
resistance  toward  the  median  line,  where  they  may  even  meet  and  cause 
difficulty  in  swallowing.  As  the  projecting  mass  of  hypertrophied  tonsils 
also  narrows  the  pharyngeal  passageway  between  the  nose  and  the  larynx, 
the  subject  of  such  hypertrophy  sleeps  with  the  mouth  open,  to  get  more 
air,  and  usually  snores. 

In  the  inflammation  known  as  follicular  tonsillitis  the  openings  of  the 
twelve  or  fifteen  crypts  on  the  free  internal  surface  of  the  tonsil  are 
filled  with  a  yellowish-white  deposit  composed  of  desquamated  epithe- 
lium, leukocytes,  bacteria,  etc.  The  decomposition  of  retained  epithelial 
structures  and  food  debris  within  the  crypts  of  an  enlarged  tonsil  may 
give  rise  to  foul  breath  and  to  the  repeated  attacks  of  inflammation 
to  which  such  tonsils  are  liable.  The  attachment  of  the  tonsil  to  the 
muscles  of  the  pharynx  renders  deglutition  painful  in  acute  inflammations 
of  the  tonsil,  because  of  the  movements  conveyed  to  the  latter  by  the 
movements  of  the  pharynx.  Thus  the  superior  constrictor  moves  it 
inward  and  the  stylopharyngeus  outward.  The  action  of  the  latter  in 
drawing  the  tonsil  outward,  combined  with  a  prominent  anterior  faucial 
pillar,  may  make  it  difficult  to  reach  the  tonsil  with  the  tonsillotomy.  The 
latter  should  be  introduced  backward  and  slightly  downward,  for  this  is 
the  direction  of  the  long  axis  oi  the  tonsil,  which  normally  measures  about 
2.5cm. '  1  in  j.    Its  postero-inferior  end  is  sometimes  hard  to  inspect. 

Although  the  blood  supply  is  from  multiple  sources,  the  uninflamed 
tonsil  is  Dot  very  vascular,  so  that  it  often  bleeds  but  little  on  removal, 
but  if  removed  when  inflamed  it  may  give  rise  to  troublesome  hemorrhage, 
whieh  may  be  controlled  by  pressure  outward  against  the  jaw.  The 
arterial  supply  comes  from  the  tonsillar  branch  of  the  facial,  the  descend- 
ing palatine  branch  of  the  internal  maxillary,  the  dnrsalis  lingiue  branch 

of  the  lingual  and  branches  of  the  ascending  pharyngeal.  The  lym- 
phatics of  the  tQQSi]   enter  t  Ii  <•  «|e.  p  f  «  |\  if  ;i  1   node-;  I  ""( i  <;i  1 1 1   the  posterior 


126  THE  HEAD  AND  NECK 

belly  of  the  digastric.  These  are  situated. near  the  angle  of  the  jaw, 
and  may  be  readily  felt  when  enlarged.  The  nerves  come  from  Meckel's 
ganglion  and  the  glossopharyngeal  nerve.  The  latter  as  it  winds  around 
the  palatopharyngeus  is  in  such  close  relation  to  the  tonsil  as  to  be  in 
some  danger  of  injury  in  operations  on  or  about  the  tonsil. 

The  tonsil  is  not  infrequently  the  seat  of  malignant  newgrowths, 
sarcoma  and  epithelioma,  on  account  of  which  it  is  removed  with  a  wide 
margin  of  healthy  tissue,  either  through  the  mouth,  after  splitting  the 
cheek  or  dividing  the  jaw,  or  through  the  neck  by  a  lateral  pharyngotomy . 

The  Pharynx. — The  pharynx  extends  from  the  basilar  process  of  the 
occipital  bone  to  the  lower  part  of  the  cricoid  cartilage,  which  is  opposite 
the  sixth  cervical  vertebra  when  the  neck  is  neither  flexed  nor  extended. 
It  is  11  cm.  (4ij  in.)  long,  much  wider  transversely  than  anteroposteriorly, 
widest,  about  4.5  cm.  (If  in.),  between  the  fossae  of  Rosenmiiller,  and 
narrowest,  14  mm.  (f  in.),  at  the  lower  end  where  it  is  continuous  with 
the  esophagus.  Hence  foreign  bodies  which  reach  the  pharynx  are  most 
likely  to  be  arrested  at  the  latter  point,  which  is  a  little  beyond  the  reach 
of  the  finger,  for  it  measures  15  cm.  (6  in.)  from  the  incisor  teeth.  The 
latter  measurement  should  be  remembered  in  passing  esophageal  bougies 
to  determine  the  position  of  a  stricture,  and  it  should  be  added  to  the 
length  of  the  esophagus,  23.5  cm.  (9^in.),  to  determine  the  distance  from 
the  teeth  to  the  stomach. 

The  variety  of  foreign  bodies  reported  as  arrested  in  the  pharynx  is 
very  great.  Perhaps  the  most  common  are  large  masses  of  food  swallowed 
gluttonously,  a  frequent  occurrence  among  the  insane.  When  the  foreign 
body  is  a  large  one  it  may  block  the  laryngeal  opening  and  thereby  cause 
suffocation.  As  corrosive  fluids  pass  the  narrowest  point  more  slowly 
than  the  wider  parts,  the  corrosive  action  is  more  intense  and  the  resulting 
cicatricial  contraction  more  marked  at  the  lower  end  of  the  pharynx  than 
they  are  above. 

The  pharynx  is  complete  behind  and  at  the  sides,  where  its  musculo- 
membranous  walls  separate  it  from  the  surrounding  parts.  It  is  incom- 
plete in  front,  where  it  presents  the  openings  of  the  posterior  nares  above, 
the  faucial  opening  into  the  mouth  below,  and  still  lower  the  upper  orifice 
of  the  larynx.  The  front  of  the  pharynx  is  held  open  by  its  attachment  to 
the  following  fixed  points,  the  internal  pterygoid  plate,  mandible,  hyoid 
bone,  and  thyroid  and  cricoid  cartilages. 

Relations  of  the  Pharynx. — The  posterior  wall  of  the  pharynx  is  in 
front  of  the  bodies  of  the  upper  five  cervical  vertebra.  The  anterior 
arch  of  the  atlas  is  on  a  level  with  the  palate,  and  behind  the  mouth 
one  can  palpate  the  anterior  surface  of  the  bodies  of  the  second  and 
third  cervical  vertebrae,  and  so  determine  the  existence  of  a  fracture, 
dislocation,  or  disease  of  these  vertebrae.  Owing  to  their  distance  from 
the  incisor  teeth  it  is  difficult  to  satisfactorily  palpate  the  fourth  and  fifth 
cervical  vertebrae.  Necrosed  portions  of  the  upper  cervical  vertebrae 
have  been  discharged  through  the  mouth. 

In  caries  of  the  upper  cervical  vertebrae,  which  is  most  common  in 
children,  a  retropharyngeal  abscess  may  form  in  the  loose  tissue  sepa- 


THE  FACE 


127 


rating  the  posterior  pharyngeal  wall  from  the  prevertebral  fascia.     One 

or  two  lymph  nudes  on  either  side  situated  in  this  loose  tissue  opposite 
the  lateral  masses  of  the  atlas  receive  lymph  vessels  from  the  nasal 
fossa?,  the  nasopharynx,  the  Eustachian  tubes,  etc.,  and  may  also  be  the 
starting  point  of  such  an  abscess.  These  abscesses  may  push  forward 
the  posterior  pharyngeal  wall  so  as  to  depress  the  soft  palate,  or,  if  they 
extend  farther  downward,  they  may  cause  dyspnea  by  obstructing  the 
opening  into  the  larynx.  Though  they  may  open  or  be  opened  through 
the  mouth,  it  is  preferable  to  open  them  by  an  incision  along  the  sterno- 


Fi<;.  47 


eUSTACHIA 
TUBE 


THYRO-HYOID 
BURSA 


THYRO-HYOID 

MEMBRANE 

THYRO-HYOID 

MUSCLE 
FAT    IN     FRONT 
OF    EPIGLOTTIS 

THYROID    CAR- 
TILAGE 


SPHENOIDAL    SINUS 


,\'-> «\\     PHARYNGEAL   TONSIL 
^i*i-PHARYNGEAL    RECESS 


ANTERIOR    ARCH 
OF    ATLAS 


ARYTENO-EPI- 
GLOTTIC    FOLD 


ARYTENOID 
MUSCLE 


Sagittal  lection  of  the  pharynx,  etc.     (Zuckerkandl.) 


mastoid,  either  in  front  >or  behind,  after  passing  behind  the  great  vessels 

and  the  parotid  gland.    This  is  especially  true  in  tuberculous  abscesses,  to 

avoid  mixed  infection.    If  they  discharge  spontaneously  into  the  pharynx 

during  sleep,  the  pus  may  be  inspired  and  cause  suffocation  or  sel  up 

septic  pneumonia.     Abscess  in   this  loose  retropharyngeal  tissue  may 

id  along  the  esophagus  into  the  posterior  mediastinum,  even  to  the 

diaphragm.     This  loose  tissue  serves  the  purpose  of  a  serous  cavity  and 

allow    di<-  tree  movement*  <>\'  die  pharynx. 

The  lateral  walls  of  the  pharynx  are  in  close  relation  with  the  internal 
rami nl  arteries  and  their  accompanying  aen  es  (ninth,  tenth,  and  eleventh 


128  THE  HEAD  AND  NECK 

and  sympathetic  nerves)  (see  Fig.  46),  so  that  the  pulsations  of  the  artery 
may  be  felt  through  the  pharyngeal  wall  and  the  artery  may  be  wounded 
by  foreign  bodies  thrust  through  the  wall.  The  internal  jugular  vein  is 
less  exposed  to  injury  from  such  causes,  as  it  is  more  laterally  placed. 
The  styloid  process  and  its  muscles,  the  inner  end  of  the  parotid  gland,  and 
the  upper  end  of  the  thyroid  gland  are  also  in  relation  with  the  lateral 
walls  of  the  pharynx.  If  epithelioma  involves  a  part  of  the  pharynx,  as 
occasionally  happens,  with  or  without  invasion  of  the  tonsil,  it  may  be 
reached  through  an  incision  on  the  side  of  the  neck.  In  such  cases  the 
external  carotid  is  tied,  and,  in  order  to  reach  the  upper  end  of  the 
pharynx,  a  division  or  temporary  resection  of  the  jaw  may  be  made. 
The  lower  end  of  the  pharynx  may  also  be  reached  by  subhyoid  pharyn- 
gotomy  through  the  thyrohyoid  membrane,  an  operation  which  also 
exposes  the  portion  of  the  larynx  above  the  glottis. 

The  Nasopharynx. — The  nasopharynx,  or  the  upper  part  of  the 
pharynx  which  is  above  the  level  of  the  palate  and  behind  the  posterior 
nares,  is  entirely  respiratory  in  function.  Accordingly  its  epithelium  is 
ciliated,  and  it  is  shut  off  from  the  lower  or  buccal  portion,  during  the  act 
of  swallowing,  by  the  elevation  of  the  soft  palate.  The  superior  constrictor 
does  not  reach  to  its  upper  end  at  the  sides,  as  the  constriction  of  this 
part  serves  no  purpose.  In  Politzer's  method  of  inflating  the  middle  ear 
the  nasopharynx  is  shut  off  from  the  parts  below  by  the  act  of  swallowing, 
in  which  the  palate  is  raised,  so  that  the  air  forced  into  the  nose  finds  no 
exit  except  through  the  Eustachian  tube. 

The  nasopharynx  is  very  rich  in  lymphoid  or  adenoid  tissue,  and  a  mass 
extending  around  its  posterior  wall  between  the  orifices  of  the  Eustachian 
tubes  is  known  as  the  pharyngeal  or  Luschka's  tonsil,  which  is  often  hyper- 
trophied.  Such  hypertrophy  is  frequent,  and  may  reduce  Rosenmuller's 
fossa  to  a  narrow  fissure.  Reaching  from  this  point  forward,  the  mucosa 
of  the  roof  and  upper  part  of  the  pharynx  is  rich  in  similar  tissue  which, 
when  hypertrophied,  gives  rise  to  nasopharyngeal  adenoids.  The  latter 
obstruct  the  posterior  nares ;  compress  and  obstruct  the  openings  of  the 
Eustachian  tubes;  are  a  common  cause  of  deafness  and  otitis  media; 
cause  mouth  breathing,  snoring,  frequent  colds,  running  of  the  nose,  lack 
of  development  of  the  nose  and  the  body  of  the  maxillae,  resulting  in  a  high 
arch  of  the  palate;  affect  the  voice;  and  are  often  associated  with  mental 
apathy  and  dulness.  After  puberty  they  tend  to  diminish  and  the  naso- 
pharynx also  becomes  more  capacious;  but  before  this  time  they  should 
be  removed,  if  well-marked,  to  avoid  the  many  evil  consequences. 

The  roof  and  posterior  wall  of  the  nasopharynx  is  formed  by  the  obliquely 
sloped  under  surface  of  the  body  of  the  sphenoid  and  of  the  basilar  process 
of  the  occipital  bone  and  the  thick  layer  of  ligaments  and  fibrous  tissue 
which  fills  in  the  angle  between  the  latter  and  the  vertebrae.  From  this 
fibrous  tissue,  or  the  periosteum,  spring  the  nasopharyngeal  polypi,  which 
may  be  pedunculated  or  sessile,  benign  or  sarcomatous,  and  which  occur 
most  often  in  male  children.  Even  when  benign  they  may  by  their 
growth  fill  up  the  nasopharynx,  depress  the  soft  palate,  become  pro- 
longed into  the  nasal  fossa?,  the  maxillary  sinuses,  and  even  through  the 


THE  NECK  129 

sphenopalatine  foramen,  and  they  may  possibly  erode  the  base  of  the 
skull.  Their  removal  if  pedunculated  may  be  secured  by  a  wire  snare 
or  galvanocautery  loop  introduced  through  the  nose,  through  a  tempo- 
rary resection  of  the  maxilla,  a  division  of  the  palate,  and  in  many  other 
ways.  After  about  twenty  years  of  age  they  grow  much  less  rapidly  or 
not  at  all,  and  are  even  said  to  atrophy,  hence  the  removal  of  a  small 
one  at  this  time  may  be  unnecessary  so  far  as  its  mechanical  obstruction 
is  concerned. 

The  lower  port  of  the  pharynx  is  funnel-shaped,  narrowing  to  its  nar- 
rowest point  at  its  lower  end.  All  below  the  nasopharynx  is  lined  by 
stratified  epithelium.  Both  the  stylo-  and  palatopharyngei  elevate  the 
pharynx,  the  former  also  widens  it,  and  the  latter  narrows  very  strongly 
the  isthmus  of  the  fauces  and  helps  to  shut  off  the  mouth  from  the  pharynx 
in  the  second  act  of  deglutition. 

The  lymphatics  of  the  pharynx  pass  to  the  upper  deep  cervical  nodes, 
whose  enlargement  may  depend  upon  an  inflammation  or  some  other 
affection  of  the  pharynx.  The  lymphatics  of  the  upper  part  of  the 
pharynx  first  pass  through  the  postpharyngeal  node. 


THE  NECK. 

The  neck  or  the  passageway  between  the  head  and  the  thorax  is 
subject  to  wide  variations  as  to  its  length,  size,  and  shape.  The  abundance 
or  lack  of  adipose  tissue  is  largely  responsible  for  the  increase  or  decrease 
of  size  and  for  the  rounded  or  angular  shape.  In  extension  of  the  neck 
its  anterior  part  is  lengthened  and  in  flexion  is  shortened,  so  that 
the  distance  of  its  movable  parts  from  the  sternum  or  the  lower  jaw  varies, 
as  i Iocs  also  the  relation  of  these  parts  to  the  vertebrae.  Hence  in  giving 
the  relative  position  of  its  landmarks,  the  neck  is  supposed  to  be  in  the 
position  midway  between  flexion  and  extension,  i.  e.,  the  natural  upright 
position,  unless  otherwise  stated. 

Landmarks  and  Surface  Markings.— Anterior  Median  Region. — In  the 
angle  between  the  chin  and  the  neck  the  hyoid  bone  and  its  great  cornua 
can  be  made  out.  The  body  of  the  bone  is  on  a  level  with  the  fourth 
cervical  vertebra  and  nearly  on  a  level  with  the  angles  of  the  jaw.  The 
upper  borders  of  the  cornua  are  guides  to  the  lingual  arteries  which  run 
jusl  above  them.  Below  the  hyoid  bone  is  the  thyrohyoid  membrane, 
which  corresponds  posteriorly  with  the  epiglottis  and  the  upper  aperture 
of  the  larynx.  This  membrane  is  limited  inferiorly,  one  finger's  breadth 
below  the  hyoid,  by  the  thyroid  cartilage,  whose  upper  border  corresponds 
to  the  bifurcation  of  'lie  common  carotid.  The  parts  of  the  thyroid  car- 
tilage and  the  cricothyroid  space,  between  it  and  the  cricoid  cartilage  below, 
can  he  readily  made  out.  The  projection  of  the  thyroid  angle  (poniiini 
Adami )  is  much  more  prominent  in  males  after  puberty,  but  the  cricoid  is 

always  to  be  madeoui  about  3  cm.  CI  \  in.)  below  its  upper  end.  It  corre- 
tvonds  to  the  upper  end  of  the  sixth  cervical  vertebra,  to  the  junction  of  the 
pharynx  and  esophagus  and  of  the  larynx  and  trachea,  and  to  the  crossing 


130  THE  HEAD  AND  NECK 

of  the  common  carotid  by  the  omohyoid  muscle.  Below  the  cricoid  the 
trachea  may  be  felt,  but  its  individual  rings  cannot  be  distinguished.  As 
it  descends  it  becomes  less  easily  felt,  for  it  is  covered  more  deeply  by 
the  lower  thicker  part  of  the  neck,  so  that  at  the  episternal  notch,  on  a 
level  with  the  disk  between  the  second  and  third  thoracic  vertebrae,  it 
lies  nearly  3.5  cm.  (1-J  in.)  from  the  surface. 

The  thyroid  gland  cannot  be  distinctly  felt  unless  enlarged.  On  deep 
pressure  opposite  the  cricoid  cartilage,  over  the  line  of  the  carotid  artery, 
the  prominent  anterior  tubercle  of  the  sixth  cervical  vertebra  can  be 
felt,  and  the  artery  can  be  compressed  against  it,  as  advised  by 
Chassaignac.  Hence  it  is  called  the  carotid  tubercle  or  Chassaignac's 
tubercle.  As  the  omohyoid  crosses  the  carotid  at  this  point,  the  latter  is 
more  superficial  and  more  easily  compressed  just  above  it.  The  vertebral 
artery  may  be  controlled  by  pressure  below  it. 

In  the  median  line  at  the  back  of  the  neck  there  is  a  slight  depression 
between  the  prominences  which  are  due  to  the  trapezius  and  complexus 
muscles  on  either  side.  At  the  upper  end  of  this  depression  is  the  occip- 
ital protuberance,  about  5  cm.  (2  in.)  below  this  the  spine  of  the  axis  can 
be  felt  on  deep  pressure,  and  below  this  the  spines  of  the  third,  fourth, 
and  fifth  vertebrae  can  be  felt  as  a  bony  ridge,  but  not  commonly  as  indi- 
vidual spines.  The  spine  of  the  vertebra  prominens  (seventh  cervical)  can 
be  very  plainly  felt,  and  represents  the  lower  limit  of  the  neck.  The  spine 
of  the  first  dorsal  is  still  more  prominent.  In  most  cases  the  sixth  spine 
can  be  distinctly  felt  and  sometimes  it  may  be  even  mistaken  for  the 
seventh  spine.     The  sixth  cervical  is  commonly  the  last  bifid  spine. 

At  the  side  of  the  neck  the  transverse  process  of  the  atlas  may  be  felt 
just  below  and  in  front  of  the  tip  of  the  mastoid  process,  and  in  the  upper 
part  of  the  supraclavicular  fossa  the  transverse  process  of  the  seventh 
cervical  vertebra  can  be  felt  on  deep  pressure.  The  angle  between  the 
submental  region  and  the  neck  corresponds  about  to  the  hyoid  bone  and 
is  continued  as  a  groove  and  a  crease  in  the  skin  backward  and  upward 
beneath  the  angle  of  the  jaw  to  the  subauricular  depression  in  front  of 
the  mastoid,  behind  the  jaw  and  below  the  ear.  In  very  fat  subjects  it 
may  not  be  present.  The  groove  corresponds  to  the  line  of  Kocher's 
incision  for  the  upper  cervical  triangle. 

The  sternomastoid  muscle  is  altogether  the  most  important  landmark 
of  the  neck.  It  is  prominent  in  thin  subjects  and  when  thrown  into 
action.  Its  anterior  border  is  the  thicker  and  better  marked,  and  along  it 
runs  a  communicating  branch  from  the  facial  to  the  anterior  jugular 
vein  in  the  lower  part  of  the  neck.  Extending  from  the  tip  of  the  mastoid 
to  a  point  just  internal  to  the  sternoclavicular  joint,  this  border  overlies 
the  common  carotid,  the  pulsation  of  which  can  be  felt  on  slight  pressure, 
and  is  the  guide  for  many  incisions.  The  sheath  of  the  muscle,  which  is 
derived  from  the  superficial  layer  of  the  deep  cervical  fascia,  is  thicker 
near  the  middle  of  the  muscle  than  below  or  above.  The  triangular 
interval  between  the  sternal  and  clavicular  heads  of  the  muscle  is  very 
evident  in  thin  subjects  as  a  slight  depression.  Beneath  the  lower 
end  of  this  interval,  i.  e.,  just  above  the  sternoclavicular  joint,  lies  the 


THE  NECK  131 

common  carotid  on  the  left  and  the  bifurcation  of  the  innominate  artery 
on  the  right  side,  and  on  both  sides  the  margin  of  the  pleura  and  lungs 
at  a  deeper  level. 

The  action  of  the  stemomastoid  of  one  side  is  to  flex  the  head  forward 
and  laterally,  to  the  side  of  the  muscle,  and  rotate  it  to  the  opposite  side. 
The  fibers  of  the  sternal  fasciculus  cross  superficial  to  those  of  the 
clavicular  portion  so  as  to  be  inserted  behind  them  above.  The  cla- 
vicular portion  produces  the  lateral  flexion,  the  sternal  'portion  the  rota- 
tion. This  difference  of  action  is  important,  and  is  illustrated  in  torticollis 
or  wryneck,  a  condition  often  congenital,  sometimes  acquired,  and  due  to 
a  contracture  or  spasmodic  contraction  of  one  muscle  or  the  paralysis  of 
the  opposite  one. 

The  congenital  cases  are  due  most  often  to  an  injury  at  birth,  too  great 
traction  on  the  after-coming  head,  or  the  pressure  of  the  forceps.  A 
hematoma  forms  within  the  sheath  of  the  ruptured  or  injured  muscle 
and  the  injured  part  is  replaced  by  fibrous  tissue,  or  the  pressure  of  the 
extravasation  causes  an  ischemic  degeneration  and  contracture.  Accord- 
ing to  some  the  latter  may  occur  from  pressure  in  utero.  The  deformity 
may  not  be  noticed  for  some  time  after  birth  and  increases  with  the 
cicatricial  contraction  of  the  injured  muscle  and  cervical  fascia  and  with 
the  diminished  growth  of  the  muscle.  In  this  form  of  wryneck  the  treat- 
ment is  division  of  the  muscle.  This  was  formerly  practised  subcutane- 
otuly  2  cm.  ($  in.)  above  its  lower  end  in  adults,  1  cm.  above  in  children, 
so  as  to  avoid  the  anterior  jugular  vein  which  passes  beneath  the  lower 
end  of  the  muscle  to  join  the  external  jugular,  which  lies  along  its  pos- 
terior border.  The  latter  vein  is  generally  out  of  danger,  as  only  the 
sternal  portion  of  the  muscle  is  usually  divided,  for  it  is  the  rotation  due 
to  this  portion  which  is  particularly  characteristic  of  torticollis.  The 
great  vessels  are  not  in  danger,  as  they  are  here  overlapped  by  the  sterno- 
hyoid and  sternothyroid  muscles.  The  open  division  is  far  preferable,  as 
everything  can  be  divided  that  prevents  the  correction  of  the  deformity, 
including  the  contracted  sheath  and  the  cervical  fascia.  It  should  be 
done  before  secondary  changes  in  the  vertebrae  and  soft  parts  have  taken 
place. 

Spastic  wryneck  may  be  due  to  a  reflex  irritation.  The  spinal 
accessory  hit  re,  together  with  a  few  fibers  of  the  second  and  third  cer- 
vical /"'/wr*,  supplies  the  muscle.  In  such  forms  of  wryneck  the  spinal 
accessory  is  often  excised  and  may  be  exposed  where  it  reaches  the  anterior 
border  of  the  muscle,  2.5  to  .'!.",  cm.  (1  to  \\  in.)  below  the  tip  of  the 
mastoid.  Tins  nerve  Ira  verses  tin;  muscle  about  the  junction  of  its 
upper  ami  middle  thirds,  emerges  at,  the  posterior  border  a  little  above 
its  middle,  cro  sea  the  posterior  triangle  obliquely  and  passes  under  the 
trapezius  on  a  level  with  the  seventh  cervical  spine.  It  supplies  the 
hitter  in  conjunction  with  the  third  and  fourth  cervical  nerves.  In  some 
severe  rases  of  spastic  wryneck  the  trapezius  and  other  muscles  at  the 
back  of  the  neck  are  involved,  andjbesides  the  spinal  accessory  (he  pos- 
terior- primary  divisions  of  the  upper  three  or  four  cervical  nerves  may 
require  resection,    The  spinal  accessory  may  be  divided  in  operations  on 


132  THE  HEAD  AND  NECK 

the  neck,  especially  in  operations  for  enlarged  glands.  The  effect  of  this 
is  variable.  In  some  cases  the  stern omastbid  muscle  is  paralyzed  and 
atrophied,  in  others  it  is  not.  This  difference  is  explained  by  the  fact 
that  the  nerve  supply  furnished  by  the  cervical  nerves  is  sometimes  very 
slight,  and  that  it  sometimes  reaches  the  muscle  throughout  the  spinal 
accessory  in  other  cases  separately.  The  trapezius  is  less  often  affected. 
The  spinal  accessory  is  sometimes  used  for  anastomosis  with  the  facial 
nerve  in  persistent  paralysis  of  the  latter. 

Besides  forming  a  guide  for  the  incision  in  many  operations,  the 
sternomastoid  divides  the  anterolateral  region  of  the  neck,  in  front  of  the 
trapezius  muscle,  into  two  triangles.  These  primary  surgical  triangles  are 
subdivided  into  several  smaller  surgical  triangles  by  muscles  which  are 
also  of  service  as  landmarks  in  operations  on  the  neck.  These  triangles 
bounded  by  and  containing  landmarks  are  of  practical  use,  for  their 
contents  can  be  located  with  reference  to  these  boundaries  and  landmarks. 

The  posterior  triangle  (Fig.  48)  is  subdivided  by  the  posterior  belly  of 
the  omohyoid  into  an  inferior  or  subclavian  and  a  superior  or  occipital 
triangle.  The  occipital  triangle,  bounded  by  the  sternomastoid  in  front, 
the  trapezius  behind,  and  the  omohyoid  below,  contains  comparatively 
little  of  practical  importance.  The  superficial  cervical  nerves  appear  at 
the  posterior  border  of  the  sternomastoid.  The  small  occipital,  great 
auricular,  and  transverse  cervical  nerves  emerge  just  above  the  centre 
of  the  muscle,  the  first  running  up  to  the  scalp  near  the  posterior  border 
of  the  muscle,  the  second  across  the  muscle  to  the  back  of  the  ear,  the 
third  straight  forward  across  the  muscle.  Lines  drawn  from  the  middle 
of  the  posterior  border  of  the  muscle  to  the  sternum,  the  middle  of  the 
clavicle,  and  the  acromion  represent  the  course  of  the  suprasternal, 
supraclavicular,  and  supra-acromial  nerves.  The  spinal  accessory  nerve 
crosses  this  triangle  as  described  above. 

The  subclavian  triangle  (Fig.  48)  about  corresponds  to  the  wide  depres- 
sion above  the  clavicle,  the  supraclavicular  fossa,  which  is  well-marked 
except  in  stout  subjects  and  infants.  In  some  fractures  of  the  clavicle 
this  fossa  may  be  obliterated  or  even  replaced  by  a  prominence.  This 
triangle  is  bounded  below  by  the  clavicle,  above  by  the  posterior  belly  of 
the  omohyoid,  and  in  front  by  the  posterior  border  of  the  sternomastoid. 
The  posterior  belly  of  the  omohyoid  can  be  made  out  in  thin  necks  and 
especially  when  in  action.  It  runs  along  a  little  above  the  clavicle, 
inclining  somewhat  upward  as  it  passes  forward  to  pass  beneath  the 
sternomastoid,  about  2.5  cm.  (1  in.)  above  the  clavicle.  The  posterior 
border  of  the  latter  can  be  made  out  when  in  action.  The  attachment  of 
its  clavicular  portion  varies  in  width,  and  in  some  cases,  especially  in 
muscular  subjects,  it  encroaches  on  the  subclavian  triangle  so  as  to  require 
division  in  operations  in  this  region. 

At  a  deeper  level  the  posterior  border  of  the  scalenus  anterior  muscle 
roughly  corresponds  to  that  of  the  sternomastoid,  though  it  has  a  some- 
what different  direction.  Hence  we  may  say  that  there  are  two  triangles 
of  which  the  deeper  is  bounded  in  front  by  the  scalenus  anterior.  It  is 
more  readily  felt  and  a  better  landmark  than  the  scalene  tubercle.    The 


PLATE  VI 


FIG.  48 


SPINAL    ACCES- 
SORY   NERVE 


POSTERIOR    SCAP 
ARTERY 


SERRATUS 
MAGNUS 
MUSCLE 


SCALENUS 
MEDIUS 
MUSCLE 

PHRENIC 
NERVE 


BRACHIAL 
PLEXUS 


SUPRASCAP. 
ARTERY 


LONG    THORA- 
CIC   NERVE 


The  Occipital  and  Subclavian  Triangles.  (Zuekerkandl.) 

The  head  is  turned   away  to   the   lefl    and   the  clavicle  is  strongly  depressed.     The 

posterior   scapular  artery  i-   unusually  deep  and    1 1 .•  i ~   separated  unusually  early  from    the 
superficial  cervical  artery. 


THE  NECK  133 

phrenic  nerve  lies  in  front  of  this  muscle  and  crosses  it  obliquely,  being 
directed  toward  the  lower  end  of  its  inner  border,  where  it  passes  behind 
the  subclavian  vein.  It  has  been  known  to  pass  over  the  third  portion 
of  the  subclavian  (Agnew).  This  nerve  commences  at  about  the  level  of 
the  hyoid  bone,  and  is  formed  by  branches  from  the  third  and  fourth 
cervical.  It  lies  deeply  and  descends  underneath  the  sternomastoid, 
being  about  midway  between  its  two  borders  at  the  level  of  the  cricoid 
cartilage. 

Crossing  the  outer  surface  of  the  sternomastoid  and  the  subclavian  tri- 
angle in  a  line  from  the  angle  of  the  jaw  to  the  centre  of  the  clavicle  is 
the  external  jugular  vein.  It  crosses  the  sternomastoid  obliquely  to  reach 
its  posterior  border,  the  lower  third  of  which  it  follows.  The  lower 
dilated  end  or  ''sinus"  of  the  vein,  between  a  point  3.5  cm.  (1^  in.)  above 
the  clavicle,  where  it  pierces  and  is  adherent  to  the  deep  cervical  fascia, 
and  its  entrance  into  the  subclavian  vein  in  front  of  the  scalenus  anterior, 
receives  the  transverse  cervical  and  suprascapular  veins.  These  veins 
sometimes  present  a  plexiform  arrangement  in  the  subclavian  triangle, 
and  may  render  more  difficult  the  operations  in  this  triangle.  Owing 
to  its  adherence  to  the  deep  cervical  fascia  the  "sinus"  of  this  vein 
remains  patent  and  is  liable  to  admit  air  when  it  is  opened. 

At  the  floor  of  the  triangle  the  subclavian  artery  describes  a  curve  from 
the  sternoclavicular  joint  to  the  centre  of  the  clavicle,  the  highest  point 
of  the  curve  rising  12  to  25  mm.  (^  to  1  in.)  above  that  bone.  On  the 
left  side  the  artery  lies  more  deeply  and  does  not  rise  so  high  in  the  neck 
as  on  the  right  side.  At  the  outer  border  of  the  sternomastoid  and  just 
above  the  clavicle  the  pulsation  of  the  artery  may  be  felt,  and  here  it  may 
be  compressed  against  the  first  rib  by  pressure  downward  and  backward 
when  the  arm  is  drawn  downward.  Normally  the  artery  does  not  rest 
directly  upon  the  rib,  but  is  slung,  as  it  were,  6  mm.  (£  in.)  or  more 
above  it,  between  the  scaleni  anterior  and  medius. 

The  artery  may  be  ligated  in  its  third  portion,  which  lies  in  this  triangle 
external  to  the  scalenus  anterior,  by  an  incision  about  10  cm.  (4  in.)  long 
a  finger's  breadth  above  the  clavicle.  The  layers  divided  in  reaching  the 
artery  are  the  following:  (1)  skin;  (2)  scanty  subcutaneous  connective 
tissue;  (3)  platysma;  (4)  second  connective-tissue  layer  with  fat;  (5) 
superficial  layer  of  deep  cervical  fascia  from  the  sheaths  of  the  sterno- 
mastoid and  trapezius;  (6)  third  layer  of  loose  connective  tissue;  (7) 
middle  layer  of  deep  eervieal  fascia,  forming  the  sheath  of  the  omohyoid 
and  connected  with  the  subclavian  vein;  (8)  fourth  layer  of  connective 
tissue  in  which  lie  the  lymph  nodes,  the  end  of  the  external  jugular  vein, 
the  subclavian  artery  and  vein  and  their  branches,  and  the  brachial 
plexus,  etc.  The  external  jugular  vein  (see  above)  should  be  cut  between 
two  ligatures,  as  should  also  the  suprascapular  vein.  The  suprascapular 
and  transverse  cervical  branches  of  the  subclavian  artery  run  outward 

parallel  with  the  elavicle,  the  former  behind,  the  latter  just  above  it 
where  it-,  pulsation  may  usually  be  felt.     The  former  is  usually  below  and 

the  latter  above  die  line  of  incision.    The  supraclavicular  nerves  deacend 

in  front  of  this  triangle.       The  subclavian  vein //V.v  below,  interna  I  to  and 


134  THE  HEAD  AND  NECK 

in  front  of  the  artery  and  under  cover  of  the  clavicle.  ^To  avoid  injury  to 
the  vein  the  aneurysm  needle  should  be  passed  from  below  and  in  front, 
to  avoid  including  a  nerve  cord  it  should  be  passed  from  above  and 
behind,  and  many  consider  that  the  latter  avoids  the  greater  risk. 

At  the  inner  end  of  this  triangle  the  subclavian  vein  is  separated  from 
the  artery  by  the  scalenus  anterior.  Behind  the  latter  the  artery  lies 
in  contact  with  and  grooves  the  dome  of  the  pleura  and  the  apex  of  the 
lung.  These  structures  should  be  carefully  avoided  in  passing  the 
ligature.  Strict  asepsis  should  be  observed  to  avoid  inflammation  of 
the  pleura  and  empyema.  The  pleura  has  also  been  opened  in  removing 
deeply  seated  tumors  at  the  base  of  the  neck,  and,  together  with  the  lung, 
has  been  wounded  in  stab  wounds  of  the  neck  and  by  bony  fragments 
in  severe  fractures  of  the  clavicle  or  first  rib.  Abscess  in  this  part  of  the 
neck  has  opened  into  the  pleura,  and  pleurisy  has  also  followed  cellulitis 
here. -js  Hernia  of  the  lung  into  the  neck  during  violent  paroxysms  of 
coughing  has  been  reported.  For  the  position  of  the  lung  and  pleura 
in  the  root  of  the  neck  see  p.  241. 

The  brachial  plexus  can  be  felt  and,  in  very  thin  subjects,  even  seen 
as  a  number  of  firm  cords  in  the  subclavian  triangle.  Its  upper  limit  is 
shown  by  a  line  from  the  side  of  the  cricoid  cartilage  to  a  point  a  little 
external  to  the  middle  of  the  clavicle.  It  lies  just  above  the  subclavian 
artery,  its  lowest  cord  being  partly  behind  the  artery,  and  it  emerges 
like  the  artery  from  between  the  anterior  and  middle  scalene  muscles. 
Hence  it  is  exposed  and  may  serve  as  a  guide  in  ligating  the  subclavian 
artery.  It  has  occasionally  happened  that  a  cord  of  this  plexus  has  been 
included  in  the  ligature  in  place  of  the  artery,  but  the  mistake  is  evident 
from  the  continued  pulsation  in  the  arteries  of  the  arm.  Rupture  of  the 
plexus  occurs  at  birth  (brachial  birth  palsy)  or  subsequently  by  a  forcible 
separation  of  the  head  from  the  shoulder.  This  stretches  and  then  tears 
first  the  upper  roots,  fifth  and  sixth,  and  then,  if  the  force  continues,  the 
lower  ones  as  well.  The  plexus  may  be  reached  by  an  incision  in  this 
triangle  from  the  posterior  border  of  the  sternomastoid,  at  the  junction  of 
its  middle  and  lower  thirds,  to  the  outer  end  of  the  middle  third  of  the 
clavicle. 

The  third  portion  of  the  artery  is  the  seat  of  election  for  ligature,  for 
it  is  more  superficial  and  has  no  branches  and  fewer  vital  relations. 
The  second  part  lies  deeply  behind  the  scalenus  anterior,  on  which  lies 
the  phrenic  nerve.  It  includes  the  highest  point  of  its  curve,  gives  off 
one  branch  (superior  intercostal),  and  is  in  close  relation  with  the  pleura. 
The  first  portion  is  crossed  in  front  by  the  internal  jugular,  vertebral, 
and  the  commencement  of  the  innominate  veins,  and  on  the  right  side 
by  the  pneumogastric  and  a  loop  of  the  sympathetic  nerve.  On  the  left 
side  the  thoracic  duct  arches  over  it.  The  subclavian  vein  is  below  and 
in  front  of  it,  and  it  gives  off  three  large  branches.  Below  and  behind  it 
are  the  pleura  and  lung  and,  on  the  right  side,  the  recurrent  laryngeal 
nerve.  Hence  and  because  of  its  deep  situation  it  is  not  well  suited  for  the 
application  of  a  ligature. 

After  ligature  of  the  second  or  third  portions  of  the  subclavian  the 


THE  NECK  135 

collateral  circulation  is  established  and  carried  on  principally  through 
the  anastomoses,  (1)  of  the  suprascapular  and  posterior  scapular  with 
the  aeromiothoracic,  subscapular  and  dorsalis  scapulae;  (2)  of  the 
superior  intercostal,  aortic  intercostal,  and  internal  mammary  with  the 
long  thoracic  and  the  scapular  arteries;  (3)  of  small  branches  in  the 
axilla. 

Cervical  ribs  when  present  usually  occur  on  both  sides,  sometimes  on 
one  side  only.  As  a  rule,  they  are  articulated  with  the  seventh  cervical 
vertebra  and  its  transverse  process,  but  sometimes  they  are  fused  with  it. 
They  may  be  very  short,  when  they  are  often  mistaken  for  exostoses,  or 
they  may  extend  well  forward  and  be  connected  by  bony,  cartilaginous, 
or  fibrous  union  with  the  first  rib,  its  cartilage,  or  the  sternum.  In  such 
cases  the  subclavian  artery  and  brachial  plexus  pass  over  them,  and  the 
anterior,  and  sometimes  the  middle,  scalene  muscles  are  attached  to  them. 
The  distinct  pulsation  of  the  artery  at  a  high  level  in  such  cases  may 
lead  to  a  diagnosis  of  aneurysm,  and,  in  fact,  the  latter  condition  seems  to 
lie  not  uncommonly  associated  with  cervical  ribs.  The  rib  may  form  a 
distinct  projection  in  thin  persons,  but,  as  a  rule,  it  causes  no  symptoms. 
Sometimes,  however,  the  circulation  in  the  arm  and  the  function  of  the 
branches  of  the  brachial  plexus  is  interfered  with,  apparently  as  the 
result  of  pressure  by  the  ribs  or  of  the  sharp  bend  in  the  artery,  and  hence 
removal  of  the  rib  is  indicated.  i 

The  anterior  cervical  triangle,  in  front  of  the  sternomastoid,  is  sub- 
divided  by  the  digastric  muscle  above  and  the  anterior  belly  of  the  omo- 
hyoid below  into  three  smaller  triangles. 

The  submaxillary  triangle,  or  the  upper  one  of  these  three,  is  bounded 
above  by  the  lower  border  of  the  jaw  and  the  line  of  this  continued  back 
to  the  mastoid  process,  below  by  the  posterior  belly  of  the  digastric 
muscle  and  the  hyoid  bone,  in  front  by  the  median  line.  It  corresponds 
to  the  suprahyoid  region  of  some  authors.  Its  posterior  angle  belongs 
to  and  has  been  described  under  the  parotid  region.  The  posterior  belly 
of  the  digastric  muscle  coincides  with  a  line  from  the  mastoid  process  to 
a  point  just  above  the  junction  of  the  great  comu  and  body  of  the  hyoid 
bone. 

In  the  normal  position  of  the  head  this  region  lies  in  a  nearly  hori- 
zontal  plane  which  accounts  for  the  rarity  of  wounds  here.  When  the 
head  is  extended,  as  it  is  in  operations  on  this  region,  the  latter  is  oblique 
from  above  downward  and  inward.  In  incisions  into  it  we  meet  the 
following  layers  in  succession:  (l)skin;  (2)  platysma,  with  a  connective- 
tissue  layer  on  either  side;  (3)  the  superficial  layer  of  the  deep  cervical 
fascia  forming  a  sheath  for  (4)  the  submaxillary  gland;  (5)  the  muscular 
floor  of  the  triangle,  with  vessels  and  nerves  covered  by  adeeper  layer  of 
fascia  which  is  attached  to  the  hyoid  bone  and  the  mylohyoid  ridge  and 
forms  a  sheath  for  the  digastric  muscle. 

The  platysma  is  quite  closely  connected  with  the  skin,  so  that  the  edges 
of  wounds  cro  ling  the  course  of  the  muscle  an-  Likely  in  be  turned  in. 

Owing  to  the  loose  ti  Lie  beneath  the  muscle  the  skin  and  platysma 
may  be  readily  used  as  a  jlap,  and  the  ilap  so  formed  can  be  freely  dis- 


136  THE  HEAD  AND  NECK 

placed  to  cover  defects  in  the  lower  lip  and  lower  part  of  the  face.  But 
to  cover  defects  in  the  lips  or  cheek  such  flaps  possess  the  disadvantage 
of  not  being  lined  by  mucosa,  so  that  the  final  results  are  disappointing, 
owing  to  the  adhesions  and  contraction  of  the  flap  (see  p.  111).  The 
amount  of  fat  between  the  skin  and  deep  fascia  is  very  variable.  There  is 
often  a  diffuse  deposit  of  fat,  especially  in  the  area  between  the  chin  and 
the  hyoid  bone,  producing  the  so-called  double  or  triple  chin,  thus  con- 
verting the  normal  concavity  of  this  region  into  a  convexity. 

The  superficial  layer  of  the  deep  fascia  splits  to  enclose  the  submaxillary 
gland  in  a  fibrous  sheath  and  is  adherent  to  the  lower  border  of  the  jaw 
and  to  the  hyoid  bone.  It  is  continuous  laterally  with  the  sheath  of  the 
sternomastoid  and  of  the  parotid  gland,  and  in  the  median  line  with  the 
similar  layer  of  the  opposite  side.  It  is  connected  with  the  thick  fascial 
band  from  the  sternomastoid  to  the  angle  of  the  jaw,  which  separates 
the  submaxillary  from  the  parotid  sheath. 

The  submaxillary  gland  differs  from  the  parotid  in  that  its  fibrous 
septa  are  not  closely  connected  with  the  inside  of  its  sheath,  but  it  is 
separated  from  its  sheath  by  loose  connective  tissue,  so  that  it  can  be 
readily  enucleated.  The  submaxillary  gland  is  seldom  inflamed  pri- 
marily, though  of  all  salivary  glands  it  is  most  frequently  the  seat  of 
calculi,  which  by  obstructing  the  duct  may  produce  sudden,  recurring 
attacks  of  acute,  painful  swelling  of  the  gland,  sometimes  accompanied 
by  suppuration. 

Beneath  the  fascia  covering  it  and  along  the  lower  border  of  the  jaw 
from  the  angle  to  the  attachment  of  the  digastric  are  the  three  to  six 
submaxillary  lymph  nodes,  on  the  surface  of  the  gland,  which  receive 
lymphatics  from  the  upper  lip  and  the  lateral  part  of  the  lower  lip, 
the  forepart  of  the  lateral  border  of  the  tongue,  the  gums,  the  nose,  the 
cheek,  and  the  nasal  half  of  both  eyelids.  Hence  these  nodes  may  be 
affected  in  any  inflammatory  affection  or  malignant  newgrowth  of  these 
parts,  and  the  enlarged  or  broken-down  nodes  require  opening  or  removal 
according  to  circumstances.  When  these  lymph  nodes  are  removed  it  is 
often  impossible  to  spare  the  gland,  especially  in  cancerous  conditions, 
and  the  entire  contents  of  the  digastric  triangle  are  then  removed  together. 
In  this  procedure  the  most  important  structure  in  relation  to  the  gland  is 
the  facial  artery,  which  grooves  its  posterosuperior  part,  passing  from  its 
deep  surface  to  the  border  of  the  jaw,  just  in  front  of  the  masseter.  The 
general  direction  of  the  tortuous  facial  artery  is  between  the  latter  point 
and  its  origin,  just  above  and  outside  the  tip  of  the  great  cornu  of  the 
hyoid  bone,  passing  beneath  the  posterior  belly  of  the  digastric  in  its 
course.  The  facial  vein,  usually  separated  from  the  artery  by  the  submax- 
illary gland,  the  posterior  belly  of  the  digastric,  the  stylohyoid  muscle, 
and  the  hypoglossal  nerve,  crosses  superficial  to  the  artery  to  become 
more  posterior  at  the  border  of  the  jaw.  The  submental  branch,  given 
off  from  the  artery  beneath  the  gland,  runs  forward  on  its  deep  surface. 

When  enlarged,  the  posterior  extremity  of  the  gland,  grooved  by  the 
facial  artery  on  its  deep  and  superior  aspect,  may  overlap  the  external 
carotid,  from  which  it  is  separated  by  the  posterior  belly  of  the  digas- 


THE  NECK 


137 


trie,  the  stylohyoid,  and  the  band  from  the  stemomastoid  to  the  angle  of 
the  jaw.  The  gland  lies  partly  hidden  beneath  the  mandible.  Its  acces- 
sory portion  and  duct  [Wharton's)  (Fig.  49)  (see  page  119)  pass  forward 
in  the  floor  of  the  month  on  the  deep  surface  of  the  mylohyoid.  Notice 
the  close  relation  between  this  region  and  the  floor  of  the  mouth;  inflam- 
matory affections  may  spread  from  one  to  the  other  behind  the  mylo- 
hyoid.   In  this  connection  it  should  be  remembered  that  the  commonest 


Fig.  40 


I  lie  talivary  glands.     The  righl  half  of  the  body  of  the  mandible  has  been  removed.     Wharton's 
dad  ij  outlined  by  dotted  lini «  beneath  the  sublingual  gland.     (Gerrish,  after  Testut.) 


of  abscess  in  the  submaxillary  region  is  denial  curies  followed  by 
alveolar  perio  litis  of  the  mandible  (see  page  111').      Inflammation  of 

ibmaxiltary  gland  and  of  the  lymph  nodes  within  its  sheath,  or 
the  al  lilting  therefrom,  is  more  circumscribed  than  the  last- 

mentioned  ab  •  ad  in  opening  submaxillary  abscesses  it  should  be 

remembered  thai  the  facial  vessels  and  their  branches  are  on  the  deep 
surface  of  the  sheath  and  aoi  exposed  to  injury. 

The    tWO    bellies    of    (he    <  I  ig;i.-,t  He    below     .'Hid     (he     j;iw     ;il>oVe    fr.lllie    ;i 


138  THE  HEAD  AND  NECK 

deep  triangle  lodging  the  submaxillary  gland.  The  floor  of  this  triangle  is 
formed  by  the  mylohyoid  and  hyoglossus  muscles  from  before  backward. 
Passing  forward  on  the  latter  muscle  is  the  hypoglossal  nerve,  accompa- 
nied by  the  ranine  vein  (Fig.  50) .  The  lingual  artery  has  much  the  same 
course,  at  a  somewhat  lower  level,  but  it  lies  beneath  the  hyoglossus  and 
upon  the  genioglossus  muscle.  This  artery,  arising  opposite  the  tip  of 
the  great  cornu  of  the  hyoid,  runs  forward  just  above  that  process  and  is 
usually  ligated  in  the  "lingual  triangle."  This  triangle  is  bounded  above 
by  the  hypoglossal  nerve,  in  front  by  the  posterior  border  of  the  mylo- 
hyoid, and  behind  and  below  by  the  posterior  belly  of  the  digastric 
(Fig.  50).  It  is  readily  exposed  on  turning  up  the  submaxillary  gland. 
The  lingual  artery  is  here  reached  by  separating  the  more  or  less  vertical 
fibers  of  the  rather  thin  hyoglossus  muscle,  at  right  angles  to  which  it 
runs.     It  is  accompanied  by  one  or  several  venae  comites. 

To  include  the  dorsalis  lingua?  branch  it  has  been  advised  by  Faraboeuf 
and  others  to  ligate  the  first  portion  of  the  artery,  behind  the  hyoglossus 
muscle,  near  whose  posterior  border  this  branch  is  given  off  and  passes 
upward.  For  this  purpose  the  end  of  the  great  cornu  of  the  hyoid  bone 
is  our  guide,  to  which  the  posterior  fibers  of  this  muscle  are  attached. 
This  part  of  the  artery  is  crossed  by  the  hypoglossal  nerve,  the  facial  and 
lingual  veins,  and  the  digastric  and  stylohyoid  muscles. 

The  sublingual  artery,  usually  given  off  at  the  anterior  border  of  the 
hyoglossus,  may  sometimes  arise  in  the  lingual  triangle,  and  might  then  be 
ligated  in  place  of  the  trunk,  so  that  the  circulation  on  the  same  side  of  the 
tongue  would  not  be  controlled  by  the  ligature.  This  is  probably  not  the 
common  cause  of  hemorrhage  in  operations  on  the  tongue  after  ligation 
of  the  lingual,  but  rather  an  anomaly  wherein  the  lingual  on  one  side  is 
small  and  its  place  is  taken  by  a  large  branch  from  the  opposite  lingual. 

Underneath  the  deep  fascia  beneath  the  chin,  in  the  triangle  between  the 
anterior  bellies  of  the  two  digastrics  and  lying  on  the  mylohyoid  muscles, 
are  usually  two  (1  to  4)  submental  lymph  nodes,  which  receive  vessels 
from  the  middle  of  the  lower  lip  and  gums,  the  floor  of  the  mouth,  the  tip 
of  the  tongue,  and  the  chin,  and  may  be  enlarged  in  affections  of  these 
parts. 

The  submaxillary  gland  and  its  neighboring  lymph  nodes  are  com- 
paratively superficial  and  may  be  easily  reached,  for  removal  or  for  ele- 
vation to  expose  the  lingual  triangle,  by  a  curved  incision  from  just 
below  the  angle  of  the  jaw  to  the  body  of  the  hyoid  bone  and  up  toward 
the  symphysis.  Kocher's  so-called  "normal  incision"  for  the  upper 
lateral  cervical  triangle  passes  from  in  front  of  the  tip  of  the  mastoid  to 
the  middle  of  the  hyoid  bone  and  lies  just  below  the  digastric  and  the 
other  suprahyoid  muscles.  It  avoids  important  nerve  trunks,  which  lie 
above  or  posteriorly,  or  can  be  so  retracted,  for  those  crossing  it  can  be 
retracted  posteriorly,  and  it  gives  access  to  the  bifurcation  and  branches 
of  the  great  vessels.  It  may  be  used  to  expose  almost  any  structure  in 
this  region,  and  leaves  a  narrow  and  unnoticeable  cicatrix. 

The  subhyoid  region  is  divided  into  the  two  carotid  triangles  by  the 
anterior  belly  of  the  omohyoid  muscle.    The  latter  follows  a  line  from 


PLATE  VII 


FIG.  50 


POSTERIO 

BELLY    OF 

DIGASTRIC 

MUSCLE 


RTON'S    DUCT  AND 
P    PART    OF    GLAND 


HYPOGLOS 
NERVE 


GREAT    CORl 
OF   HYOID 


LINGUAL    TRIANGLE, 
WITH   COURSE    OF 
LING.    ARTERY 
COVERED   BY    H  YO- 
GLOSSUS 


Submaxillary  Triangle  and  the    Deep    Relations  of  the 
Submaxillary  Gland.        Testut.) 

Dotted  white  line  indicates  the  position  of   the  gland,  dotted  red  line  the  course 
of  the  lingual  artery  beneath  the  hyoglossus. 


FIG.  51 


EXT.    CAROT 
ARTERY 


OCCIPITAL    ARTERY 

SPINAL    ACCES- 
SORY   NERVE 
HYPOGLOSSAL    NERVE 

INTERNAL  CAROT Illll 

ARTERY 
DESCENDENS  NONI  N.-|| 
LINGUAL    VEIN 

COMMON     FACIAL 
VEIN 


INGUAL  ARTERY 
UP.  LARYNGEAL 
NERVE,  INTER- 
NAL   BRANCH. 


UP.  LARYNGEAL 
NERVE  EXTER- 
NAL   BRANCH 


Structures  of  the  Upper   Part  of  Neck  in    the   Superior  Carotid 
and   Submaxillary  Triangles.     (Zuekerkandl.  i 

The  iternonu  toid  muscle  i-  retracted  lomewhal  backward,  the  diga  trie  i 
dn  ided  and  the  omohyoid  remoA  ed, 


THE  NECK  139 

the  side  of  the  body  of  the  hyoid  at  its  lower  border  to  the  anterior  border 
of  the  sternomastoid  at  the  level  of  the  cricoid  cartilage,  where  it  crosses 
in  front  of  the  common  carotid  and  behind  the  sternomastoid. 

The  superior  carotid  triangle  is  bounded  behind  by  the  sternomastoid, 
above  by  the  posterior  belly  of  the  digastric,  and  below  and  in  front  by 
the  anterior  belly  of  the  omohyoid.  Its  floor  is  formed  by  the  thyrohyoid, 
hvoglossus,  and  inferior  and  middle  constrictor  muscles  of  the  pharynx. 
It  contains,  beneath  the  skin,  the  platysma,  and  the  superficial  and  middle 
layers  of  the  deep  cervical  fascia,  the  lower  portion  of  the  external  carotid 
with  the  commencement  of  its  lower  five  branches,  and,  beneath  the  ante- 
rior margin  of  the  sternomastoid,  the  upper  end  of  the  common  carotid 
and  the  lower  part  of  the  internal  carotid. 

The  superior  thyroid  artery  arises  a  little  below  the  great  cornu  of  the 
hyoid  and  runs  downward  and  forward  to  the  back  part  of  the  thyroid 
cartilage  and  the  upper  and  outer  part  of  the  thyroid  body.  It  is  super- 
ficial only  at  its  commencement.  Beneath  it  is  the  superior  laryngeal 
nerve,  whose  internal  branch,  with  the  superior  laryngeal  branch  of  this 
artery,  pierces  the  thyrohyoid  membrane.  Its  sternomastoid  branch, 
arising  about  12  mm.  (^  in.)  from  its  origin,  and  crossing  the  upper  end 
of  the  common  carotid  to  reach  the  sternomastoid  muscle,  is  divided  in 
incisions  along  the  anterior  border  of  the  latter. 

The  occipital  artery,  arising  at  the  same  level  as  the  facial  (p.  136),  but 
from  the  posterior  aspect  of  the  artery,  passes  upward  and  backward 
to  the  interval  between  the  mastoid  process  and  the  transverse  process 
of  the  atlas.  It  finally  enters  the  scalp  with  the  great  occipital  nerve 
midway  between  the  mastoid  process  and  the  external  occipital  protu- 
berance, and  follows  thence  the  line  of  the  lambdoid  suture.  The  facial 
and  lingual  branches  have  already  been  referred  to. 

The  inferior  carotid  triangle  is  bounded  above  by  the  anterior  belly  of 
the  omohyoid,  behind  by  the  sternomastoid,  and  in  front  or  mesially  by 
the  median  line.  The  carotid  triangles  are  so  called  from  their  containing 
the  carotid  vessels,  which,  strictly  speaking,  are  in  great  part  behind  these 
triangles  under  cover  of  the  anterior  border  of  the  sternomastoid. 

The  Great  Vessels. — The  line  of  the  carotid  is  from  the  sternoclavicular 
joint  to  a  point  midway  between  the  angle  of  the  jaw  and  the  mastoid 
process.  The  common  carotid  extends  up  to  the  upper  border  of  the 
thyroid  cartilage,  where  it  bifurcates  into  the  external  and  internal  caro- 
t i< Is.  At  its  point  of  bifurcation  it  presents  a  slight  dilatation,  which  is  the 
most  common  situation  for  aneurysms,  for  there  appears  to  be  increased 
resistance  to  the  blood  current  here.  Such  an  aneurysm  may  demand  the 
proximal  ligature  of  the  carotid.  The  carotid,  having  no  collateral 
branches,  is  also  the  vessel  best  adapted  to  the  distal  ligature  (Basador's 
method),  for  by  occluding  the  artery  it,  prevents  the  blood  passing 
through  the  aneurysm.    It  is  mosi  often  practised  for  aneurysms  in  its 

lower  part,  where  they  arc  not  uncommon.  Ward rop'a  operation,  or  the 
distal  ligature  of  large  brandies  for  aneurysm  of  B  main  trunk,  lias  been 
tried  here,  and  is  now  limited  to  the  ligature  of  the  carotid,  and  the  third 

portion  of  the  mbclavian  for  aneurysms  of  the  innominate,  or  occasionally 


140  THE  HEAD  AND  NECK 

of  the  aorta.  But  as  there  are  large  branches  given  off  from  the  first  and 
second  portions  of  the  subclavian,  which  under  the  conditions  present 
can  scarcely  be  ligated,  the  success  of  this  method  is  not  so  great  as  it 
might  otherwise  be. 

The  common  carotid  is  now  ligated  mainly  for  aneurysm  or  wound  of 
the  artery  itself.  The  external  or  internal  carotid,  instead  of  the  common 
carotid,  is  now  ligated  to  check  hemorrhage  from  their  branches  due  to 
wounds,  to  prevent  hemorrhage  in  the  removal  of  neoplasms,  and  to 
check  the  growth  of  the  latter.  As  the  ligation  of  the  common  carotid 
has  been  followed  by  cerebral  symptoms  (hemiplegia,  cerebral  softening, 
etc.),  in  about  25  per  cent,  of  the  cases  the  temporary  control  of  the 
vessel  by  a  clamp  tightened  only  enough  to  stop  the  circulation  has  been 
employed  to  prevent  hemorrhage  in  extensive  operations  on  the  head  and 
neck.  The  common  carotid  may  be  secured  at  any  part  in  the  neck,  but 
the  place  of  election  is  just  above  the  omohyoid,  where  it  is  superficial, 
being  covered  only  by  the  skin,  platysma,  and  superficial  and  middle 
layers  of  the  deep  cervical  fascia. 

The  incision  is  carried  along  the  anterior  border  of  the  stemomastoid, 
with  the  centre  opposite  the  cricoid  cartilage.  A  communicating  vein 
between  the  facial  and  the  anterior  jugular  veins  may  be  met  with  in  the 
line  of  incision.  After  incising  the  superficial  layer  of  the  cervical  fascia 
along  the  anterior  border  of  the  stemomastoid,  we  meet  the  omohyoid 
crossing  obliquely  the  line  of  incision  at  the  level  of  the  cricoid  cartilage. 
Then,  incising  the  middle  layer  of  the  cervical  fascia  above  the  omohyoid 
in  the  same  line,  we  expose  the  carotid  sheath,  which  is  here  crossed  by 
the  stemomastoid  artery  and  sometimes  by  the  superior  thyroid  veins. 
The  middle  thyroid  veins  may  also  cross  it  here,  but  usually  under  the 
omohyoid  muscle.  A  valuable  guide  to  the  artery,  about  the  crossing 
point  of  the  omohyoid,  is  the  carotid  tubercle  or  anterior  tubercle  of  the 
sixth  cervical  vertebra,  directly  over  which  lies  the  artery  and  against 
which  it  may  be  compressed,  without  compressing  the  vertebral,  which 
here  occupies  its  bony  canal. 

This  tubercle  serves  also  as  a  guide  to  the  vertebral  artery,  which  lies 
on  the  transverse  process  of  the  seventh  cervical  vertebra  just  below  it, 
crossed  by  the  inferior  thyroid  artery  and,  on  the  left  side,  by  the  thoracic 
duct.  It  is  less  often  tied  than  formerly.  Below  the  omohyoid  the  carotid 
artery  lies  more  and  more  deeply,  as  we  follow  it  to  the  base  of  the  neck, 
being  overlapped  in  front  by  the  sternohyoid  and  sternothyroid  muscles 
and  to  some  extent  by  the  thyroid  body,  especially  if  the  latter  is  enlarged. 
The  inferior  thyroid  artery  and  the  recurrent  laryngeal  nerve  cross 
behind  it.  Near  its  lower  end  the  anterior  jugular  vein  crosses  in  front 
of  it. 

The  carotid  sheath,  derived  from  the  deep  layer  of  the  deep  cervical 
fascia,  encloses  the  internal  jugular  vein  and  the  vagus  nerve  in  addition 
to  the  artery.  The  sheath  should  be  opened  from  the  inner  side  to  avoid 
the  thin-walled  vein,  which  is  external  and,  being  nearly  twice  the  size 
of  the  artery,  overlaps  the  latter  anteriorly.  On  the  right  side  the  vein, 
which  is  commonly  larger  than  that  on  the  left,  becomes  a  little  separated 


PLATE  VIII 


FIG.  52 


HYPOGLOSSAL    NERVE 
GREAT    HORN    OF    HYOID 


SUPERIOR    LARYNGEAL 
NERVE 
EXTERNAL    CAROTID 
ARTERY 


EXTERNAL   JUGULAR 
VEIN 


SCALENUS    AN- 
TERIOR 
STERNO-CLEIOO- 
MASTOIO 

SUBCLAVIAN 
ARTERY 
BRACHIAL 
PLEXUS 


Surgical  Relations  of  the  External  Carotid,  Lingual,  Facial, 
Occipital,  Subclavian,  and  Transverse  Cervical  Arteries. 
'  Kocher. ) 


THE  NECK  141 

from  the  artery  at  the  root  of  the  neck,  while  on  the  left  side  the  vein 
overlaps  the  artery  still  more  at  this  point.  Although  each  of  the  three 
occupants  of  the  sheath  has  its  own  special  investment,  there  is  danger 
of  wounding  the  vein  in  passing  the  aneurysm  needle,  and  to  avoid  this 
danger  the  latter  is  passed  from  without  inward,  after  carefully  separating 
the  vein  and  arterv  and  taking;  care  not  to  include  the  vagus  nerve. 

In  exposing  the  sheath  of  the  carotid  the  descendens  noni  nerve  is 
found  in  front  of  it,  inclining  gradually  from  the  outer  to  the  inner 
side.  Care  should  be  taken  to  avoid  it,  as  it  supplies  the  infrahyoid 
muscles.  It  is  sometimes  found  within  the  sheath.  On  the  inner  side  of 
the  artery  close  to  its  bifurcation  is  a  small,  ovoid,  brownish-red  body, 
5  to  7  mm.  long,  known  as  the  carotid  body.  It  contains  many  nerve 
fibers  and  cells  and  is  closely  associated  with  the  sympathetic  system.  It 
may  be  the  starting  point  of  a  malignant  newgrowth,  especially  of  the 
variety  known  as  perithelioma. 

As  before  stated,  the  external  carotid  is  now  ligated  for  many  condi- 
tions for  which  the  common  carotid  was  formerly  tied.  Thus  it  is  ligated 
for  wound  or  aneurysm  of  its  branches,  but  it  is  better  to  tie  both  ends  of 
bleeding  vessels,  as  the  anastomosis  with  the  branches  of  the  opposite 
external  carotid  is  very  free.  It  is  also  ligated  as  a  preliminary  measure 
in  certain  operations  (like  excision  of  the  parotid,  maxilla,  etc.)  and  as 
a  palliative  measure  in  malignant  neoplasms  to  starve  them  or  prevent 
hemorrhage.  For  the  latter  purposes  excision  is  more  effective  than 
ligature.  In  this  operation  the  branches  are  divided  between  two  liga- 
tures; a  ligature  is  applied  at  its  lower  end  and  as  high  up  as  the  cir- 
cumstances of  the  case  permit,  and  the  portion  between  these  ligatures 
removed.  Ligature,  and  especially  excision,  of  the  external  carotid  is  less 
easy  but  safer  and  more  satisfactory  than  ligature  of  the  common  carotid. 

The  line  of  the  external  carotid  inclines  forward  from  the  line  of  the 
sternomastoid  to  reach  a  point  beneath  the  angle  of  the  jaw.  7//  the 
natural  'position,  when  the  angle  of  the  jaw  about  touches  the  sterno- 
mastoid, the  line  of  the  artery  nearly  corresponds  to  the  anterior  border 
of  the  muscle,  but  in  the  extended  position  of  the  head,  in  which  the 
operation  is  done,  the  line  of  the  artery  is  from  the  angle  of  the  jaw  to 
i  In-  sternomastoid  at  the  upper  border  of  the  thyroid  cartilage. 

Tlic  incision  for  ligature  or  excision  may  be  made  in  this  line  or  across 
it,  in  the  line  of  Kocher's  normal  incision  (p.  138).  In  its  lower  pari 
the  artery  is  comparatively  superjici(d,  being  covered  by  the  same  layers 
which  cover  the  upper  part  of  the  common  carotid  (p.  140),  but  it  soon 
becomes  more  deeply  placed  and  passes  beneath  (he  digastric  and  stylo- 
hyoid muscles  and  then  internal  to  and  within  the  parotid  gland.  Below 
the  digastric,  which  crosses  it  about  3  cm.  (1  [  in.)  above  its  commence- 
ment, it  is  crossed  by  the  hypoglossal  nerve  and  below  this  by  the  facial 
and  lingual  veins,  usually  as  a  common  trunk,  which  is  often  joined  by 
the  superior  thyroid  vein.  The  place  of  election  for  ligature  is  between 
the  superior  thyroid  and  the  lingual  branches,  or  opposite  the  tip  of  the 
greal  cornu  of  the  hyoid  bone.  Through  the  same  incision  the  six  lower 
branches  oi  the  external  carotid  can  beligated&i  their  origin. 


142  THE  HEAD  AND  NECK 

In  the  first  part  of  its  course  the  external  carotid  is  situated  internal 
(mesial)  and  anterior  to  the  internal  carotid,  in  the  loose  connective 
tissue  in  which  both  are  lodged,  hence  the  question  may  arise  whether 
the  vessel  exposed  is  the  internal  or  external  carotid.  The  following 
points  help  us  to  distinguish  the  external  carotid:  (1)  the  presence  of 
branches;  (2)  the  stoppage  of  pulsation  in  its  branches  from  compres- 
sion of  the  artery;  (3)  contact  with  the  hypoglossal  nerve  which  crosses 
it  just  below  the  origin  of  the  occipital  branch;  and  (4)  its  near  relation 
to  the  great  comu  of  the  hyoid. 

In  passing  the  aneurysm  needle  care  is  needed  to  avoid  the  superior 
laryngeal  nerve  which  passes  beneath  the  artery  in  this  situation.  The 
artery  may  also  be  tied  beneath  or  above  the  digastric,  but  it  lies  deeper 
above  the  muscle  and  is  more  difficult  to  expose.  Some  distance  above 
the  muscle  the  glossopharyngeal  nerve  passes  obliquely  beneath  the 
artery.  For  the  various  anomalies  and  variations  of  the  external  carotid 
descriptive  text-books  may  be  consulted,  but  one  may  be  mentioned 
which  I  have  met  with  in  a  preliminary  ligature  of  this  vessel,  i.  e.,  the 
absence  of  an  external  carotid  trunk  and  the  giving  off  of  the  branches 
in  an  axis  manner. 

The  internal  carotid  may  be  exposed  and  ligated  in  much  the  same 
manner  and  with  the  same  precautions  as  the  common  carotid,  of  which 
it  appears  to  be  the  continuation  as  to  its  course  and  relations.  What 
has  been  said  above  as  to  the  relations  of  the  common  carotid  and  its 
branches  is  equally  and  more  frequently  useful  in  the  numerous  opera- 
tions for  various  conditions  in  which  these  vessels  are  exposed  and 
avoided,  as  in  tuberculous  lymphadenoma  of  the  neck,  etc. 

The  internal  jugular  and  the  other  large  veins  of  the  neck,  as  well  as 
the  subclavian  and  axillary  veins,  are  subject  to  the  respiratory  wave  (or 
venous  pulse).  This  is  indicated  by  their  being  more  or  less  emptied  in 
inspiration  and  distended  in  expiration,  and  is  due  to  the  alternately 
decreased  and  increased  intrathoracic  pressure  acting  on  the  right  heart 
and  the  venous  trunks.  When  one  of  these  veins  is  wounded  it  may  be 
prevented  from  completely  collapsing  by  its  attachment  to  the  deep 
fascia,  and  air  is  liable  to  be  drawn  in  during  the  inspiratory  aspiration 
of  its  contents,  provided  the  wound  is  dry  or  the  vein  is  not  immediately 
compressed  between  the  wound  and  the  heart.  Nothing  prevents  the 
passage  of  this  air  to  the  right  auricle  of  the  heart.  Hence  pressure 
should  be  at  once  made  at  the  wound  of  the  vein  or  on  its  cardiac  side. 
The  danger  of  aspiration  of  air  into  veins  has  been  much  exaggerated,  and 
it  is  not  so  frequent  an  accident  as  is  generally  supposed,  and  as  might  be 
expected  from  the  above.  It  is  not  likely  to  happen  if  the  peripheral  flow 
of  blood  to  the  wounded  spot  is  unobstructed,  for  then  the  blood  covers 
the  opening  in  the  vein,  or  if  the  wall  of  the  vein  is  healthy  and  its  wound 
is  not  held  open,  for  then  atmospheric  pressure  causes  it  to  collapse.  It  is 
favored  by  the  elevation  of  the  wounded  part  and  it  may  occur  beyond  the 
limits  of  the  venous  pulse.  Large  amounts  of  air  aspirated  may  cause  death 
rapidly  by  overdistention  and  paralysis  of  the  right  heart,  or  more 
slowly  by  asphyxia  from  air  embolism  of  the  pulmonary  vessels.  The 
entrance  of  smaller  quantities  of  air  is  usually  recovered  from. 


THE  NECK  143 

Phlebitis  and  thrombosis  of  the  internal  jugular  may  occur  secondary 
to  infective  intracranial  sinus  thrombosis  and  call  for  ligation  of  the  vein 
to  prevent  infective  emboli  reaching  the  lungs.  The  vein  may  also  be 
excised  with  impunity  when  it  is  essential  to  the  thorough  removal  of  a 
malignant  growth  or  the  lymph  nodes,  secondary  to  such  a  growth  else- 
where, adherent  to  the  vein.  After  ligation  of  the  vein  the  blood  from 
that  side  of  the  head  passes  through  the  transverse  sinuses  to  the  internal 
jugular  of  the  opposite  side. 

The  cervical  portion  of  the  sympathetic  gangliated  cord  lies  close  behind 
the  carotid  sheath  and  in  front  of  the  prevertebral  fascia.  It  lies  slightly 
internal  to  the  vagus  nerve,  which  is  within  the  sheath,  more  behind  the 
artery.  It  consists  of  three  composite  ganglia  united  by  intervening  nerve 
cords. 

The  superior  cervical  sympathetic  ganglion,  2.5  to  3.75  cm.  (1  to  H  in.) 
long,  lies  in  front  of  the  second  and  third  cervical  transverse  processes. 
It  is  connected  above  with  the  carotid  and  cavernous  plexuses,  below 
with  the  smaller  middle  or  thyroid  ganglion,  situated  where  the  cord  crosses 
in  front  of  and  behind  the  inferior  thyroid  artery,  at  the  level  of  the  sixth 
cervical  vertebra.  The  middle  is  connected  with  the  inferior  ganglion 
by  cords  which  pass  both  behind  and  in  front  of  the  subclavian  artery. 
The  inferior  ganglion,  larger  than  the  middle,  is  deeply  placed  between 
the  seventh  cervical  transverse  process  and  the  neck  of  the  first  rib, 
behind  the  vertebral  artery. 

As  far  as  we  now  know  the  functions  of  the  cervical  sympathetic,  it 
contains  dilator  fibers  of  the  pupil,  motor  fibers  of  the  involuntary 
muscles  of  the  orbit  and  eyelid,  vasomotor  fibers  of  the  head,  neck,  and 
face,  accelerator  fibers  of  the  heart,  besides  secretory  fibers  of  the  salivary 
glands.  Paralysis  of  the  cervical  sympathetic,  as  after  resection  of  the 
ganglia,  causes  contraction  of  the  pupil,  ptosis,  recession  of  the  eyeball, 
congestion  of  the  face,  head,  and  neck,  with  increase  of  tears,  nasal 
mucus,  saliva,  and  sometimes  of  perspiration,  and  decrease  in  the 
pulse  rate.  Many  of  these  symptoms  are  temporary.  Irritation  of  the 
nerve  causes  an  opposite  condition.  From  theoretical  considerations 
the  excision  of  the  superior  or  all  the  cervical  ganglia  has  been  proposed 
for  glaucoma,  exophthalmic  goitre,  epilepsy,  and  tic  douloureux. 

The  superior  ganqlion  alone  requires  removal  for  glaucoma,  and  it  is 
followed  by  contraction  of  the  pupil,  retraction  of  the  globe,  some  ptosis, 
and  the  diminution  of  the  ocular  pressure  (see  p.  78).  The  contraction  of 
the  pupil  is  temporary,  lasting  only  a  few  days,  the  ptosis  is  permanent. 
As  the  superior  ganglion  supplies  the  vasoconstrictors  of  the  carotid 

region  only,  the  inferior  ganglion,  which  does  the  same  for  (he  region  of  the 
vertebral  artery,  must  also  be  removed  to  alter  the  cerebral  circulation  in 
epilepsy  a.n6  improve  the  nutrition  of  the  brain,  by  substituting  hyperemia 

for  anemia.     The  results  in  epilepsy  have  not  been  very  satisfactory.     For 

exophthalmic  goitre  the  resection  of  the  superior  ganglion  for  exoph- 
thalmos and  the  middle  and  inferior  for  the  goitre  and  tachycardia  have 
given  some  encouraging  results.  Hence  for  epilepsy  and  Graves' disease 
the  resection  <>f  the  entire  cervical  sympathetic  is  advisable,  but  from  die 


144  THE  HEAD  AND  NECK 

anatomical  relations  above  given  it  is  evident  that  the  operation  on  the 
middle  and  inferior  ganglia  is  one  of  some  delicacy.  The  cervical  sym- 
pathetic may  be  exposed  by  an  incision  along  the  anterior  or  posterior 
border  of  the  sternomastoid  more  readily  than  might  be  supposed. 
Unilateral  division  of  the  vagus  nerve  may  be  made  without  danger  to 
life,  or  even  without  disturbance  to  the  patient  if  the  nerve  is  first  blocked 
by  cocaine  or  a  preliminary  hypodermic  of  atropine  is  given  to  prevent 
the  inhibitory  action  on  the  heart. 

The  Hyoid  Bone. — Fracture  of  this  is  rare,  but  it  may  occur  in  hanging 
or  from  blows,  falls,  throttling,  or  even  muscular  action.  Its  usual 
situation  is  at  or  near  the  junction  of  the  great  cornu  with  the  body  of 
the  bone.  Movement  of  the  fragments  causes  pain,  hence  this  is  felt  on 
speaking,  swallowing,  opening  the  mouth,  moving  the  tongue,  or  on 
pressure,  as  most  of  the  extrinsic  muscles  of  the  tongue  and  the  depres- 
sors of  the  jaw  are  attached  to  it.  It  is  not  often  serious  of  itself,  but  its 
associated  injuries  may  be  fatal. 

Extending  between  the  upper  border  of  the  thyroid  cartilage  and 
the  upper  and  posterior  margin  of  the  hyoid  bone  is  the  thyrohyoid 
membrane,  about  3  to  4  cm.  (1^  to  If  in.)  in  height.  Owing  to  its  attach- 
ment to  the  superior  border  of  the  hyoid,  the  larynx  may  be  drawn  up 
behind  the  latter  bone.  In  front  of  the  membrane,  between  it  and  the 
back  of  the  body  of  the  hyoid  bone  and  extending  somewhat  below  the 
middle  of  the  latter,  is  the  thyrohyoid  bursa,  which  when  cystic  forms  a 
median  tumor  just  beneath  the  hyoid.  If  this  should  be  opened,  as  in 
case  of  suppuration,  a  fistula  is  likely  to  result  unless  the  lining  membrane 
has  been  excised  or  destroyed,  for  the  constant  movements  of  the  parts  in 
swallowing  prevent  the  walls  of  the  cyst  from  adhering  together.  A 
similarly  placed  cyst  or  fistula,  but  lined  with  columnar  epithelium,  is 
due  to  the  persistence  of  the  thyroglossal  duct.  Mesially  the  membrane 
is  subcutaneous  except  for  the  intervening  cervical  fascia,  laterally  it  is 
covered  by  the  thyrohyoid  and  sternohyoid  muscles. 

Behind  the  thyrohyoid  membrane,  and  separating  it  from  the  epi- 
glottis, is  a  mass  of  fatty  connective  tissue  limited  superiorly  by  the  mucous 
membrane  at  the  base  of  the  tongue.  Through  this  tissue  and  the 
thyrohyoid  membrane  the  transverse  incision  is  carried  in  subhyoid 
pharyngotomy,  keeping  close  beneath  the  hyoid  bone  to  avoid  the  superior 
laryngeal  nerve  (internal  branch),  which  pierces  the  membrane  on  each 
side.  As  this  is  the  sensory  nerve  of  the  larynx,  wounding  it  increases  the 
risk  of  foreign  substances  passing  into  and  through  the  larynx,  which 
involves  the  danger  of  aspiration  pneumonia.  By  this  operation  we  may 
expose  and  operate  upon  the  larynx  above  the  vocal  cords,  especially 
posteriorly,  and  the  lower  part  of  the  pharynx. 

It  is  through  this  thyrohyoid  membrane  and  its  over-  and  underlying 
parts  that  cut-throat  wounds  are  most  likely  to  occur.  In  such  cases  the 
anterior  jugular  vein,  superior  thyroid  artery  and  nerve,  and,  if  near  the 
hyoid  bone,  perhaps  the  lingual  artery,  would  be  divided,  besides  several 
muscles,  etc.  In  a  deep  wound  the  pharynx  would  be  opened  and  the 
epiglottis  cut  near  its  base.    The  latter  are  serious  complications,  for  the 


THE  NECK  j  45 

free  end  of  the  epiglottis  may  obstruct  the  glottis  and  the  blood  flowing 
into  the  larynx  and  trachea  may  also  cause  asphyxia.  Suicidal  throat 
wounds  made  by  right-handed  persons  are  generally  oblique,  passing 
from  the  left  downward  and  to  the  right,  and  the  first  part  of  the  wound 
is  often  shallow.  If  the  wound  be  above  the  hyoid  bone,  the  anterior 
jugular  vein,  lingual  artery,  branches  of  the  facial  artery,  the  hypoglossal 
and  lingual  nerves  and  the  submaxillary  gland,  besides  several  muscles, 
would  be  cut.  Among  the  divided  muscles  those  attaching  the  tongue  to 
the  jaw,  are  likely  to  be  cut  so  that  the  tongue  is  liable  to  fall  back  upon 
the  larynx  and  cause  suffocation.  The  tongue  itself  may  be  cut  and  the 
floor  of  the  mouth  freely  opened. 

Next  in  frequency  to  wounds  in  the  thyrohyoid  space  are  those  involv- 
ing the  trachea  or  larynx,  in  which  the  anterior  jugular  vein,  thyroid 
gland,  superior  and  inferior  thyroid  arteries  and  veins,  middle  thyroid 
veins,  recurrent  laryngeal  nerves,  trachea  and  esophagus,  besides  the 
infrahyoid  muscles,  are  cut.  There  is  danger  of  blood  getting  into  the 
trachea  and  bronchi  in  sufficient  quantity  to  produce  suffocation.  When 
the  trachea  is  severed  or  widely  opened  the  voice  is  lost. 

In  all  such  wounds  of  the  neck,  suicidal  or  otherwise,  the  great  vessels 
often  escape  in  a  surprising  manner,  being  protected  in  part  by  their 
depth  and  mobility,  and  in  part  by  the  projecting  thyroid  cartilages 
and  by  the  contraction  of  the  stemomastoid  muscle  pressing  the  vessels 
back.  Of  course,  in  some  cases  the  great  vessels  are  wounded,  usually 
with  a  rapidly  fatal  result.  In  some  cases  of  gunshot  and  punctured 
wounds  the  vessels  seem  to  have  been  pushed  aside  and  to  have  owed 
their  safety  to  their  mobility.  The  great  vessels  are  more  easily  wounded 
in  wounds  across  the  cricothyroid  space  or  the  upper  part  of  the  trachea 
than  in  wounds  made  elsewhere  in  the  neck  with  equal  force.  Some 
wounds  at  the  side  of  the  neck  have  involved  a  large  part  of  the  brachial 
plexus  without  other  important  structures.  The  chief  dangers  of  wounds 
of  the  neck  are  hemorrhage  and  suffocation,  the  latter  from  blood  in  the 
trachea  and  bronchi  or  from  obstruction  of  the  glottis  by  the  falling  back 
of  the  tongue  or  the  wounded  epiglottis. 

The  Larynx. — The  larynx  in  its  median  position  below  the  thyro- 
hyoid membrane  can  usually  be  readily  felt,  especially  in  males  in  whom 
it  is  larger,  so  that  it  stands  out  between  the  two  sternomastoids.  The 
most  prominent  part  is  the  anterior  mesial  border  of  the  thyroid  cartilage, 
2  to  3  cm.  (|  to  1 1-  in.)  in  height,  whose  upper  angle  is  known  as  the 
pomum  Adami  or  Adam's  apple.  A  bursa  has  been  described  in  front 
of  this  prominence  by  Beehard.  In  women  and  children,  in  whom  the 
Deck  is  more  rounded  and  the  larynx  is  smaller,  the  latter  is  less  promi- 
nent but  is  usually  distinctly  felt,  and  is  an  important  landmark. 

Tin-  relative  position  of  the  larynx  varies  with  the  position  of  the  neck 
and  the  age  of  the  patient.  Thus  the  lower  border  of  the  cricoid  cartilage 
■  ;i  riea  from  a  point  opposite  the  fifth  to  one  opposite  the  seventh  cervical 
Vertebra,  being  higher  in  the  young  and  when  the  neck  is  extended.  In 
the  mi, linn  line  the  larynx  is  covered  only  by  the  skin  and  cervical  fascia 
(the  anterior  and  middle  layers  blended  into  one),  laterally  by  the  infra- 
10 


146 


THE  HEAD  AND  NECK 


hyoid  muscles  and  the  thyroid  gland.  The  superior  aperture  of  the  larynx 
or  the  space  between  the  aryteno-epiglottic  folds  corresponds  to  the 
superior  border  of  the  thyroid  cartilage,  the  glottis  to  the  junction  of  the 
superior  and  middle  thirds  of  its  anterior  border,  the  laryngeal  pouches 
to  about  its  superior  third. 

With  the  laryngoscope  may  be  seen  (Fig.  53)  the  triangular  superior 
aperture  of  the  larynx  placed  very  obliquely  from  above  and  in  front  down- 
ward and  backward.  Its  base  is  at  the  epiglottis  in  front,  its  sides  are 
formed  by  the  aryteno-epiglottic  folds,  in  which  are  two  eminences  corre- 
sponding to  the  cornicula  and  cuneiform  cartilages,  and  its  apex  is  at  the 
arytenoid  commissure  of  mucous  membrane.  Between  each  aryteno- 
epiglottic  fold  and  the  ala  of  the  thyroid  cartilage  is  the  shallow  depres- 
sion of  the  pyriform  sinus,  in  which  small  foreign  bodies  are  frequently 
lodged.  More  deeply  are  seen  the  superior  or  false  and  the  inferior  or 
true  vocal  cords  with  the  ventricle  between  the  two  pairs  of  cords.  Below 
the  glottis  a  little  of  the  cricoid  cartilage  and  more  or  less  of  the  anterior 

Fig.  53 


EPIGLOTTIS 


ARYTENO-EPI- 
GLOTTIC   FOLD 
FYRIFORM    POUCH 
CARTILAGE    OF 

WRISBERG 
CARTILAGE    OF 

SANTORIND 


FALSE    VOCAL 

CORD 
VENTRICLE 
TRUE    VOCAL 


ARYTENOID 
COMMISSURE 


Larynx  viewed  from  above,  the  vocal  cords  and  arytenoid  cartilages  widely  separated. 

(Zuckerkandl.) 


tracheal  wall  is  visible,  and,  if  the  glottis  is  widely  dilated,  even  the 
bifurcation  of  the  trachea  may  be  dimly  seen.  As  the  mirror  is  tilted,  the 
image  of  the  epiglottis  is  on  its  upper  and  anterior  part,  that  of  the  ary- 
tenoids on  the  lower  and  posterior  part,  but  that  of  either  vocal  cord  is 
on  the  side  to  which  it  actually  belongs. 

The  glottis  (Figs.  47,  53)  is  the  narrowest  part  of  the  interior  of  the 
larynx,  measuring  nearly  2.5  cm.  (1  in.)  anteroposteriorly  in  the  adult 
male,  and  about  three-fourths  of  that  in  the  female  and  in  the  male 
before  puberty.  Approximately  the  anterior  two-thirds  of  the  glottis 
consists  of  the  true  vocal  cords,  the  posterior  third  of  the  interval  between 
the  arytenoid  cartilages,  covered  by  mucosa.  The  transverse  diameter 
may  equal  half  its  length  in  extreme  dilatation.  These  dimensions  are 
important  in  relation  to  the  arrest  of  foreign  bodies  and  the  introduction 
of  instruments. 

On  account  of  its  narrow  caliber,  foreign  bodies  of  the  most  varied 
character  may  be  arrested  here,  either  above  or  in  the  rima  of  the  glottis, 


THE  NECK  147 

according  to  their  size.  I  have  removed  from  a  one-year-old  baby 
through  a  high  tracheotomy  two  pieces  of  egg  shell  which  were  caught 
in  the  glottis  and  hung  down  below  it.  The  mucosa  of  the  larynx,  supplied 
by  the  superior  laryngeal  nerve,  is  so  sensitive  that  it  acts  as  a  sentinel, 
at  whose  warning  the  glottis  closes  to  keep  out  foreign  bodies,  but  it  is 
sometimes  taken  unawares  and  lets  a  foreign  body  through  into  the 
trachea.  The  danger  of  many  such  foreign  bodies  in  the  larynx  or  trachea 
is  not  so  much  due  to  the  mechanical  obstruction  as  to  the  reflex  spasm, 
of  the  glottis  which  they  excite. 

A  peculiar  spasm  of  the  glottis  of  reflex  nervous  origin,  perhaps  due 
to  indigestible  food,  dentition,  or  spinal  disease,  occurs  in  infancy  under 
the  name  of  laryngismus  stridulus  or  laryngeal  asthma.  A  similar  condi- 
tion of  spasm  of  the  glottis  in  adults  may  be  due  to  the  pressure  of  an 
aneurysm  or  a  tumor  on  the  recurrent  laryngeal  nerve.  Such  pressure 
in  time  paralyzes  the  nerve  so  that  the  vocal  cord  on  the  affected  side 
cannot  be  approximated,  and,  consequently,  the  voice  is  hoarse  or  lost, 
a  characteristic  symptom  of  many  aneurysms  of  the  aortic  arch.  The 
opposite  cord  may,  however,  be  made  to  reach  beyond  the  median  line 
in  the  effort  at  compensation. 

The  caliber  of  the  rvma  glottidis  may  be  diminished  as  the  result  of 
strictures  from  syphilitic,  tuberculous,  or  diphtheritic  ulceration  which 
require  the  long-continued  use  of  an  intubation  tube  or  sometimes  a 
more  radical  operation. 

The  shape  of  the  glottis  varies  from  an  extremely  narrow  vibrating 
slit,  in  the  production  of  a  high  note,  to  an  elongated  narrow  triangle 
with  the  apex  forward,  in  quiet  breathing,  or  a  lozenge-shaped  figure 
with  a  truncated  posterior  angle  in  deep  respiration.  These  changes 
are  due  to  the  approximation  or  separation  of  the  sides  of  the  glottis  by 
means  of  the  approximation  or  separation  of  the  arytenoid  cartilages, 
and,  in  the  production  of  the  wider  lozenge-shaped  opening,  by  the 
rotation  of  their  anterior  angles,  to  which  the  vocal  cords  are  attached. 
The  glottis  is  closed,  after  inspiration,  to  fix  the  diaphragm  in  efforts  of 
expulsion,  as  in  defecation,  urination,  vomiting,  and  parturition. 

The  mucosa  of  the  true  vocal  cords  is  covered  by  a  thin  stratified 
epithelium,  beneath  which  there  is  no  loose  submucous  connective  tissue, 
hence  there  is  little  or  no  chance  of  acute  edema  of  the  glottis.  The 
so-called  "edema  of  the  glottis"  occurs  in  the  submucous  tissue  above 
the  glottis,  especially  in  thai  of  the  aryteno-epiglottic  folds,  which  is  very 
abundant.  This  may  rapidly  swell  in  case  of  laryngitis  or  irritation  by 
heat,  caustics,  injury,  or  neighboring  inflammatory  conditions,  and  cause 

obstruction  of  the  superior  aperture  of  the  larynx,  with  dyspnea  or  even 

luflbcation,  especially  in   children    in    whom   the   larynx  is  small.     The 

mucosa  is  thickest  and  the  submucosa  most  abundant  iii  the  aryteno- 
epiglottic  folds,  the  ventricles,  the  false  voeal  cords,  and  the  under  Surface 
of  the  epiglottis,  in    the  order  given,  and   the  degree  of  congestion  and 
lling  in   acute  laryngitis  varies  correspondingly.     The  result   of  the 
lling  i-  a   CTOUpy  COUgfa  and  hoar  eneSS  or  aphonia,  with  dyspnea   in 
from    obstruction    Or   spasm.      In    some   cases    the   swelling 


148  THE  HEAD  AND  NECK 

affects  chiefly  the  parts  below  the  glottis.  To  relieve  the  extreme  dyspnea 
due  to  edema  of  the  glottis  or  the  presence  of  false  membrane,  etc., 
intubation  is  very  effective. 

Laryngeal  polypi  of  various  kinds,  either  pedunculated  or  sessile,  may 
grow  on  the  vocal  cords  or  other  parts  of  the  larynx  and  cause  aphonia, 
cough,  and  more  or  less  difficulty  in  breathing.  They  may  be  removed 
through  the  mouth,  with  the  aid  of  the  laryngoscope,  through  a  subhyoid 
pharyngotomy  or  by  thyrotomy .  The  latter  consists  of  a  median  splitting 
of  the  thyroid  cartilage,  which  must  be  done  exactly  in  the  median  line 
so  that  the  opening  into  the  larynx  shall  be  between  the  vocal  cords, 
otherwise  there  is  great  danger  of  permanently  impairing  vocalization. 
This  operation  may  also  be  applied  to  the  removal  of  impacted  foreign 
bodies  and  infrequent  subglottic  growths,  to  the  treatment  of  some  forms 
of  stenosis,  and  to  exploration  in  intralaryngeal  growths. 

The  thyroid,  cricoid,  and  arytenoid  cartilages  are  composed  of  hyaline 
cartilage,  and,  like  other  structures  composed  of  this  variety  of  cartilage, 
are  liable  to  ossification,  especially  in  males  after  middle  life.  It  occurs 
first  in  the  thyroid  and  cricoid  cartilages,  commences  near  their  articu- 
lation, and  renders  the  larynx  more  liable  to  fracture.  The  latter  occurs 
from  lateral  or  anterior  compression  by  blows,  falls,  throttling,  etc. 
Fracture  is,  therefore,  more  common  in  the  thyroid  cartilage  and  in  males 
on  account  of  its  size,  shape,  and  prominence.  The  thyroid  cartilage  is 
commonly  fractured  at  or  near  the  median  line.  According  to  Dr. 
Rambaud,  the  line  of  fracture  is  usually  to  one  side  of  the  median  line, 
owing  to  the  fact  that  the  two  alae  of  the  thyroid  are  united  in  front  by  a 
thin  median  strip  of  cartilage,  at  whose  junction  with  one  of  the  alse  the 
fracture  occurs.  Fracture  of  the  cricoid  is  less  common  and  more  serious, 
as  it  requires  more  violence.  Fracture  of  the  larynx  is  dangerous  on 
account  of  the  liability  to  dyspnea  due  to  the  aspiration  of  blood,  spasm 
of  the  glottis,  displacement  of  the  fragments,  and  edema  of  the  glottis. 
Hence  in  most  cases  tracheotomy  should  be  promptly  done.  Owing  to 
the  fact  that  the  larynx  moves  in  deglutition,  this  act  is  very  painful  in 
laryngeal  fracture.  The  epiglottis,  like  other  elastic  cartilages,  is  not 
liable  to  ossification,  but  it  is  a  favorite  site  for  syphilitic  ulceration.  Peri- 
chondritis may  involve  the  cricoid  and,  less  often,  the  thyroid  cartilages 
as  a  sequel  to  typhoid  fever  or  secondary  to  tuberculous  or  cancerous 
ulceration. 

Excision  of  the  larynx  is  sometimes  done  for  malignant  disease.  After 
exposure  by  a  free  median  incision  the  larynx  is  freed  laterally  from  the 
sternothyroid  and  thyrothyoid  muscles  and  more  posteriorly  from  the 
stylo-  and  palatopharyngei  and  the  inferior  constrictor  muscles.  The 
superior  and  inferior  laryngeal  nerves  are  divided,  and  branches  of  the 
like  named  arteries.  Then  severing  it  from  the  trachea  or  the  thyro- 
hyoid membrane  the  larynx  is  separated  from  the  pharynx  and  esophagus 
behind  it,  either  from  below  up  or  above  down,  care  being  taken  not  to 
"button-hole"  the  esophagus.  Occasionally  only  one-half  of  the  larynx 
is  excised.  Aspiration  pneumonia  is  a  great  menace.  Preliminary 
tracheotomy  is  not  necessary,  for  if  the  larynx  is  severed  from  the  trachea 


PLATE   IX 


FIG.  54 


STERNOHYOID 
MUSCLE 


LINGUAL    ARTER 


SUP.   THYROI  D 
ARTERY 


SUP     LARYNGEA 
ARTERY 


YROHYOID 
MEMBRANE 


RICOTHYROID 
ARTERY 


INF     THYROID 
VEINS 


Superficial  Vessels  of  the  Infrahyoid  Region,  around  the 
larynx,  thyroid,  and  trachea.     (Merkel. ) 


f;g.  55 


THYROIC 


COMMON    CAROTID 

ARTERY 
VAGUS     NERVE 
RECURRENT 

LARYNGEAL 

NERVE 

SYMPATHETIC 
GANGLION 


>ltRTEBR/, 


Cross-section  of  Thyroid   Body,  Trachea,  and  Esophagus, 
showing  their  relations.      (Testut.) 


THE  NECK  149 

before  the  air  passages  are  opened  elsewhere  the  distal  end  of  the  trachea 
may  be  brought  forward  and  a  tube  introduced  temporarily. 

Laryngotomy  (cricotomy),  or  the  opening  of  the  larynx  through  the 
cricothyroid  membrane,  is  sometimes  performed  in  place  of  tracheotomy 
on  account  of  the  ease  and  rapidity  of  its  performance.  It  is  not  appli- 
cable to  children  under  puberty  on  account  of  the  narrowness  of  the 
cricothyroid  space,  which  in  the  adult  is  at  most  only  about  12  mm.  ( h  in.) 
in  height.  The  cricothyroid  branches  of  the  superior  thyroid  arteries 
anastomose  across  this  space,  and,  though  usually  small,  they  occasionally 
cause  serious  and  even  fatal  hemorrhage,  which  may  be  obviated  by 
dividing  the  membrane  transversely  or  by  tearing  the  artery  between  two 
forceps.  An  objection  to  the  operation  is  the  proximity  of  the  vocal 
cords,  so  that  it  is  unsuited  for  cases  where  the  tube  is  to  be  worn  for  long. 
In  adults,  in  whom  alone  the  operation  is  applicable,  it  is  not  advisable 
to  divide  the  cricoid  cartilage  to  gain  more  room,  on  account  of  the  pos- 
sibility of  its  being  ossified  and  the  little  added  room  that  it  gives. 

The  lymphatics  of  the  larynx  pass  mostly  to  the  deep  cervical  glands, 
but  in  part  to  a  node  between  the  cricothyroid  muscles,  to  one  in  front  of 
the  trachea,  and  to  several  small  ones  along  the  recurrent  nerve.  Of 
the  nerves  of  the  larynx  the  superior  supplies  sensation  to  the  mucosa 
down  to  the  glottis  and  motor  fibers  to  the  cricothyroid  muscle,  which 
makes  the  cords  tense.  The  arytenoid  muscle  is  supplied  both  by  this 
and  the  recurrent  laryngeal,  which  supplies  all  the  other  muscles.  The 
inferior  laryngeal  also  contains  some  sensory  fibers. 

Trachea. — About  half,  or  5.5  cm.  (2\  in.),  of  the  trachea  is  in  the  neck, 
between  the  cricoid  cartilage,  opposite  the  sixth  cervical  vertebra,  and  the 
episternal  notch.  This  length  varies  with  the  age,  and  the  length  and 
position  of  the  neck.  Thus  in  extension  of  the  neck  it  may  be  increased 
by  2  cm.  (f  in.)  in  its  cervical  portion  and  2.5  cm.  (1  in.)  altogether, 
owing  to  its  elasticity  (Braune).  This  elasticity  allows  it  to  accommo- 
date itself  to  the  movements  of  the  neck,  and  also  causes  the  lower  end  to 
retract  when  it  is  severed.  The  retraction  is  favored  by  the  loose  con- 
nective tissue  in  which  it  lies,  and  this  also  allows  of  considerable  lateral 
mobility.  This  mobility  is  greater  in  children.  It  allows  the  trachea  to 
escape  from  injury  or  the  pressure  of  tumors  on  one  side  of  it,  and  adds 
to  the  difficulties  of  tracheotomy.  As  the  trachea  passes  somewhat 
backward,  as  it  descends  its  upper  part  is  more  superficial;  hence,  when 
possible,  tracheotomy  should  be  performed  here,  for  not  only  is  it  deeper 
but  its  relations  arc  more  complicated  below. 

Relations  of  Overlying  Parts  (Fig.  55).  Above  the  thyroid  isthmus, 
which  lies  in  front  of  the  second,  third,  and  fourth  tracheal  cartilages, 
the  sternohyoid  and  sternothyroid   muscles  are  separated  by  a  slight 

interval,  and    the  superficial   and   middle  layers  of  deep  cervical    fascia 

form  practically  a  single  layer  in  the  median  line.  The  Levator  glandules 
thyroideae  muscle  and  the  pyramidal  lobe  of  the  thyroid  when  present 

|»    152    li<-  in  front  of  (he  trachea.     As  the  thyroid  isthmus  may  leave  nn- 

•  red  above  it  but  a  single  tracheal  ring  it  must  be  retracted  downward 
t  .  allow  a  high  tracheotomy.  To  permit  this  retraction  ftie  fascia  connect- 


150  THE  HEAD  AND  NECK 

ing  it  with  the  cricoid  cartilage  should  be  divided  by  a  transverse  incision 
over  the  latter,  and  then  its  downward  retraction  is  easy.  In  children  the 
thyroid  isthmus  is  little  more  than  connective  tissue,  and  may  be  ignored 
or  divided  between  two  ligatures,  and  the  latter  may  also  be  done  in  the 
adult.  Abnormal  branches  of  the  superior  thyroid  artery  or  twigs  of  it 
to  the  pyramidal  process,  when  present,  may  cross  the  upper  tracheal 
rings,  and  a  communicating  branch  between  the  superior  thyroid  veins 
may  cross  at  the  upper  border  of  the  isthmus. 

Below  the  thyroid  isthmus  the  superficial  and  middle  layers  of  the  deep 
cervical  fascia  are  separated  from  one  another  by  an  interval  filled  with 
loose  connective  tissue  and  fat,  in  which  there  is  a  transverse  anasto- 
mosis between  the  anterior  jugular  veins,  just  above  the  sternum.  Below 
the  thyroid  gland  the  superficial  layer  splits  into  two  layers  attached  to 
the  anterior  and  posterior  borders  of  the  epistemal  notch  and  enclosing 
a  triangular  interval,  so  that  there  are  three  fascial  layers  to  incise  at  this 
level.  Beneath  the  middle  layer  of  the  deep  fascia  is  a  layer  of  fatty 
connective  tissue  in  which  the  plexiform  inferior  thyroid  veins,  the  thy- 
roidea  ima,  when  present,  and,  in  infants  under  two  years  of  age,  the 
upper  1  cm.  of  the  thymus  gland  lie  in  front  of  the  trachea.  At  the  very 
root  of  the  neck  the  left  innominate  vein  crossing  the  trachea  may  extend 
up  above  the  sternum,  especially  when  there  is  venous  congestion  or 
when  the  neck  is  extended,  both  of  which  conditions  are  usually  present 
when  tracheotomy  is  performed.  The  carotids  crossing  the  trachea 
anterolaterally  may  occasionally  overlap  it  in  front  to  an  abnormal 
degree  and  the  left  common  carotid,  when  it  arises  from  the  innominate, 
may  cross  the  trachea  above  the  sternum.  The  infrahyoid  muscles  are 
here  in  close  contact  and  the  trachea  is  more  movable. 

Tracheotomy  is  called  high  or  low  according  as  it  is  above  or  below  the 
isthmus  of  the  thyroid  body.  The  facts  just  recited,  in  addition  to  the 
depth  from  the  surface  and  the  greater  danger  of  bronchopneumonia  and 
of  the  sinking  of  pus  into  the  mediastinum,  make  the  high  operation  always 
to'  be  preferred. 

In  either  operation  the  neck  should  be  fully  extended,  for  this  steadies 
the  trachea,  makes  it  more  superficial,  lengthens  the  neck  and  the  por- 
tion of  the  trachea  in  the  neck,  and  makes  tense  the  structures  in  front. 
The  chin  is  held  in  the  same  longitudinal  line  with  the  episternal  notch 
and  the  incision  is  made  exactly  in  the  median  line.  The  cervical  fascia 
should  be  well  and  freely  divided  to  avoid  the  not  uncommon  accident 
of  passing  the  tube  between  the  fascia  and  the  trachea.  The  trachea 
should  be  steadied  from  above  by  a  sharp  hook  in  the  median  line  as  a 
guide  to  the  latter  and  to  the  opening  when  made.  Cases  are  reported 
where,  from  lack  of  such  precaution,  the  trachea  has  been  opened  from 
the  side  or  behind  or  even  through  the  esophagus  and  where  the  opening 
when  made  could  not  be  readily  found  again.  The  opening  should 
be  made  by  a  thrust  of  the  knife  to  insure  the  penetration  of  the  lining 
mucosa,  to  avoid  the  mistake  of  passing  the  tube  into  the  trachea  between 
the  mucosa  and  the  fibrocartilaginous  framework. 

The  diameter  of  the  trachea  varies  with  the  age  and  to  some  extent 


THE  NECK  151 

individually,  and  is  of  importance  with  reference  to  the  size  of  the  trache- 
otomy tube  to  be  used.  In  the  adult  cadaver  the  greatest  transverse 
diameter  may  vary  between  18  and  25  mm.  (f  to  1  in.),  but  in  the  living 
subject  it  is  less.  According  to  the  observations  of  Symington  and 
(  ruersant  the  following  diameters  of  the  tube  are  suited  to  the  ages  given: 
Under  one  and  one-half  years,  4  mm.;  one  and  one-half  to  two  years, 
5  mm.;  two  to  four  years,  6  mm.;  four  to  eight  years,  8  mm.;  eight  to 
twelve  years,  10  mm.;  twelve  to  fifteen  years,  12  mm.;  adults,  12  to  15  mm. 
The  tube  should  not  be  too  curved  lest  the  pressure  of  its  sharp  end 
cause  an  ulceration  into  the  innominate  vein  or  artery  or  the  common 
carotid  and  occasion  a  fatal  hemorrhage.  I  have  known  of  one  such 
case,  and  several  are  recorded. 

The  difficulties  of  tracheotomy  in  children  depend  upon  the  shortness 
of  the  neck,  the  small  size  of  the  trachea,  its  mobility  and  depth,  the  high 
level  at  which  the  great  vessels  frequently  cross  it,  and  the  occasional 
presence  of  the  thymus  in  front  of  it.  The  full  length  of  the  cervical 
portion  of  the  trachea  in  a  child  of  three  to  five  years  is  about  3.75  cm. 

(1*  in-)- 

The  cartilages  prevent  the  collapse  of  the  tube  from  internal  suction 
and  external  atmospheric  pressure  in  inspiration,  and  from  the  pressure 
of  enlarged  thyroids  and  other  tumors.  Constant  pressure,  as  of  a  large 
goitre,  may  cause  the  gradual  absorption  of  the  rings  beneath  the  area  of 
pressure,  so  that  serious  compression  may  occur  and  a  long,  special  form 
of  tracheal  tube  may  be  required  to  avoid  collapse  of  the  trachea.  Ossi- 
fication of  the  tracheal  cartilages  commences  at  about  forty  to  fifty  years 
of  age.  In  the  child  the  trachea  collapses  on  slight  pressure,  owing  to 
the  yielding  character  of  the  thin  cartilaginous  rings.  Treves  mentions  a 
ca  9e  where  he  saw  the  trachea  of  an  infant  bent  on  itself  and  invaginated 
into  its  lumen  by  the  pilot  of  the  tracheotomy  tube. 

The  musculomembranous  posterior  portion  of  the  tracheal  wall  is  in 
contact  with  the  esophagus,  which  deviates  somewhat  to  the  left  in  the 
lower  part  of  the  neck.  The  absence  of  cartilaginous  rings  between  the 
trachea  and  esophagus  avoids  the  pressure  of  the  trachea  upon  the 
esophagus,  which  might  impede  deglutition.  Impacted  foreign  bodies 
or  malignant  disease  in  the  esophagus  may  cause  serious  difficulty  in 
respiration  by  pressure  on  the  posterior  soft  portion  of  the  tracheal 
wall.  These  two  tubes,  connected  together  by  loose  connective  tissue, 
allow  movements  of  one  upon  the  other  at  the  same  time  that  they  move 
together  in  deglutition.  The  easily  felt  trachea  is  of  great  importance 
B  landmark  in  external  esophagotoniv  in  the  neck.  In  the  angle 
between  them  lie  the  recurrent  laryngeal  nerres,  the  right  being  more 
behind,  the  left    to    (he  side   of   the   trachea. 

The  common  carotid  arteries,  and  the  other  contents  of  (heir  sheaths, 
as  well  as  the  inferior  thyroid  and  the  vertebral  arteries,  are  near  enough 
to  be  said  to  be  in  relation  with  the  trachea  on  the  sides,  mil  are  not  near 
enough  to  disturb  the  operator  in  tracheotomy,  especially  if  he  keep 
tlv  in  the  median  line  and  is  careful  to  (i\  the  trachea  by  a  sharp 
hook  in  thai  line.     In  a  low  I  raeheotoiny  the  great  vessels  are  nearer  the 


152  THE  HEAD  AND  NECK 

sides  of  the  trachea  than  they  are  above  where  the  lobes  of  the  thyroid 
gland  intervene. 

Foreign  bodies  in  the  trachea  are  usually  arrested  at  its  bifurcation,  and 
if  they  pass  beyond  this  it  is  into  the  right  bronchus,  as  a  rule  (see  p. 
251).  They  entail  a  fatal  result  unless  removed  by  coughing  or  by 
operation.  Through  a  low  tracheotomy  they  can  sometimes  be  reached 
and  removed  by  a  long  forceps  as  low  down  as  the  bifurcation,  but  more 
often  they  are  expelled  by  a  violent  fit  of  coughing,  through  the  wound 
or  through  the  glottis,  at  the  time  of  operation  or  subsequently.  They 
may  also  be  removed  through  the  bronchoscope. 

High  tracheotomy,  besides  being  called  for  in  the  case  of  foreign 
bodies  below  or  obstruction  above  it  (in  the  larynx),  is  not  infrequently 
done  as  a  preliminary  operation  in  several  operations  about  the  mouth  and 
neck.  Its  object  is  usually  to  prevent  blood  entering  the  trachea,  and  for 
this  purpose  the  trachea  is  plugged  around  the  tube  by  one  of  the  several 
tampon  cannulse  or  by  small  pieces  of  sponge  or  gauze.  The  same  object 
may  be  attained  without  tracheotomy  by  a  low  position  of  the  head, 
hanging  over  the  end  of  the  table  (Rose's  position).  In  every  trache- 
otomy a  slight  amount  of  blood  enters  the  trachea  when  it  is  opened,  but 
if  it  merely  comes  from  a  venous  oozing  the  latter  soon  ceases  when  the 
air  rushes  into  the  lungs  and  the  right  heart  is  allowed  to  empty  itself. 

The  real  surgical  limit  of  the  trachea  is  the  episternal  notch;  the 
thoracic  part  of  the  trachea  is  described  among  the  contents  of  the  thorax, 
as  is  also  the  entire  esophagus. 

The  Thyroid  Gland  (Fig.  55). — Its  laternal  lobes  extend  from  the  fifth 
or  sixth  tracheal  rings,  18  mm.  (f  in.)  above  the  sternum,  up  to  the 
middle  of  the  thyroid  cartilage.  Their  greatest  dimensions  are  normally 
about  5  cm.  (2  in.)  in  length,  3  cm.  (1^  in.)  in  breadth,  and  18  mm. 
(f  in.)  in  thickness.  When  the  lobes  distinctly  exceed  these  measure- 
ments they  may  be  considered  to  be  enlarged.  They  may  be  temporarily 
enlarged  in  menstruation.  In  infancy  and  in  females  they  are  relatively 
larger  than  in  adults  and  in  males  respectively,  and  the  right  lobe  is  also 
commonly  larger  than  the  left.  It  is  also  noticeable  that  thyroid  enlarge- 
ments (goitre,  bronchocele)  are  more  common  in  females  and  on  the  right 
side.    The  size  of  the  gland  commonly  diminishes  in  late  life. 

The  isthmus  varies  from  6  to  18  mm.  (\  to  f  in.)  in  height  and  lies  in 
front  of  the  second,  third,  and  fourth  tracheal  rings,  but  it  may  extend 
up  to  the  cricoid  and  sometimes  nearly  down  to  the  sternum.  In  infants 
it  is  but  slightly  developed,  which  is  of  advantage  in  tracheotomy.  It  is 
absent  in  10  per  cent,  of  cases.  From  its  upper  margin,  or  the  adjacent 
margin  of  the  left  lobe,  springs  the  'pyramidal  lobe  when  present,  as  it  is 
in  from  80  per  cent.  (Streckeisen)  to  43  per  cent.  (Marshall)  of  cases. 
This  represents  a  remnant  of  the  median  anlage  of  the  thyroid,  the  thyro- 
glossal  duct,  which  in  the  fetus  extends  downward  from  the  foramen 
cecum  on  the  tongue  in  front  of  the  hyoid  bone.  This  duct  occasion- 
ally remains  open  and  gives  rise  to  a  fistula  of  the  neck.  From  it  are 
developed  the  aberrant  or  accessory  thyroids,  not  infrequently  found  in 
the  neighborhood  of  the  hyoid  bone  and  sometimes  behind,  in  front  or 


THE  NECK  153 

even  within  the  larynx  or  trachea.  Other  goitre  nodules  have  become 
secondarily  separated  from  the  rest  of  the  gland  or  goitre,  to  which  they 
remain  connected  by  connective-tissue  bands.  Such  false,  aberrant,  or 
accessory  goitres  may  cause  difficulty  in  diagnosis  and  removal,  as  they 
are  likely  to  become  very  movable,  even  slipping  into  the  mediastinum. 
Deeply  seated  carcinoma  of  the  neck  may  also  have  its  origin  in  them. 

The  relations  of  the  thyroid  are  of  great  importance  in  reference  to 
the  symptoms  of  its  enlargement  and  the  operation  of  excision  or  enu- 
cleation of  such  enlargements.  It  is  covered  in  front  by  the  sternohyoid, 
sternothyroid,  and  omohyoid  muscles  and  overlapped  by  the  anterior 
border  of  the  sternomastoid.  It  lies  beneath  the  superficial  and  middle 
layers  of  the  deep  cervical  fascia.  It  is  enclosed  by  a  fibrous  capsule 
from  whose  inner  and  upper  parts  two  broad  bands,  the  suspensory 
ligaments,  are  continued  inward  and  upward,  to  be  attached  to  the  back 
of  the  cricoid  cartilage.  The  expansion  of  the  fibrous  capsule  from  the 
isthmus  to  the  cricoid  cartilage  is  divided  in  tracheotomy  to  allow  the 
downward  retraction  of  the  isthmus.  This,  the  external  fibrous  capsule  of 
Kocher,  contains  several  veins — venae  accessorial  (Kocher),  also  sensory 
nerves  and  muscle  fibres  and  the  recurrent  laryngeal  nerves.  Hence 
this  capsule  should  be  opened  and  left  behind  in  excision  of  the  gland. 
The  thyroid  is  moulded  to  the  underlying  trachea  and  larynx,  and  is 
attached  to  them  by  fibrous  tissue,  where  it  is  in  contact,  as  well  as  by  the 
suspensory  ligament.  Hence  it  moves  with  them  in  deglutition,  an  impor- 
tant point  in  the  diagnosis  of  bronchocele  from  other  cervical  tumors. 

The  enlarged  thyroid  may  compress  the  trachea,  especially  if  the  enlarge- 
ment is  rapidly  formed,  for  it  is  held  down  by  the  overlying  muscles  and 
the  deep  fascia  which  forms  their  sheaths.  Hence  to  relieve  the  dyspnea 
the  division  of  these  muscles  or  of  the  isthmus  has  been  practised,  but 
often  with  unsatisfactory  results.  In  chronic  enlargement  the  pressure 
may  cause  erosion  of  the  tracheal  rings  and  collapse  of  the  trachea.  When 
the  enlargement  is  unilateral  the  mobile  trachea  may  escape  pressure  by 
being  pushed  to  the  opposite  side.  Those  tumors  cause  the  most  marked 
pressure  symptoms  which,  developed  from  the  lower  end  of  the  gland  or 
from  ;m  accessory  gland,  lie  between  the  trachea  and  the  sternum. 

The  thick  posterior  border  is  in  contact  with  the  carotid  sheath  and  is 
grooved  by  the  common  carotid  artery.  A  large  goitre  may  press  the 
great  vessels  outward,  it  may  cause  congestion  of  the  face  and  head,  with 
headache,  vertigo,  or  epistaxis  by  pressure  on  the  internal  jugular,  and, 
by  adhering  to  the  latter,  it  may  add  to  the  difficulties  of  excision.  On 
account  of  its  contact  with  the  carotid  the  enlarged  thyroid  may  receive 

pulsation  from  it;  and  if  a  unilateral  thyroid  tumor  is  soft  and  vascular 

the  resemblance  to  aneurysm  is  still  closer,  especially  when  a  thrill  or 

bruit  is  produced,  as  may  be  the  case.     The  pressure  on  the  carotid  and 
internal    jugular   may  disturb   the   cerebral   circulation.      The  thyroid   is 

also  in  contact  with  the  lower  pari  of  the  pharynx  and  with  the  esophagus, 

<  iallv  on  the  left  side,  and  when  enlarged  may  cause  dysphagia. 
The  relation  to  the  recurrent  laryngeal  nerves  is  of  the  utmost    impor- 
tance,as  pressure  on  them  may  lead  to  their  paralysis  and  the  resulting 


154  THE  HEAD  AND  NECK 

alteration  or  loss  of  voice,  and  they  are  also  in  danger  of  being  injured 
in  excision  of  the  thyroid.  The  left  recurrent  nerve  is  more  exposed  to 
pressure,  for  it  lies  more  external  to  and  less  behind  the  trachea.  The 
recurrent  nerves  are  in  danger  of  being  injured  in  the  ligation  of  the 
inferior  thyroid  artery,  being  most  often  found  in  front  of  or  behind 
the  two  branches  of  this  artery,  near  the  point  of  bifurcation.  Hence  the 
artery  is  tied  only  once,  carefully,  and  severed  close  to  its  entrance  on 
the  postero-inferior  aspect  of  the  gland.  The  sympathetic  nerve  is  also  in 
close  relation  to  the  trunk  of  this  artery,  usually  embracing  it,  and  the 
middle  cervical  ganglion  is  in  contact  with  it.  As  the  gland  is  supplied 
by  branches  from  this  ganglion  the  latter  has  been  removed  for  the  cure 
of  exophthalmic  goitre. 

Relatively  to  the  volume  of  the  gland  the  arteries,  superior,  inferior, 
and,  in  the  10  per  cent,  when  present,  the  thyroidea  ima,  are  of  large  size, 
so  that  the  gland  is  one  of  the  most  vascular  of  organs.  There  is  but  little 
arterial  anastomosis  between  the  two  sides  along  the  isthmus,  but  a 
branch  to  the  pyramidal  lobe  from  the  superior  thyroid  may  cross  the 
upper  end  of  the  trachea  and  be  in  the  way  in  tracheotomy.  The  four 
arteries  are  situated  at  the  four  angles  or  poles  of  the  two  lobes  and  run 
some  little  distance  on  the  posterior  surface  before  entering  the  gland. 
The  inferior  thyroid  artery  passes  in  front  of  the  vertebral  and  behind  the 
common  carotid  a  little  below  the  transverse  process  of  the  sixth  cervical 
vertebra.  It  usually  divides  into  two  branches  before  entering  the  gland, 
about  opposite  the  cricoid.  There  is  usually  a  venous  anastomosis  just 
above  and  below  the  isthmus;  the  former  is  between  the  superior  veins, 
the  latter  is  the  starting  point  for  the  inferior  thyroid  veins.  The  superior 
thyroid  veins  cross  the  external  or  common  carotid,  the  inferior  threaten 
the  operator  on  either  side  of  the  wound  in  a  low  tracheotomy,  and  the 
middle  cross  the  common  carotid  about  where  the  omohyoid  crosses  it. 

The  function  of  this  ductless  gland,  which  has  only  an  internal  secretion, 
is  still  imperfectly  understood.  Apparently  it  depends  upon  the  iodine- 
con  taming  albumin  (iodothyrin) ,  which  is  capable  of  replacing  the  thyroid 
secretion.  From  the  effects  of  the  loss  of  the  gland  and  of  the  use  of 
gland  extracts  we  know  that  functionally  the  thyroid  assists  in  metabolism, 
regulating  oxidization  in  the  body,  and  has  a  special  influence  on  (1)  the 
nervous  system,  especially  the  sympathetic  vasomotor  nerves;  (2)  on  the 
skin;  (3)  on  the  osseous  system;  and  (4)  on  the  sexual  functions.  Its 
atrophy,  destruction,  or  complete  removal,  or  the  degenerated  goitrous 
condition  met  with  in  cretins,  is  likely  to  lead  to  cachexia  strumipriva  or 
myxedema,  a  condition  in  which  a  mucinoid  substance  is  deposited  in  the 
subcutaneous  tissues,  especially  in  the  eyelids,  lips,  and  hands.  Hence 
the  entire  gland  should  never  be  removed  for  a  simple  goitre.  One- 
fourth  of  the  gland  is  enough  to  prevent  the  occurrence  of  myxedema. 
An  atrophic  or  degenerated  condition  of  the  gland,  occurring  congenitally 
or  before  puberty,  is  apt  to  be  followed  by  the  interference  with  the 
physical  and  mental  development  and  the  general  nutrition  associated 
with  "cretinism." 

The  most  important  pathological  changes  involving  the  thyroid  consist 


PLATE  X 


FIC.  56 


RIGHT 
PARATHYROIDS 


INFERIOR 
THYROID 
ARTERY 

RECURRENT 
LARYNGEAL 
NERVE 


Parathyroid  Glands.     |  Halsted  and   Evans.) 


THE  NECK  155 

in  an  enlargement  of  a  part  or  the  whole  of  the  gland,  known  as  goitre, 
bronchocele,  or  struma.  This  hypertrophy  may  involve  all  the  elements 
nearly  equally,  or  either  the  parenchyma,  the  fibrous  or  vascular  elements 
more  especially.  Thus  we  may  have  soft  parenchymatous  goitres,  often 
with  one  or  more  cysts  from  enlarged  vesicles,  hard  fibrous  goitres,  and 
again  soft  vascular  goitres.  The  latter  are  associated  with  exophthalmos 
and  tachycardia  in  exophthalmic  goitre.  The  relation  of  the  middle  cervi- 
cal sympathetic  ganglion  and  its  vasomotor  fibers  to  the  inferior  thyroid 
vessels  and  of  other  cervical  sympathetic  fibers  to  the  eye  and  the  heart 
may  perhaps  explain  some  of  the  phenomena  of  this  form.  For  this 
reason  removal  of  the  cervical  sympathetic  has  been  advocated.  Ade- 
nomatous and,  more  rarely,  cancerous  goitres  also  occur.  For  goitres, 
especially  when  they  cause  disturbance  from  pressure,  excision,  enucle- 
ating  excision,  or  enucleation  is  done.  One  side  only  is  usually  operated 
on  in  excision,  but  in  the  latter  two  forms  of  operation,  where  part  of  the 
gland  is  left,  both  sides  may  be  dealt  with. 

In  Kocher's  method  of  excision  a  transverse  "collar"  incision  is  made, 
curved  somewhat  downward,  from  one  sternomastoid  muscle  to  the 
opposite  one.  After  dividing  the  skin,  subcutaneous  tissue,  platysma, 
anterior  jugular  veins,  etc.,  flaps  containing  these  structures  are  turned 
up  and  down.  Then  incising  the  superficial  and  middle  layers  of  the 
cervical  fascia  in  the  median  line  between  the  infrahyoid  muscles,  the 
sternohyoid  and  sternothyroid  muscles  are  retracted  and  may  be  partly, 
or  wholly,  divided  at  their  upper  ends.  The  external  capsule  of  the  gland 
is  then  opened  and  stripped  back  by  blunt  dissection  after  securing  the 
accessory  veins  in  its  outer  surface.  The  tumor  or  gland  lobe  is  then 
delivered  out  of  its  bed  in  a  forward  and  inward  direction  by  blunt  dis- 
section. Then  the  superior  vessels  are  cut  between  two  ligatures  at  the 
upper  pole,  the  inferior  thyroid  artery  cautiously  ligated,  and  its  branches 
cut  where  they  enter  the  gland,  the  inferior  thyroid  veins  cut  between  two 
ligatures,  the  isthmus  divided  after  being  crushed  and  ligated,  and  the 
gland  separated  from  the  trachea.  To  avoid  injury  of  the  recurrent 
laryngeal  nerve  or  removal  of  the  parathyroids  the  postero-internal  part 
of  the  capsule  with  a  little  gland  tissue  should  be  left.  This  constitutes 
the  enucleating  excision. 

The  Parathyroid  Glands.  The  parathyroid  glands  are  small,  reddish- 
brown,  kidney-shaped,  ductless  organs  averaging  ('»  to  7  nun.  (\  in.)  in 
their  long  diameter,  always  enclosed  within  their  own  capsule,  and  gen- 
erally situated  on  or  near  the  posterior  border  of  the  lateral  lobes  of  the 

thyroid  gland.    They  vary  from  one  to  five  in  number,  averaging  about 

th ice,  iii M I  four  is  the  usual  n limber,  with  a  superior  ;ind  an  inferior  gland 
on  either  side.  The  superior  are  generally  on  a  level  with  (he  lower 
border  of  the  cricoid  ca  itilage,  the  inferior  within  1  cm.  of  the  lower  end 
of  the  thyroid,  sometimes  below  it,  and  almost  always  below  the  inferior 
thyroid  artery. 

They  arc  always  supplied  by  a  special  parathyroid  artery,  the  inferior 

always  and  the  superior  usually  from  a  branch  of  the  inferior  thyroid 

or  the  anastomotic  "channel,"  present   in  about  50  per  cent,  of 


156 


THE  HEAD  AND  NECK 


cases,  between  the  inferior  and  superior  thyroid  arteries,  on  the  posterior 
surface  near  the  mesial  border.  At  times  the  inferior  thyroid  arteries 
anastomose  across  the  isthmus,  or  the  parathyroid  artery  may  anastomose 
with  esophageal  arteries. 

The  function  is  very  distinct  from  that  of  the  thyroid.  Removal  of  all 
the  parathyroids  or  the  destruction  of  their  blood  supply  causes  death 
from  acute  tetany.  As  the  loss  of  their  blood  supply  is  the  most  frequent 
cause  of  tetany,  great  care  should  be  observed  in  thyroidectomy  only 
to  tie  the  arteries  that  actually  enter  the  thyroid,  and  hence  also  the  im- 
portance of  the  anastomoses  mentioned  above.     Kocher  advises  against 


Fig.  57 


Fig.  58 


LEFT    BRACHIO- 
CEPHALIC   VEIN 


JO    VERTEBRAL 
COLUMN 


TO    PERICARDIUM 

Sagittal  section  of  the  cervical  fascia  between 
the  hyoid  and  sternum.      (Gerrish,  after  Testut.) 


Sagittal  section  of  the  cervical  fascia  in  the 
clavicular  region.      (Gerrish,  after  Testut.) 


tying  two  main  arteries  at  one  sitting.  The  parathyroids  may  themselves 
be  spared  by  leaving  the  posterior  part  of  the  capsule,  with  perhaps  a 
thin  layer  of  thyroid  tissue.  In  a  considerable  number  of  thyroidectomies 
I  have  never  seen  tetany.  The  posterior  part  of  the  capsule  has  been  left, 
but  no  special  precautions  taken  in  tying  the  arteries,  save  to  avoid  the 
recurrent  nerve.  Injury  to  the  parathyroid  or  its  blood  supply  is  espe- 
cially serious  when  only  one  or  two  are  present  and  on  the  side  of 
operation  only. 

The  Deep  Cervical  Fascia  (Figs.  57,  58,  and  59). — The  deep  cervical 
fascia  is  of  considerable  surgical  importance,  but  its  description  differs 
with  almost  every  writer  on  the  subject,  owing  in  part  to  the  individual 


PLATE  XI 


FIG.  59 


THYROID    GLAND 


ANTERIOR 
/JUGULAR    VEIN 


SUPERFICIAL   LAYER 

FORMING    SHEATH    OF 

STERNO-MASTOID 

RECURRENT 

LARYNGEAL" 

NERVE 

INT    JUGULAR 
VEIN 
COMMON    CARO- 
TID   ARTERY 
VAGUS    NERVE 
SCALENUS   ANTI- 
CUS    MUSCLE 


TRAPEZIUS 
MUSCLE 


MIDDLE    LAYER 
OF    FASCIA 

RECURRENT 
LARYNGEAL 
NERVE 

OMO-HYOID 

MUSCLE 
^ DEEP    LAYER 
^    OF    FASCIA 

PHRENIC 
NERVE 

SYMPATHETIC 
NERVE 


Transverse  Section  of  the  Neck  through  the  Sixth  Cervical 
Vertebra,  to  show  the  layers  of  the  deep  cervical  fascia  and 
their   relations.     Lower  segment  of  the  section.     (Tillaux.) 


THE  NECK  157 

differences  met  with  in  almost  every  case.  In  general,  three  layers  may 
be  described  below  the  hyoid  bone.  The  superficial  layer  splits  to  enclose 
the  sternomastoid  and  trapezius  muscles  in  a  sheath.  This  layer  on  the 
two  sides  unites  anteriorly  in  the  median  line  and  posteriorly  with  the 
ligamentum  nucha?,  thus  forming  a  complete  investment  of  the  neck. 
Below  it  is  attached  to  the  sternum,  clavicle,  the  acromion,  and  the  spinous 
process  of  the  scapula.  In  the  anterior  median  line,  below  the  thyroid 
gland,  this  layer  splits  into  two  divisions  attached  to  the  anterior  and 
posterior  borders  of  the  episternal  notch.  Between  these  two  divisions 
is  a  triangular  space,  continuous  with  the  space  between  the  two  layers 
of  the  sheath  of  the  sternal  head  of  the  sternomastoid,  and  containing 
cellular  and  adipose  tissue  and  one  or  two  small  lymph  nodes  (Paulet). 
Above  the  Jtyoid  bone  it  splits  to  form  a  sheath  for  the  submaxillary  gland 
which  is  attached  to  the  lower  border  of  the  jaw.  Above  this  it  is  con- 
tinuous ^with  the  parotid  and  masseteric  fasciae.  From  the  anterior 
border  of  the  sternomastoid  sheath  a  thickening  passes  forward  to  the 
angle  of  the  jaw  and  is  continued  to  the  styloid  process  as  the  styloman- 
dibular ligament,  which  separates  the  sheath  of  the  submaxillary  from 
that  of  the  parotid  gland.  This  ligament  is  important  in  checking  over- 
action  of  the  external  pterygoid. 

The  middle  layer  is  attached  to  the  hyoid  bone,  covers  the  muscles 
above  it  which  form  the  floor  of  the  submaxillary  triangle,  and  is  attached 
to  the  mylohyoid  ridge.  Below  the  hyoid  it  forms  a  sheath  for  the  sterno- 
hyoid, sternothyroid,  and  omohyoid  muscles.  In  the  median  line,  in  the 
interval  between  these  muscles,  the  fascia  of  the  two  sides  joins  together 
and  with  the  superficial  layer,  forming  a  kind  of  linea  alba  of  the  neck  in 
the  line  of  median  incision.  Laterally  this  layer  is  said  by  some  to  reach 
only  as  far  as  the  limit  of  the  omohyoid,  which  it  ensheathes,  and  by 
others  to  join  the  superficial  layer  near  the  posterior  border  of  the  sterno- 
mastoid. Infer iorly  it  is  continued  down  into  the  mediastinum,  sending 
an  expansion  around  the  left  brachiocephalic  vein,  which  is  continuous 
with  the  fibrous  layer  of  the  pericardium.  More  laterally  it  is  attached 
to  the  posterosuperior  border  of  the  clavicle,  whence  it  sends  an  expan- 
sion around  the  great  veins  behind  it  (subclavian  and  internal  jugular). 
Thence  it  passes  to  the  sheath  of  the  subclavius  muscle,  and  from  the 
latter  is  continuous  with  the  clavipectoral  fascia  (costocoracoid  mem- 
brane). 

Prom  the  deep  surface  of  this  layer  are  given  off  cellular  expansions 
which  surround  in  a  sheath-like  manner  the  trachea,  thyroid  body,  and 
carotid  vessels,  but  do  not  deserve  the  name  of  fasciae,  although  sometimes 
;i  distinct  "pretracheal  layer"  is  described.  The  "suspensory  lig<>- 
meni"  of  the  thyroid  gland,  attaching  it  to  the  cricoid  cartilage,  is  derived 
from  this  expansion.  According  to  Merkel,  the  carotid  sheath  is  made  up 
of  loose  connective  tissue  and  does  not  deserve  the  name  of  sheath.   The 

attachment   Of    this  layer  of   fascia  above   and   the  diaphragm   below   to 

the  pericardium  helps  to  keep  the  latter  so  stretched  as  to  prevent  any 
ire  of  the  lungs  upon  the  heart  (] [ilton  . 
The  deep  or  prevertebral  layer  covers  the  prevertebral  muscles  and  is 


158  THE  HEAD  AND  NECK 

attached  laterally  to  the  cervical  transverse  processes,  where  it  is  con- 
tinuous with  the  sheath  of  the  scalenus  anticus  muscle  and  of  the  brachial 
plexus.  Thence  it  passes  outward  to  join  the  superficial  layer.  Inferiorly 
it  is  continuous  with  the  sheath  of  the  subclavian  and  axillary  vessels. 
According  to  some  it  completes  the  carotid  sheath  posteriorly.  It  lies 
behind  the  esophagus  and  pharynx. 

The  occipital,  superior  carotid,  and  submaxillary  triangles  are  roofed 
over  by  the  superficial  layer;  the  subclavian  and  inferior  carotid  tri- 
angles by  the  superficial  and  middle  layers.  The  layers  as  thus  described 
bound  certain  spaces  and  the  great  practical  importance  of  this  fascia 
consists  in  its  tendency  to  limit  the  growth  of  cervical  tumors  and  the 
course  of  cervical  abscesses.  This  limitation  is  by  no  means  absolute, 
for  abscesses  often  break  through  fascial  planes.  Cold  abscesses  are 
more  likely  to  be  guided  by  fascial  planes  than  those  due  to  acute  inflam- 
mation. 

Between  the  superficial  fascia  and  the  superficial  layer  of  the  deep 
fascia  lie  the  external  jugular  vein,  the  platysma  and  loose  tissue. 
Abscess  here  perforates  externally  and  so  does  one  between  the  super- 
ficial and  middle  layers,  as  the  superficial  layer  is  generally  thin  and 
offers  little  resistance  to  pus.  Hence  there  is  little  tendency  for  abscess 
between  the  superficial  and  middle  layer  to  descend  into  the  mediastinum, 
and  it  is  prevented  from  descending  into  the  axilla  by  the  attachment  of 
the  middle  layer  to  the  clavicle.  Suppuration  is  more  common  here  than 
elsewhere  in  the  neck.  This  compartment  contains  the  anterior  jugular 
veins,  loose  connective  tissue,  and  lymphatic  nodes. 

Abscess  in  the  third  compartment,  that  between  the  middle  and  deep 
layers,  cannot  reach  the  surface  without  perforating  the  two  overlying 
layers,  hence  unless  promptly  relieved  it  is  likely  to  extend  down  into  the 
mediastinum  or  axilla,  with  which  this  space  is  continuous,  depending 
for  its  course  upon  whether  the  abscess  is  situated  mesially  or  laterally. 
Mesially  it  follows  the  loose  tissue  around  the  trachea  and  esophagus, 
as  after  operations  on  the  base  of  the  tongue,  the  larynx,  trachea,  thyroid, 
or  esophagus.  As  this  compartment  also  contains  the  most  important 
structures  of  the  neck,  the  trachea,  esophagus,  thyroid  gland,  carotid 
artery,  and  the  accompanying  vein,  nerves,  and  lymph  nodes,  an  abscess 
may  exert  a  serious  pressure  upon  these  structures.  For  these  two  reasons 
an  early  incision  in  such  deep  abscesses  of  the  neck  is  imperative.  Owing 
to  the  lack  of  it  such  abscesses  have  burst  into  the  trachea  or  esophagus 
and  even  into  the  pleura.  Occasionally  they  have  opened  into  the  great 
vessels,  as  in  a  remarkable  case  reported  by  Mr.  Sarony,  where  a  consider- 
able part  of  the  common  carotid,  a  still  larger  part  of  the  internal  jugular 
vein,  and  a  large  part  of  the  vagus  nerve  were  destroyed  (Treves).  Such 
cases  depend  upon  the  unyielding  character  of  the  cervical  fascia.  The 
communication  between  abscesses  and  large  deep  vessels  have  usually 
taken  place  beneath  the  cervical  fascia  or  the  fascia  lata  (Jacobson). 

In  the  fourth  compartment  an  abscess  is  known  as  prevertebral  or  retro- 
pharyngeal, if  above  the  lower  limit  of  the  pharynx.  The  latter  form  may 
be  opened  through  the  mouth  or  from  the  side  of  the  neck,  and  if  unrelieved 


THE  NECK 


159 


may  gravitate  down  into  the  mediastinum.  Laterally  these  deep  abscesses 
may  follow  the  brachial  plexus  to  the  posterior  triangle  or  even  to  the 
axilla.  The  retropharyngeal  abscesses  arising  from  infected  lymph 
nodes  are  in  front  of  the  prevertebral  fascia,  behind  the  pharynx.  In 
general,  then,  superficial  abscesses,  or  those  external  to  the  middle  layer, 
are  comparatively  safe,  showing  a  tendency  to  perforate  and  open  exter- 
nally; deep  abscesses,  or  those  beneath  the  middle  layer,  are  dangerous 
from  pressure  or  the  liability  to  extend  into  the  mediastinum,  and  should 
be  relieved  by  incision  as  promptly  as  possible. 

As  the  cervical  fascia  gives  a  sheath  to  the  large  veins  that  perforate 
it  and  are  in  contact  with  it  and  attaches  them  closely  to  the  adjacent 


Fig.  60 


GLANDS    OF 

EXTERNAL  JUGULAR 

CHAIN 


SUBMAXILLARY 


GLAND  OF 
INTERNAL  JUGULAR 
CHAIN 


The  lymphatics  of  the  neck.      (Kiittner.) 


bones  and  muscles,  they  are  thereby  held  patent  and  ready  for  the  free 
How  of  blood  from  the  head  and  neck,  and  at  the  same  time  they  are 
more  liable  to  gape  when  wounded,  so  as  to  admit  air.  I  lenee  they  should 
always  be  ligated  before  division.  According  to  some  the  Cervical  fascia, 
-on  of  its  firmness  and  LtS  attachment  to  bones  above  anil  below, 
supports  the  soft  pints  of  the  neck,  especially  the  veins,  ami  helps  (hem 

to  reriat  atmospheric  pressure  in  inspiration,  as  first  pointed  oul  by  Allan 
Burns. 

The  Lymphatic  Nodes  (Fig.  GO). — The  lymphatic  nodea  of  the  neck 

receive   the  hjiii phat ics  of  the   heat/  and  face,  and   are   Liable  to  become 
enlarged  in  the  COUTM  of  the  various  septic,  tuberculous,  syphilitic,  and 

cancerous  affections  of  the  parts  from  which  their  lymphatics  come. 


160  THE  HEAD  AND  NECK 

Among  enlarged  lymph  nodes  of  the  neck  lymphadenoma  of  tuberculous 
origin  is  a  very  common  condition,  and  forms  the  majority  of  tumors 
of  the  neck,  the  source  of  infection  being  usually  the  upper  air  passages 
(nose,  nasopharynx,  pharynx,  and  tonsils).  The  breaking  down  of 
enlarged  cervical  nodes  is  a  common  cause  of  abscess  of  the  neck.  It 
follows  that  it  is  important  to  have  a  clear  idea  of  the  sources  from  which 
the  several  groups  of  nodes  are  supplied  both  to  aid  in  the  diagnosis  of 
the  primary  lesion  and  in  order  to  know  where  to  look  for  lymphatic 
involvement  in  any  given  lesion. 

The  suboccipital  nodes,  just  below  the  posterior  attachment  of  the 
occipitofron talis  and  just  lateral  to  the  trapezius,  receive  lymph  from  the 
back  part  of  the  scalp,  and  are  frequently  enlarged  in  secondary  syphilitic 
eruptions  of  this  part.  The  mastoid  nodes,  just  over  the  insertion  of  the 
sternomastoid,  and  the  parotid  nodes,  on  and  in  the  parotid  gland,  receive 
the  lymph  from  the  middle  and  anterior  part  of  the  scalp  respectively. 
The  parotid  nodes  also  receive  lymphatics  from  the  eyelids,  the  root  of 
the  nose,  the  external  surface  of  the  auricle,  the  external  auditory  canal, 
and  the  tympanum.  For  the  postpharyngeal  nodes  see  p.  127.  The  five  or 
six  submaxillary  nodes,  under  the  sheath  of  the  submaxillary  gland  in  the 
digastric  triangle,  form  a  chain  along  the  lower  border  of  the  jaw.  Their 
tributaries  come  from  the  upper  lip  and  lateral  part  of  the  lower  lip, 
the  forepart  of  the  lateral  border  of  the  tongue,  the  nose,  cheek,  and  gums. 
The  one  to  four  submental  nodes,  on  the  mylohyoid  and  between  the 
anterior  bellies  of  the  digastric,  receive  lymphatics  from  the  middle  of 
the  lower  lip  and  chin,  the  tip  of  the  tongue,  and  the  floor  of  the  mouth. 

Facial  Nodes. — These  consist  of  three  groups  of  small  glands  along 
the  course  of  the  facial  vessels.  They  are  traversed  by  the  afferent  ves- 
sels of  the  submaxillary  nodes.  They  are  found  on  the  surface  of  the 
jaw,  in  front  of  the  masseter,  on  the  outer  surface  of  the  buccinator,  etc. 

The  subparotid  nodes  lie  between  the  parotid  and  the  pharynx  in 
contact  with  the  great  vessels.  They  receive  afferents  from  the  nasal 
fossae,  nasopharynx,  and  Eustachian  tubes,  and  may  be  the  starting  point 
of  a  lateral  pharyngeal  abscess. 

The  above  nodes  empty  into  the  deep  cervical  nodes  which  accom- 
pany the  internal  jugular  vein  to  its  lower  end.  They  are  arranged  in 
two  sets,  an  external  or  posterior  chain  near  the  posterior  border  of  the 
sternomastoid  and  an  internal  chain  on  or  just  external  to  the  internal 
jugular.  The  former  comprises  smaller  and  fewer  nodes  whose  afferents 
come  from  the  posterior  part  of  the  head  and  neck.  All  the  nodes  are 
beneath  the  sternomastoid  and  the  deep  layer  of  its  sheath.  They  are 
largest  and  most  numerous  above  and  may  lie  entirely  above  the  point 
where  the  omohyoid  crosses  the  vein.  Just  above  this  point  there  is 
always  a  fair-sized  node,  there  are  also  one  or  two  large  ones  just  beneath 
the  posterior  belly  of  the  digastric,  which  are  the  chief  terminus  of  the  lym- 
phatics of  the  tongue.  At  the  base  of  the  neck  the  efferents  communicate 
with  those  of  the  subclavian  and  axillary  nodes,  to  form  a  common  trunk. 
In  addition  to  the  deep  cervical  chains  three  or  four  accessory  chains  may 
be  distinguished: 


THE  NECK  161 

1.  The  external  jugular  chain  comprises  two  to  five  nodes  along  the 
upper  part  of  the  external  jugular  vein,  on  the  outer  surface  of  the  sterno- 
mastoid,  with  sometimes  one  or  two  nodes  below. 

2.  The  superficial  anterior  cervical  chain  along  the  anterior  jugular 
vein  comprises  two  or  three  inconstant  nodes. 

3.  The  anterior  deep  cervical  chain  are  composed  of  two  or  three  groups 
of  small  inconstant  nodes  in  front  of  the  larynx,  thyroid  gland,  and  trachea. 

4.  The  recurrent  chain  consists  of  a  few  small  nodes  along  the  recurrent 
laryngeal  nerve. 

As  the  nodes  in  the  subclavian  triangle  communicate  directly  with  the 
axillary  nodes,  they  may  become  involved  in  carcinoma  of  the  breast, 
but  as  they  receive  no  vessels  from  the  mediastinal  glands  their  involve- 
ment following  gastric  carcinoma  can  only  be  explained  by  a  retrograde 
thrombosis  of  their  efferent  vessels.    Such  involvement  is  very  unusual. 

In  most  cases  where  the  nodes  are  exposed  by  operation  many  more 
are  involved  than  expected,  and  a  chain  of  glands,  gradually  decreasing 
in  size,  leads  downward  from  the  position  of  the  visible  tumor.  Therefore, 
in  removing  cervical  lymphadenoma  the  operation  often  proves  more 
extensive  and  formidable  than  expected.  They  may  be  considerably 
enlarged  without  detection  by  palpation,  and  we  often  feel  them  without 
suspecting  their  real  size  or  numbers.  In  removing  them  their  relation  to 
the  internal  jugular  vein  is  of  great  importance,  as  they  may  be  adherent 
to  it  and  difficult  to  separate  from  it,  especially  when  involved  secondarily 
to  cancer.  In  such  cases  the  vein  and  surrounding  lymph-bearing  tissue 
should  be  removed  without  hesitation.  With  the  exception  of  a  few, 
like  the  external  jugular  chain,  the  cervical  lymph  nodes  lie  beneath  the 
deep  fascia.  They  may  also  be  enlarged  in  the  rare  cases  of  lymphosar- 
coma and  in  the  peculiar  affection  known  as  Hodgkin's  disease.  Although 
in  most  cases  of  involvement  of  the  lymph  nodes  the  infection  comes  from 
the  same  side  of  the  body  as  the  enlargement,  yet  in  exceptional  cases  it 
comes  from  the  opposite  side.  Thus  exceptionally  when  one  side  of  the 
tongue  is  the  seat  of  epithelioma  the  opposite  submaxillary  nodes  arc 
involved. 

Embryology. — Embryologically  the  neck  is  formed  by  the  coalescence 
of  five  visceral  arches  separated  by  four  furrows  or  clefts.  These  furrows, 
seen  on  the  surface,  correspond  to  a  like  number  of  inner  clefts  or  pharyn- 
geal pouches  on  the  walls  of  the  pharynx,  separated  from  the  outer  clefts 
by  a  thin  occluding  membrane,  comiposed  of  a  layer  of  entoderm  and  one  of 
ectoderm.  Of  these  arches  and  clefts  the  first  arch  becomes  differentiated 
into  ;i  maxillary  and  a  mandibular  process,  which  form  the  upper  and 
lower  jaws,  the  incus  and  the  malleus;  the  second  arch  contributes  the 
itapes,  the  styloid  process,  the  stylohyoid  liga incut,  and  the  lesser  eoniu 
of  the  hvoid  hone;  the  third  forms  the  body  and  great  eoniu  of  the  hvoid  ; 
the  fourth  and  fifth  arches,  the  second  and  third  brnnehial  in  man,  form 
no  special   Structures,  but  soon   blend  with   surrounding  structures  and 

lose  their  identity.    The  first  outer  cleft  forms  the  external  ear,  the  corre- 
sponding iniMr  cleft  the  middle  ear  and  Kuslarhian  tube,  and  the  closing 
membrane   between   them    forms   the    ineinbrana    lyinpani.      The   second 
I  I 


162  THE  HEAD  AND  NECK 

pharyngeal  pouch  is  probably  represented  by  the  fossa  of  Rosenmiiller. 
The  fourth  inner  cleft  contributes  to  the  formation  of  the  thyroid  gland, 
and  the  tissues  of  the  ventral  ends  of  the  second  branchial  arches  take 
part  in  forming  the  posterior  third  of  the  tongue  and  most  of  the  thyroid 
gland,  through  the  thyroglossal  duct. 

If  the  lower  or  branchial  arches  do  not  fuse  together,  as  they  normally 
should  in  the  second  month  of  fetal  life,  the  corresponding  cleft  remains 
partly  open  as  a  so-called  branchial  fistula.  These  may  be  complete  or 
incomplete.  In  the  case  of  complete  fistula0,  the  closing  membrane  gives 
way  and  there  is  a  narrow  canal  lined  by  mucous  membrane,  leading  from 
without  backward,  inward,  and  upward  for  3.5  to  6.5  cm.  (1^  to  2\  in.). 
The  internal  opening  of  such  a  fistula  is  usually  near  Rosenmuller's  fossa, 
the  tonsillar  sinus,  or  the  pyriform  sinus  of  the  larynx.  The  external 
opening  varies  in  position  according  to  the  cleft  which  remains  open, 
being  most  often  near  the  sternoclavicular  joint,  in  the  region  of  the 
fourth  cleft,  or  at  the  anterior  or  posterior  border  of  the  sternomastoid 
near  the  level  of  the  larynx,  in  the  second  or  third  cleft.  Incomplete 
fistula?  open  either  externally  or  internally  in  the  same  position  as  one 
end  of  a  complete  fistula.  Near  the  external  opening  of  a  fistula,  or  in 
spots  where  they  commonly  open,  a  protruding  fold  of  skin  may  be  found, 
and  above  it  a  cartilaginous  mass  is  sometimes  to  be  felt.  As  the  external, 
ear  is  formed  by  the  fusion  of  six  similar  nodules  at  the  outer  end  of  the 
first  visceral  cleft,  the  more  prominent  of  these  are  called  cervical  auricles. 
Median  fistulas  of  the  neck,  or  tracheal  fistulse,  are  rare,  and,  if  incom- 
plete and  internal,  may  give  rise  to  tumors  filled  with  air. 

From  obstruction  of  the  external  or  internal  opening  of  a  fistula  or 
from  a  portion  of  the  wall  of  the  cleft  shut  in  by  the  closure  of  the  arches, 
dermoid  and  branchiogenic  cysts  may  be  formed.  Such  shut-in  portions 
of  epithelial  tissue  may  be  the  nucleus  of  the  rare  primary  carcinomata 
of  the  neck. 


CHAPTER    II. 

THE  UPPER  EXTREMITY. 

The  upper  extremity,  the  organ  of  prehension  and  touch,  is  notable 
for  its  mobility,  which  is  due  to  the  freedom  of  movement  of  its  joints 
and  its  many  muscles.  Its  only  bony  connection  with  the  skeleton  of 
the  trunk  is  through  the  clavicle. 

In  the  upright  position  the  upper  extremity  reaches  to  the  middle 
of  the  thigh,  the  right  being  stronger  and  ^  to  1  cm.  (-J-  to  f  in.)  longer, 
as  a  rule.  The  greater  development  of  the  right  upper  extremity  depends, 
according  to  Hyrtl,  on  the  arrangement  of  the  blood  supply  which 
on  the  right  side,  is  more  abundant  and  comes  more  directly  from  the 
heart.  The  anomalous  origin  of  the  right  subclavian  as  the  last  branch 
of  the  aortic  arch  is  associated,  according  to  the  same  author,  with 
left-handedness  and  the  greater  development  of  that  side. 

THE  REGION  OF  THE  SHOULDER. 

This  comprises  the  upper  part  of  the  extremity  and  reaches  down  to 
the  insertion  of  the  pectoralis  major  and  latissimus  dorsi  muscles. 

Surface  Landmarks  and  Markings. — The  clavicle,  acromion  process, 
spine,  vertebral  border,  and  angle  of  the  scapula  can  be  readily  felt  svb- 
cutaneously.  The  clavicle  is  not  quite  horizontal,  but  in  robust  muscular 
persons  and  in  the  emphysematous  it  inclines  slightly  upward  at  its 
outer  end  in  the  erect  position,  and  even  more  so  in  the  reclining  position 
when  the  weight  of  the  arm  no  longer  pulls  it  down.  On  the  other  hand, 
in  narrow-chested,  feeble,  and  consumptive  persons  the  outer  ends  of 
the  clavicles  incline  downward,  causing  the  long  necks  and  narrow 
sloping  shoulders  seen  in  such  persons.  The  upper  surface  is  only 
covered  by  skin  and  platysma  and  the  anterior  and  posterior  surfaces  are 
also  more  or  less  readily  palpable.    The  deltoid  tubercle  of  this  bone  may 

be  fell  if  large,  and  may  even  be  mistaken  for  an  exostosis.    The  curves  of 

the  bone  are  :i|>f  to  be  exaggerated  in  muscular  persons.  The  sternal  cud 
is  large  and  prominent,  especially  in  muscular  subjects,  and  the  outer  or 
acromial  end  is  often  enlarged  and  commonly  projects  above  the  level  <»t' 
the  acromion,  so  thai  it  should  noi  be  mistaken  lor  a  dislocation  al  the 
acromioclavicular  joint.  The  hitter  joint  is  in  the  sagittal  plane,  passing 
up  the  middle  of  the  arm  anteriorly.  The  easiest  w;iy  of  determining 
shortening  of  the  clavicle,  in  fracture  or  dislocation  of  thai  bone,  Is  by 
measurement  from  the  outer  edge  of  the  acromion  to  the  suprasternal 
notch.     The  angular  prominence  which  can  be  fell  externally  at  the 


164  THE  UPPER  EXTREMITY 

junction  of  the  acromion  and  the  spine  of  the  scapula  is  the  best  point  from 
which  to  measure  the  arm  down  to  the  external  condyle.  The  latter  point, 
the  tip  of  the  acromion,  and  the  radial  styloid  process  are  all  in  the  same 
line  when  the  arm  hangs  at  the  side  and  the  palm  looks  forward. 

When  the  arm  hangs  at  the  side  the  upper  angle  of  the  scapula  corre- 
sponds to  the  upper  border  of  the  second  rib,  the  lower  angle  to  the 
seventh  intercostal  space.  Hence  the  latter  is  a  guide  in  selecting  a  space 
for  aspiration  or  drainage  of  the  chest  in  empyema,  etc.  The  vertebral 
end  of  the  spine  of  the  scapula  is  opposite  to  the  third  thoracic  spine, 
and  to  the  fissure  between  the  upper  and  lower  lobes  of  the  lung. 

The  vertebral  border  of  the  scapula  may  be  made  prominent  for  exami- 
nation by  carrying  the  hand  as  far  as  possible  over  the  opposite  shoulder, 
the  axillary  border  and  inferior  angle  by  placing  the  forearm  behind  the 
back.  The  vertebral  borders  are  parallel  with  the  line  of  the  thoracic 
spines  when  the  arms  hang  at  the  side.  When  the  arms  are  crossed  on 
the  front  of  the  chest  these  borders  are  widely  separated,  hence  this 
position  is  employed  for  auscultation  and  percussion. 

The  prominence  of  the  shoulder  is  due  to  the  acromion  process,  but  the 
roundness  just  below  this  depends  upon  the  prominent  great  tuberosity 
of  the  humerus  covered  by  the  deltoid  muscle.  Hence  this  roundness 
gives  way  to  a  flattening  when  the  underlying  bony  bolster  is  removed, 
as  in  a  dislocation  of  the  shoulder,  or  is  diminished  in  bulk,  as  in  an 
impacted  fracture  of  the  anatomical  neck.  The  head  of  the  humerus  can 
be  felt  high  up  in  the  axilla,  especially  when  the  arm  is  abducted,  which 
brings  the  head  in  contact  with  the  lower  part  of  the  joint  capsule.  The 
lower  margin  of  the  glenoid  cavity  can  also  be  felt  high  up  in  the  axilla 
below  the  humeral  head.  The  head  and  internal  condyle  of  the  humerus 
and  the  styloid  process  of  the  ulna  are  in  the  same  line.  This  relation  of 
the  head  and  internal  condyle,  being  constant  in  all  positions  of  the  arm, 
is  of  value  in  the  diagnosis  of  injuries  about  the  shoulder  and  in  reducing 
dislocations,  by  enabling  us  to  determine  the  position  in  which  the  head 
should  be  from  the  position  of  the  internal  condyle.  In  thin  subjects 
the  two  tuberosities  of  the  humerus  and  the  bicipital  groove  between  them 
can  be  felt  beneath  the  deltoid,  especially  on  rotating  the  humerus.  The 
bicipital  groove  looks  directly  forward  when  the  arm  hangs  at  the  side 
with  the  palm  of  the  hand  looking  forward. 

The  groove  between  the  deltoid  and  pectoralis  major,  distinguishable 
in  most  cases,  contains  the  cephalic  vein  and,  more  deeply,  the  humeral 
branch  of  the  acromiothoracic  artery.  The  upper  end  of  this  groove 
widens  out  into  a  triangular  infraclavicular  fossa,  the  base  of  the  triangle 
being  formed  by  the  clavicle.  On  deep  pressure  here  the  coracoid  process 
can  be  felt  just  beneath  the  margin  of  the  deltoid  and  a  little  below  the 
clavicle.  The  depression  of  the  infraclavicular  fossa  is  obliterated  in 
subcoracoid  dislocations  of  the  humerus,  in  some  fractures  of  the  clavicle 
with  displacement,  in  some  axillary  tumors,  in  lymphatic  enlargements 
and  in  inflammations  along  the  upper  part  of  the  axillary  artery.  It  is 
replaced  by  a  prominence  in  intracoracoid  dislocations  of  the  humerus. 
If  the  muscles  are  relaxed  we  may  detect  the  pulsation  of  the  axillary 


THE  ANTERIOR  REGION  OF   THE  SHOULDER  K;;, 

artery  by  pressure  in  the  infraclavicular  fossa  below  the  middle  of  the 
clavicle  just  to  the  inner  side  of  the  coracoid  process,  and  we  may  also 
compress  the  artery  against  the  second  rib.  By  a  vertical  incision  through 
the  centre  of  the  eoraeo-acromial  ligament  the  shoulder  joint  is  opened  and 
the  biceps  tendon  is  encountered.  Hence  in  resection  of  the  shoulder 
joint  the  coracoid  process  is  a  landmark  for  the  incision. 

The  anterior  border  of  the  axilla  is  formed  by  the  lower  mart/in  of 
the  great  pectoral  muscle  which  passes  from  the  sixth  costal  cartilage  to 
the  outer  bicipital  ridge  and  nearly  follows  the  line  of  the  fifth  rib.  The 
anterior  and  posterior  axillary  borders  are  well-marked,  especially  when 
the  arm  is  abducted  to  an  angle  of  about  45  degrees  and  the  muscles 
forming  these  borders  are  contracted,  in  which  position  the  depression 
of  the  axilla  is  deepest.  As  the  arm  is  raised  to  and  above  the  horizontal 
line,  the  axillary  depression  becomes  shallower  by  reason  of  the  projection 
into  it  of  the  humeral  head,  the  approximation  of  the  anterior  and  pos- 
terior axillary  folds,  and  the  projection  of  the  coracobrachialis  muscle 
along  the  humeral  side  of  the  axilla.  When  the  arm  is  brought  nearlv 
to  the  side  the  thoracic  wall  bounding  the  axilla  internally  can  be  explored 
as  high  up  as  the  third  rib.  The  axillary  lymph  nodes  on  this  or  on  the 
otiter  side  cannot  be  felt  unless  they  are  enlarged. 

Topography  of  Some  of  the  Deeper  Parts. — When  the  arm  is 
abducted  the  course  of  the  axillary  artery  is  represented  by  a  line  from 
the  centre  of  the  clavicle  to  the  groove  along  the  inner  border  of  the 
coracobrachialis  muscle.  The  latter  muscle  comes  well  into  view  when 
the  humerus  is  rotated  a  little  outward. 

The  position  of  the  pectoral  is  minor  muscle  is  outlined  by  two  lines 
converging  from  the  upper  border  of  the  third  and  the  lower  border  of 
the  fifth  rib.  just  external  to  their  cartilages,  to  the  coracoid  process. 
The  position  of  the  acromiothoracic  artery  is  indicated  by  the  point  where 
the  upper  line  crosses  the  course  of  the  axillary  artery  and  the  long 
thoracic  artery  runs  in  the  lower  line.  When  the  arm  hangs  at  the  side 
the  circumflex  nerve  and  posterior  circumflex  artery  wind  around  the 
humerus  under  the  deltoid  about  a  finger's  breadth  above  the  centre  of 
the  vertical  axis  of  this  muscle.  At  the  latter  point  the  dorsalis  scapula 
artery  crosses  the  axillary  bonier  of  the  scapula   (Tre 

For  convenience  of  study  we  may  divide  the  shoulder  into  four  regions: 
(1)  the  anterior  or  clavicular  region;  (2)  the  posterior  or  scapular 
region;  •">  <  the  outer  or  deltoid  region  (including  the  shoulder  joint); 
and    t    the  axilla. 

The  Anterior  Region  of  the  Shoulder. 

This  i-  also  called  the  clavicular  region  because  the  clavicle  form-  it- 
bony  framework.  The  skin  over  this  region  is  loosely  attached  ami.  hence, 
movable,  a  fact  which  explains  why  it  usually  escapes  being 
wounded  in  contusions  and  partly  accounts  for  the  rare  occurrence  of 
compounding  in  fracture-  of  the  clavicle.  The  supraclavicular  nerves, 
the  cutaneous  nerves  of  this  region,  in  their  passage  in  front  of  the  middle 


166  THE  UPPER  EXTREMITY 

third  of  the  clavicle  are  liable  to  contusion,  and  such  an  injury  explains 
the  occasional  severe  pain  after  blows  on  the  clavicle.  According  to 
Tillaux,  the  severe  pain  which  occasionally  persists  after  fractures  of  the 
clavicle  is  due  to  the  involvement  of  these  nerves  in  the  callus. 

Fracture  of  the  clavicle  is  one  of  the  commonest  forms  of  fracture, 
a  fact  due  to  its  superficial  position,  its  slender  form,  and  the  circum- 
stance that  it  receives  a  large  share  of  almost  all  shocks  which  involve 
the  upper  extremity.  Such  fractures  are  more  often  due  to  indirect  than 
to  direct  violence.  The  great  majority  of  the  indirect  fractures  are  at 
the  outer  end  of  the  middle  third  (i.  e.,  the  middle  5  cm.  (2  in.)  of  the  bone, 
for  the  reason  that  this  is  the  most  slender  and  most  sharply  curved  part 
and  also  the  meeting  point  of  the  two  curves  and  of  the  more  fixed  outer 
third  with  the  more  movable  inner  two-thirds.  In  this  connection  it 
may  be  noted  that  the  clavicle  breaks  in  such  cases  by  the  exaggeration 
of  its  normal  curves. 

The  direction  of  the  fracture  is  accordingly  usually  obliquely  inward, 
downward,  and  backward.  As  to  the  displacement  that  occurs,  it  should 
be  borne  in  mind  that  as  the  outer  third  of  the  clavicle  is  firmly  attached 
to  the  scapula,  its  displacement,  after  fracture  internal  to  it,  will  be  deter- 
mined by  the  change  in  position  of  the  scapula;  also  that  the  clavicle 
serves  as  a  kind  of  outrigger  to  hold  the  shoulder  and  upper  extremity 
away  from  the  thorax.  When  this  support  is  broken  the  shoulder  with 
the  outer  fragment  is  naturally  displaced  inward  and  sinks  downward 
by  its  own  weight.  The  inward  displacement  also  causes  the  shoulder  to 
swing  forward  so  that  the  common  displacement  of  the  inner  end  of  the 
outer  fragment  is  downward,  inward,  and  forward.  The  outer  end  of 
the  outer  fragment  is  also  rotated  forward.  This  outrigger  action  of  the 
clavicle  may  be  illustrated  by  a  bar  supporting  a  sign  from  a  building, 
the  outer  end  of  the  bar  being  also  supported  by  a  chain  from  a  point 
higher  up  on  the  wall,  the  chain  representing  the  trapezius,  etc.  If  the 
bar  breaks  the  outer  end  with  the  sign  falls  downward  and  inward. 
But  this  is  not  the  only  and  perhaps  not  the  most  important  cause  of 
the  displacement,  the  other  causes  being  the  continuance  of  the  force 
producing  the  fracture,  the  direction  of  the  fracture,  and  the  action  of  the 
muscles.  Thus  in  transverse  fractures  there  may  be  no  such  displace- 
ment, but  instead  of  it  an  angular  one  with  the  apex  upward  and  back- 
ward, due  to  the  sinking  of  the  shoulder  downward  and  forward,  or  there 
may  be  no  displacement  at  all,  especially  in  green-stick  fractures.  Again, 
if  the  oblique  direction  is  much  inclined  inward  and  backward,  the  inner 
end  of  the  outer  fragment  may  be  forced  behind  or  simply  below  the  inner 
fragment  and  not  in  front  of  it.  Among  the  muscles  the  pectorals  and 
latissimus  dor  si  pull  the  outer  fragment  inward  and  downward.  The 
outer  end  of  the  outer  fragment  is  rotated  forward  by  the  pectorals  and 
the  serratus  magnus.  The  inner  fragment,  if  displaced  at  all,  is  pushed 
up  by  the  outer  fragment  beneath  it,  rather  than  pulled  up  by  the  sterno- 
mastoid,  for  the  action  of  the  latter  is  resisted  by  the  rhomboid  liga- 
ment, the  upper  and  inner  fibers  of  the  pectoralis  major,  and  by  the 
subclavius. 


THE  ANTERIOR  REGION  OF  THE  SHOULDER  107 

( )\ving  to  the  inward  displacement  of  the  outer  fragment  causing  the 
fragments  to  overlap,  there  is  necessarily  a  considerable  shortening 
which  may  nearly  equal,  in  extreme  cases,  one-third  the  length  of  the 
bone,  or  5  cm.  (2  in.).  As  this  shortening  is  difficult  to  remedy  com- 
pletely, it  follows  that  some  shortening  remains  permanently  after  fracture 
of  the  clavicle  more  often  than  after  any  other  fracture  save  that  of  the 
femur.  This  shortening  causes  some  narrowing  and  rounding  of  the 
affected  shoulder. 

It  follows  from  the  nature  of  the  displacement  that  reduction  is  to  be 
obtained  and  maintained  by  carrying  the  shoulder  upward,  outward,  and 
backward.  Upward  pressure  on  the  elbow  carries  the  shoulder  upward, 
and,  with  a  pad  in  the  axilla  as  a  fulcrum  and  the  arm  as  a  lever,  inward 
pressure  at  the  elbow  forces  the  shoulder  outward.  But  if  the  pad  is 
large  enough  to  be  of  much  use,  it  may  be  dangerous  from  its  pressure 
on  the  vessels  and  nerves,  and  if  it  is  small  enough  to  avoid  these  dangers, 
it  is  useless.  Some  shortening  and  deformity  usually  persists,  and' any 
forward  displacement  of  the  outer  fragment  may  be  particularly  hard  to 
keep  reduced  unless  the  patient  is  willing  to  lie  perfectly  flat  on  the  back 
with  the  head  slightly  elevated  for  three  weeks  or  so.  In  this  recumbent 
position  the  weight  of  the  arm  no  longer  drags  the  shoulder  downward, 
and  the  weight  of  the  shoulder  and  the  pressure  of  the  body  on  the  verte- 
bral half  of  the  scapula,  forcing  its  outer  border  outward  and  backward, 
pull  the  outer  fragment  outward  and  backward,  and  correct  its  forward 
rotation  and  displacement  better  than  any  form  of  bandage.  The  mobility 
of  the  clavicle  and  the  number  of  strong  muscles  attached  to  it  explain 
the  difficulty  of  applying  a  satisfactory  fixed  dressing  and  the  tendency 
of  the  callus  to  become  excessive.  In  fracture  of  the  outer  third,  the  next 
most  common  variety,  which  is  more  often  transverse  than  oblique,  there 
may  be  no  displacement  or  an  angular  one,  directed  backward,  due  to 
the  forward  and  inward  turning  of  the  outer  fragment. 

The  clavicle  may  be  broken  by  muscular  violence,  probably  by  the 
clavicular  fibers  of  the  pectoralis  major  and  deltoid.  These  tend  to  draw 
the  clavicle  downward  and  forward,  in  which  position  the  outer  fragment 
is  displaced  in  such  cases.  These  fractures  are  most  often  in  the  middle 
third.  Violent  movements  of  the  limb  forward  and  inward  or  upward 
appear  to  be  the  commonest  cause.  Occasionally  the  fracture  is  due 
to  ;i  sudden  depression  of  the  arm,  by  which  the  clavicle  is  bent  over  the 
first  rib.  Fractures  by  direct  violence  are  most  apt  to  be  transverse 
and  may  occur  at  any  point,  but  most  frequently  at  the  middle  or  outer 

third. 

Green-stick  fracture,  or  fracture  without  rupture  of  the  periosteum, 
and  hence  without  much  displacement,  occurs  more  often  in  the  clavicle 
than  in  any  other  bone  This  is  partly  due  to  the  fad  that  such  frac- 
tures occur  in  childhood,  and  more  than  half  the  fractures  of  the  clavicle 
are  said  to  occur  before  the  age  of  five.  According  fo  Krdnlein  fracture 
of  the  clavicle  in  children  takes  the  place  of  dislocation  <>f  the  shoulder  bv 
direct  violence  in  Inter  life.  The  periosteum  ;it  this  age  is  also  very  thick 
and  loosely  attached.    Notwithstanding  the  absence  of  marked  deformity 


168  THE  UPPER  EXTREMITY 

and  of  much  disability,  and  the  failure  of  diagnosis  that  may  result, 
the  callus  is  often  excessive,  owing  to  the  stripping  up  of  the  active 
periosteum. 

The  firmness  of  the  'periosteum,  the  common  situation  of  the  fracture, 
external  to  the  middle  of  the  bone  and  to  the  region  of  danger,  but 
especially  the  presence  beneath  the  clavicle  of  the  subclavius  muscle, 
enveloped  in  a  dense  fascia,  are  largely  accountable  for  the  rare  occurrence 
of  the  complications  of  fractures  of  the  clavicle,  which  consist  of  injuries 
to  the  vessels,  nerves,  and  lung.  Although  the  vessels  and  nerves  lie 
beneath  the  clavicle  in  the  angular  interval  between  it  and  the  first  rib 
in  the  following  order  from  within  out,  subclavian  vein,  artery,  and 
brachial  plexus,  injury  to  the  artery  is  not  recorded,  unless  of  such  a 
nature  as  to  produce  subsequent  aneurysm,  and  only  a  few  cases  of  injury 
to  the  vein  and  brachial  plexus  are  on  record  in  fractures  of  the  clavicle. 
The  vein  from  its  position,  as  the  most  internal  of  these  structures  in 
the  acute  angle  between  the  clavicle  and  the  first  rib,  and  from  its  slighter 
resistance  is  likely  to  be  the  first  to  be  compressed.  Injury  to  the  internal 
jugular  vein,  lying  behind  the  clavicle,  has  also  been  recorded.  Injury 
to  the  lung  by  a  fragment  of  the  clavicle,  as  evidenced  by  emphysema, 
has  been  observed  in  a  few  cases,  and  in  other  cases  the  emphysema 
was  apparently  due  to  a  wound  of  the  soft  parts. 

The  subclavius  muscle,  interposed  as  a  pad  between  the  vessels  and 
nerves  and  the  clavicle,  is  of  great  service  in  resection  of  the  latter,  render- 
ing the  operation  easy  in  the  outer  two-thirds,  while  behind  the  sternal 
third  are  the  innominate  or  left  carotid  artery,  the  brachiocephalic  and 
internal  jugular  veins,  the  vagus,  recurrent,  and  phrenic  nerves,  the  thor- 
acic duct  and  the  trachea.  A  little  more  externally  the  external  jugular 
vein,  the  suprascapular  vessels  and  the  apex  of  the  lung  lie  behind  the 
clavicle.  In  case  of  enlargement  of  the  clavicle  from  tumor  (sarcoma), 
the  resection  of  its  inner  third  may  be  a  matter  of  considerable  difficulty, 
though  in  case  of  necrosis  with  thickening  of  the  periosteum  the  operation 
is  rendered  much  easier  and  safer,  if  it  can  be  done  subperiosteal^ .  The 
restoration  of  the  clavicle  after  subperiosteal  resection  is  sometimes  very 
complete,  but  even  when  no  new  bone  forms  the  removal  of  the  entire 
clavicle  is  followed  by  far  less  alteration  in  position  and  impairment  of 
motion  of  the  shoulder  than  would  be  expected  from  its  function  as  a 
support  and  outrigger  for  the  shoulder.  The  same  is  true  in  the  occasional 
congenital  absence  of  the  clavicles  or  of  their  acromial  ends  and  in  the  arrest 
of  their  development  from  epiphyseal  separation.  So  striking  is  this  in 
some  cases  as  to  lead  one  to  question  whether  the  displacement  in  frac- 
ture of  the  clavicle  is  not  mostly  due  to  the  other  factors,  i.  e.,  continuation 
of  the  force  producing  the  fracture,  muscular  action,  and  the  direction 
of  the  fracture. 

Avulsion  of  the  entire  upper  extremity  has  occurred  in  a  number  of 
cases,  especially  in  machinery  accidents.  Apart  from  the  sternoclavicular 
articulation  only  muscles  hold  the  upper  extremity  to  the  trunk,  and  if  the 
clavicle  is  fractured  only  the  rupture  of  muscles,  vessels,  and  nerves  is 
necessary  in  avulsion. 


THE  ANTERIOR  REGION  OF  THE  SHOULDER  10<J 

The  Sternoclavicular  Joint.— The  lack  of  adaptability  between  the 
1 K  >ny  surfaces  forming  this  joint  accounts  largely  for  the  amount  of  motion 
that  occurs  here.  When  the  arm  hangs  at  the  side  the  clavicle  is  in  con- 
tact with  the  socket  only  at  its  lower  angle,  rendering  the  cavity  V-shaped. 
This  allows  the  elevation  of  the  shoulder,  in  which  position  the  bones 
are  in  more  immediate  contact.  Accordingly  in  disease  of  this  joint  the 
motion  of  elevation  of  the  shoulder  is  that  which  produces  the  most  pain. 

Dislocation  of  the  clavicle  from  the  sternum  is  rare  on  account  of  the 
strength  of  the  ligaments  that  bind  them  together,  which  are  stronger 
than  the  clavicle,  and  on  account  of  the  diffusion  of  the  violence  by  means 
of  the  mobility  of  the  scapula  and  the  elasticity  of  the  clavicle.  Hence 
any  violence  which  threatens  the  joint  usually  fractures  the  bone.  The 
dislocation  may  be  complete  or  incomplete  and  occurs  in  the  (1)  forward, 
'_'  backward,  and  (3)  upward  directions,  in  the  order  of  frequency. 
The  relative  frequency  of  these  three  varieties  depends  upon  the  relative 
strength  of  the  ligaments  that  resist  them  and  that  restrict  the  movements 
<>f  the  joint.  Thus,  dislocation  forward  is  resisted  by  the  posterior  and 
anterior  ligaments,  and  the  weakness  of  the  latter  serves  partly  to  explain 
the  relative  frequency  of  the  forward  dislocation.  The  head  of  the 
bone,  displaced  forward  and  usually  inward  and  downward,  rests  on  the 
manubrium  and  carries  with  it  the  sternomastoid  muscle.  It  is  due  to 
forcing  the  outer  end  of  the  clavicle  backward.  In  this  movement  the 
first  ril)  may  form  a  fulcrum  about  which  the  inner  end  of  the  clavicle 
is  carried  forward. 

Dislocation  backward  is  resisted  by  the  same  ligaments  and  in  addition 
the  strong  rhomboid  ligament.  It  may  be  due  to  direct  or  indirect 
violence,  more  often  the  latter,  the  force  pressing  the  shoulder  forward 
and  inward,  as  where  a  person  is  caught  between  two  bodies.  The  head 
of  the  bone,  lying  behind  the  sternum  and  probably  between  it  and 
the  sternothyroid  muscle,  frequently  presses  upon  the  trachea,  causing 
dyspnea,  less  often  upon  the  esophagus,  causing  dysphagia.  In  the  region 
occupied  by  the  displaced  head  of  the  bone  are  most  important  vessels 
and  nerves,  especially  the  internal  jugular  and  innominate  veins,  but  the 
recorded  show  no  serious  pressure  upon  them.  The  head  of  the 
bone  has  been  excised  in  one  case  to  relieve  troublesome  dysphagia.  In 
complete  dislocations  either  forward  or  backward  the  head  of  the  clavicle 
IS  usually  also  displaced  downward,  and  in  all  complete  dislocations  it  is, 
;i-  ;i   rule,  displaced  inward  also. 

In  addition  to  the  ligaments  resisting  backward  dislocation,  dislocation 
upward  is  resisted  by  the  interclavicular  ligament  and  the  inlerartieiilar 
Cartilage;  hence,  the  rarity  of  this  form,  which  implies  a  tearing  of  all 
the  ligaments.  It  is  usually  due  to  forcible  depression  of  the  shoulder,  (he 
firs(  rib  acting  OS  a  fulcrum,  SO  that  the  inner  portion  of  (he  clavicle  is 
elevated.     The  violence  continuing  forces  the  head  inward  and  upward 

behind  the  sternal  portion  of  the  sternomastoid.   The  lack  of  adaptability 

of  the  joint   surfaces  serves  to  explain  die  ease  of  reduction  and  die  diffi- 
culty of  retention  in  most  cases  of  luxation  in  this  joint.      The  recumbent 

position  and  various  Forms  of  dressing  which  act  on  the  clavicle  directly 


170  THE  UPPER  EXTREMITY 

or  through  the  shoulder,  as  in  fracture  of  the  clavicle,  have  been  employed. 
In  connection  with  these  the  injection  of  50  per  cent,  alcohol,  or  a  similar 
fluid,  with  the  object  of  producing  a  mass  of  connective  tissue  around  the 
joint  as  a  sort  of  new  capsule,  has  been  found  useful. 

The  sternoclavicular  joint  is  not  particularly  liable  to  the  ordinary 
diseases  of  joints,  in  spite  of  its  exposed  position  and  constant  motion,  for 
it  is  well  protected  by  its  strong  ligaments  and  interarticular  cartilage 
from  strain  and  injury.  As  the  synovial  sac  is  divided  into  two  by  the 
interarticular  cartilage,  disease  may  commence  in  and  be  limited  to  one 
sac,  but,  as  a  rule,  the  entire  joint  (both  sacs)  becomes  involved.  Owing 
to  the  fact  that  the  anterior  sternoclavicular  ligament  is  the  thinnest  and 
weakest  part  of  the  capsule  swelling  is  first  evident  in  front,  as  a  rule,  and, 
when  spontaneous  perforation  occurs,  the  pus  usually  escapes  anteriorly. 
If,  as  may  happen,  it  escapes  through  the  posterior  ligament  it  may 
readily  reach  the  mediastinum.  The  notable  fact  that  the  disease  of 
this  joint  never  results  in  ankylosis  is  due  chiefly  to  the  entire  lack  of 
adaptation  of  the  two  bony  surfaces  and,  to  a  less  extent,  to  the  constant 
slight  movement  here  and  the  occasional  persistence  of  the  interarticular 
cartilage,  after  arthritis.  The  importance  of  bearing  in  mind  the  relations 
of  this  joint  to  the  great  vessels  behind  it  is  illustrated  by  a  case  reported 
by  Mr.  Hilton  in  which  a  large  abscess  in  the  joint  received  pulsation 
from  the  subjacent  subclavian  or  innominate  artery  and  was  first  thought 
to  be  an  aneurysm. 

The  Acromioclavicular  Joint. — The  acromioclavicular  joint  depends 
for  its  strength  upon  its  ligaments,  for  its  shallow  flat  joint  surfaces  are 
bevelled  from  above  downward  and  inward  and  offer  no  obstacle  to  the 
upward  dislocation  of  the  outer  end  of  the  clavicle.  This  fact  explains 
why  this  is  the  common  form  of  dislocation  in  this  joint.  The  capsule 
and  ligaments  of  the  joint  proper  are  lax  and  weak,  so  that  effusion  into 
the  joint  is  soon  visible.  It  is  the  strong  coracoclavicular  ligament  (conoid 
and  trapezoid  divisions)  upon  which  the  strength  of  the  connection  between 
clavicle  and  scapula  depends. 

The  upward  dislocation  of  the  outer  end  of  the  clavicle  may  be  com- 
plete or  partial,  and  in  the  former  case  the  coracoclavicular  as  well  as  the 
acromioclavicular  ligaments  are  torn,  in  the  latter  case  the  former  may 
be  partly  torn  or  merely  stretched.  In  complete  dislocation  the  outer 
end  of  the  clavicle  rides  up  above  the  acromion  and  may  be  displaced 
outward  over  the  latter.  The  cause  is  usually  a  blow  upon  the  point  of 
the  shoulder,  probably  associated  with  a  vigorous  contraction  of  the  tra- 
pezius, whereby  the  clavicle  is  prevented  from  becoming  depressed  with 
the  acromion.  The  rarity  of  downward  or  subacromial  dislocation  of  the 
outer  end  of  the  clavicle  is  explained  by  the  oblique  direction  of  the 
joint  surfaces.  The  cause  in  most  cases  was  direct  violence  applied  to 
the  outer  end  of  the  clavicle. 

Whereas  reduction  is  commonly  easy  in  both  forms,  retention  is  diffi- 
cult, as  there  is  nothing  in  the  shape  of  the  bones  to  hold  them  together 
and  the  ligaments  are  torn.  In  the  common  upward  form  upward 
pressure  of  the  shoulder  through  the  arm  and  downward  pressure  on  the 


THE  ANTERIOR  REGION  OF  THE  SHOULDER  1J1 

outer  end  of  the  clavicle  are  accomplished  by  various  retentive  dressings, 
but  the  necessary  continuous  retention  is  very  difficult.  As  in  dislocation 
of  the  sternoclavicular  joint  the  injection  of  irritants,  like  50  per  cent, 
alcohol,  to  stimulate  peri-articular  connective-tissue  formation,  which 
afterward  contracts  and  helps  to  hold  the  bones  together,  I  have  found 
useful,  especially  in  the  incomplete  forms.  Some  patients  are  seriously 
disabled  by  this  accident,  others  but  little. 

In  this  connection  it  may  be  noticed  that  the  movements  of  this  joint 
allow  the  glenoid  cavity  to  maintain  or  alter  its  relative  position  in  the 
movements  of  the  shoulder  around  the  sternoclavicular  joint  as  a  centre. 
Thus  in  raising  the  arm  the  extent  of  this  movement  is  much  increased 
by  the  elevation  of  the  glenoid  cavity,  so  as  to  look  upward,  the  scapula 
moving  on  an  anteroposterior  axis  through  this  joint.  Again,  as  the 
shoulder  moves  forward  for  a  blow  or  shove  or  in  a  fall  upon  the  hand, 
the  glenoid  cavity  is  turned  forward,  so  that  it  may  be  as  nearly 
as  possible  at  right  angles  to  the  long  axis  of  the  humerus  which,  it 
it  can  thus  best  support.  In  this  way  a  strong  forward  "blow  from  the 
shoulder"  is  possible.  Otherwise  the  strain  comes  upon  the  capsule  of 
the  joint  and  tends  to  dislocate  the  shoulder.  This  forward  position  of 
the  glenoid  cavity  is  due  to  a  movement  of  the  scapula  on  a  vertical  axis 
passing  through  this  joint.  Impairment  of  this  joint  by  accident  or 
disease  may,  therefore,  cause  a  limitation  in  certain  movements  of  the 
upper  limb  or  an  insecurity  of  the  shoulder  joint. 

Subclavicular  Soft  Parts. — The  interspace  between  the  sternal  and 
clavicular  portions  of  the  pectoralis  major  can  often  be  distinguished  on 
the  surface  just  below  the  clavicle.  The  sternal  portion  is  often  removed 
in  the  operation  for  carcinoma  of  the  breast.  The  clavicular  portion  is 
the  more  superficial  of  the  two.  The  pectoral  fascia  is  firmly  connected 
with  the  pectoralis  major.  We  may  usually  be  sure  that  we  have  divided 
the  pectoralis  major  when  we  reach  a  cellular  layer,  though  Heath 
describes  a  cellular  interval  which  sometimes  lies  between  two  planes  of 
it-  muscle  fibers  and  may  be  mistaken  for  the  space  beneath  it.  On 
removal  of  the  pectoralis  major  we  expose  the  pectoralis  minor,  from 
whose  upper  border,  as  far  as  the  coracoid  process,  a  strong  fascia,  the 
clavipectoral  fascia,  extends  up  to  and  is  continuous  with  the  sheath  of 
the  subclavius  muscle,  and  thence  is  connected  with  the  clavicle.  It  is 
continuous  above  with  the  sheath  of  the  axillary  vein  and  the  deep  cervical 
Fascia.     Mesially  it  is  continuous  with  the  deep  fascia  covering  (he  first 

two  intercostal  spaces.  The  upper  pari  of  this  fascia,  between  die  cora- 
coid process  and  the  first  rib,  is  particularly  firm,  and  is  named  the 
costocoracoid  membrane.  This  fascia  is  pierced  by  the  cephalic  vein,  the 
acromiothoracic  artery,  and  the  anterior  thoracic  nerve,  and  corns  the 

firsl   portion  of  the  axillary  vessels  and  the  brachial  plexus.     The  clavi- 

pectoral  fascia  splits  /<>  ensheath  the  pectoralis  minor  and  unites  below 
it  into  ;i  single  triangular  sheet  which  extends  laterally  to  the  sheath  of 
the  coracobrachialis  and  inferiorly  to  die  axillary  fascia  in  (lie  floor  of 

the  ;ixilla,  the   hollow  of    which    it   serves   to  preserve,  hence   the   name 

pensory  ligament  of  the  axilla" 


172  THE  UPPER  EXTREMITY 

The  axillary  vein  lies  below  and  internal  to  the  artery,  which  it 
overlaps,  owing  to  its  greater  size.  Hence  when  the  axillary  artery  is  tied 
in  its  first  portion  the  aneurysm  needle  is  passed  from  below,  to  avoid 
injury  to  the  vein.  The  axillary  artery  is  crossed  in  front  by  the  cephalic 
vein  in  its  passage  to  reach  the  axillary  vein.  A  part  of  or  the  entire 
cephalic  vein  occasionally  crosses  in  front  of  the  clavicle  to  join  the 
external  jugular  vein.  One  of  the  cords  of  the  brachial  plexus  lies  in 
contact  with  and  on  the  same  plane  as  the  artery  and  may  be  and  has  been 
mistaken  for  it  in  ligation  of  the  artery.  These  main  vessels  and  nerves 
are  surrounded  by  more  or  less  areolar  and  fatty  tissue  containing  lym- 
phatic vessels  and  the  subclavicular  group  of  nodes,  which  may  be 
involved  secondarily  to  those  of  the  axilla,  with  which  they  are  continu- 
ous. Their  efferent  vessels  form  the  subclavian  trunk  and  in  addition 
communicate  with  the  supraclavicular  group  of  the  deep  cervical  nodes 
above.  Along  this  areolar  tissue  deep  infection  and  abscess  may  extend 
from  the  neck  to  the  axilla,  and  vice  versa. 

The  Posterior  or  Scapular  Region. 

The  skin  covering  this  region  is  firm,  and  there  is  but  little  subcutaneous 
tissue.  The  thick  deep  fascia,  by  its  attachment  to  bone  around  the 
origin  of  the  supra-  and  infraspinatus  and  the  teres  minor  muscles  which 
it  covers,  encloses  them  in  an  osseo-aponeurotic  compartment,  open  only 
toward  the  insertion  of  the  muscles  on  the  great  tuberosity  of  the  humerus. 
Hence  in  case  of  abscess  under  this  fascia  or  ecchymosis  from  fracture 
of  the  scapula  the  pus  or  blood  cannot  readily  reach  the  surface,  but 
follows  the  muscle  sheaths  to  the  humeral  head  and  appears  from  beneath 
the  deltoid.  The  firmness  of  this  fascia  is  such  that  it  is  difficult  to  decide 
whether  dense  tumors  growing  from  it  are  connected  with  the  fascia  or 
the  bone.  The  scapula  is  held  in  place  by  the  coraco-  and  acromioclavicu- 
lar ligaments  and  by  the  serratus  magnus,  rhomboids,  trapezius,  and 
levator  scapulae  muscles.  The  so-called  "winged  scapula,"  or  luxation 
of  the  scapula,  in  which  the  lower  part  of  or  the  entire  vertebral  border 
projects  backward  from  the  chest  wall,  is  due  to  paralysis  of  the  lower 
part  or  the  whole  of  the  serratus  magnus  muscle,  which  is  supplied  by  the 
long  thoracic  nerve.  In  ankylosis  of  the  shoulder  joint  the  mobility  of 
the  scapula  diminishes  the  functional  disability. 

Fracture  of  the  body  of  the  scapula  is  comparatively  rare,  owing  to  the 
mobility  of  the  bone,  the  adaptation  of  its  shape  to  the  curve  of  the  thorax 
it  covers,  its  thick  muscular  covering,  the  elasticity  of  the  ribs  beneath, 
and  the  soft  muscular  pad  of  the  subscapularis  and  serratus  magnus 
between  it  and  the  chest  wall.  In  case  of  fracture  the  fragments  are 
spl  nted  by  the  muscles  attached  on  both  sides  of  it,  which  prevent  much 
^displacement.  The  acromion  is  more  exposed  to  injury  and  fracture  than 
other  parts  of  the  bone.  Some  consider  many  cases  of  supposed  fracture 
of  the  acromion  as  examples  of  epiphyseal  separation  from  the  spine, 
which  may  occur  before  the  twentieth  year,  when  the  epiphyseal  union 
ossifies.    But  clinically  most  cases  are  found  to  be  nearer  the  end  of  the 


THE  POSTERIOR  OR  SCAPULAR  REGION  173 

acromion,  i.  c,  just  in  front  of  the  acromioclavicular  joint.  The  dense 
fibrous  tissue,  which  covers  this  process  and  is  derived  from  the  two 
muscles  attached  to  it  (deltoid  and  trapezius),  and  its  thick  periosteum 
help  to  explain  why  much  displacement  is  uncommon  and  why  many 
fractures  are  subperiosteal  and  crepitus  is  wanting.  When  the  fracture 
is  in  front  of  the  acromioclavicular  joint  the  deltoid  may  pull  the  frag- 
ment slightly  downward,  causing  a  little  flattening  of  the  tip  of  the 
shoulder,  but  there  can  be"no  displacement  of  the  scapula  and  arm.  When 
the  fracture  is  behind  the  joint  the  scapula  may  still  be  connected  by  the 
coracoclavicular  ligaments  to  the  clavicle,  and  there  can  be  but  little  if 
any  displacement  of  the  arm.  Bony  union  is  said  to  be  the  exception. 
It  should  be  remembered  that  in  some  cases  the  union  of  the  acromion 
and  spine  does  not  ossify,  so  that  the  presence  of  motion  and  fibrous 
union  between  these  two  parts  does  not  necessarily  imply  fracture  or  an 
epiphyseal  separation. 

Fracture  of  the  coracoid  process  may  occasionally  occur  as  a  result  of 
violence  or  muscular  action.  Usually  it  is  only  one  of  several  fractures 
resulting  from  severe  violence.  In  some  cases  the  line  of  fracture,  being 
Dear  the  base  of  the  process  in  the  line  of  the  epiphyseal  cartilage,  which 
ossifies  during  the  fifteenth  year,  has  suggested  that  the  case  was  one  of 
epiphyseal  separation.  Although  three  powerful  muscles  are  attached  to 
the  coracoid  process,  displacement  is  usually  slight,  owing  to  the  attach- 
ment of  the  coracoclavicular  ligaments,  which  are  seldom  torn. 

The  rare  fracture  of  the  surgical  neck  of  the  scapula  involves  the  separa- 
tion of  the  coracoid  process  and  the  glenoid  fossa,  together  with  the 
triceps  attachment,  from  the  rest  of  the  bone.  The  arm  is  displaced 
downward,  as  in  a  subglenoid  dislocation,  if  the  coracoclavicular,  coraco- 
acrouiial,  and  spinoglenoid  ligaments  are  torn,  but  these  ligaments  are 
usually  untorn  and  limit  the  displacement.  It  is  easily  distinguished 
from  dislocation  of  the  humerus  by  crepitus,  the  ease  of  reduction,  the 
equal  ens*-  of  recurrence  of  the  displacement,  and  by  the  accompanying 
displacement  of  the  coracoid  process. 

Tumors  of  various  kinds,  especially  osteoma,  enchondrotna,  and  sar- 
coma, grow  from  the  scapula  and  require  partial  or  complete  excision, 
hi  partial  excision  those  parts  which  are  of  special  importance  for  the 
function  of  the  arm  i.  e.,  the  glenoid  fossa,  coracoid  and  acromion 
processes,  should  be  preserved  if  possible.  The  entire  bone  is  removed 
with  or  without  the  arm  in  sarcoma.  In  malignant  tumors  of  the  upper 
end  of  the  humerus  and  some  sarcomata  of  the  axilla  the  upper  extremity, 
scapula,  and  outer  two-thirds  of  the  clavicle  are  removed  (interscapulo- 
thoracic  amputation  of  the  arm  I,  after  first  ligating  the  subclavian  artery. 
The    latter    renders    the    operation     bloodless  except     for   the    posterior 

scapular  artery  along  the  vertebral  border  and  the  suprascapular  artery 

in  the  supra-  and  infra  spinous  fossa?,  these  arteries  being  branches  of  the 
(irt  portion  of  the  subclavian.  Iii  complete  excision  of  the  scapula  (with- 
out ligature  of  the  subclavian)  the  subscapular  artery,  which  runs  along 

Dear  the  lower  bonier  of  the  subscapularis  muscle  and  gives  oil'  the  large 

dorsalu   scapulas   branch  crossing  the  axillary   border  onto  the  infra- 


174  THE  UPPER  EXTREMITY 

spinous  fossa,  must  also  be  taken  into  account.  This  branch  of  the 
axillary  artery  anastomoses  with  the  posterior  scapular  and  suprascapular 
branches  of  the  subclavian,  and  is  an  important  factor  in  the  collateral 
circulation  after  ligature  of  the  third  portion  of  the  subclavian  or  the  first 
portion  of  the  axillary  artery.  The  anastomoses  on  the  acromion  between 
the  suprascapular  branch  of  the  subclavian  and  the  acromiothoracic  and 
circumflex  branches  of  the  axillary  assist  in  this  collateral  circulation.  For 
resection  of  the  scapula  a  horizontal  incision  along  the  spine  and  a  vertical 
one  along  the  vertebral  border  (Ollier's)  are  very  serviceable. 

The  suprascapular  nerve  is  a  branch  of  the  fifth  cervical  and  receives 
a  branch  from  the  third  and  fourth  cervical  nerves,  from  which  is  derived 
the  phrenic  nerve.  The  latter  also  communicates  with  the  nerve  to  the 
subclavius  and  with  the  supra-acromial  nerve,  and  these  connections 
explain  the  reflex  relations  between  the  diaphragm  or  liver  and  the 
shoulder,  i.  e.,  hiccough  from  inflammation  of  the  shoulder  and  pain  in 
the  right  shoulder  and  shoulder-tip  pain  in  perihepatitis,  gall-bladder 
lesions,  etc. 

The  External  or  Deltoid  Region. 

This  is  equal  in  extent  to  that  of  the  deltoid  muscle,  which  covers  the 
upper  end  of  the  humerus  and  the  muscles  inserted  into  it,  the  shoulder 
joint,  the  coracoid  process  and  its  muscles,  and  the  coraco-acromial 
ligament.  The  subcutaneous  fatty  layer  over  the  deltoid  is  often  well- 
developed,  and  is  a  favorite  situation  for  lipoma.  The  deep  fascia 
ensheaths  the  deltoid  and  is  closely  bound  to  it.  In  subglenoid  or  sub- 
coracoid  dislocation  of  the  shoulder  the  head  of  the  humerus  no  longer 
bolsters  out  the  deltoid,  so  that  the  latter  is  flattened  and  hangs  straight 
down  from  the  acromion  process,  which  is  thereby  rendered  more  promi- 
nent and  angular.  Moreover,  the  attachments  of  the  deltoid  being  more 
widely  separated  than  normal,  the  muscle  is  put  on  the  stretch,  which  still 
further  flattens  the  region  and  causes  a  fold  at  the  insertion  of  the  muscle. 
To  relax  the  deltoid  the  dislocated  arm  is  usually  held  in  the  abducted 
position.  If  this  position  is  exaggerated,  so  that  the  deltoid  is  very  lax, 
the  fingers  may  be  thrust  beneath  the  acromion  into  the  gap  left  by  the 
dislocated  head  of  the  humerus,  and  in  thin  subjects  the  glenoid  cavity 
may  even  be  felt. 

The  deltoid  region  may  be  flattened  and  a  depression  be  felt  beneath 
the  acromion  in  certain  cases  where  the  head  sinks  away  from  its  socket, 
owing  to  paralysis  and  atrophy  of  the  muscle,  which  is  supplied  by  the 
circumflex  nerve  (Fig.  61).  This  nerve  winds  around  the  surgical  neck 
of  the  humerus  a  little  above  the  posterior  circumflex  artery,  which  is 
5  cm.  (2  in.)  below  the  acromion.  The  nerve  may  be  torn,  bruised,  or 
stretched  in  dislocations  of  the  shoulder,  in  violent  attempts  at  their 
reduction,  in  fractures  of  the  surgical  neck  of  the  humerus,  in  some  birth 
palsies,  and  it  may  very  rarely  be  bruised  in  contusion  of  the  shoulder. 
As  it  also  supplies  the  shoulder  joint  an  inflammation  of  the  latter  extend- 
ing along  the  nerve  may  cause  a  neuritis  and  lead  to  paralysis  of  the 
muscle  (Erb).     This  nerve  also  gives  off  a  cutaneous  branch  which, 


PLATE  XII 


FIG.  61 


SUBSCAPULAR 
ARTERY 


CIRCUM  FLEX 
NERVE 


POSTERIOR    CIRCUM- 
FLEX   ARTERY 


MUSCULO-SPIRAL 
NERVE 

SUPERIOR 
PROFUNDA 
ARTERY 


Posterior  Region  of  the  Shoulder.     Right  side.     (Joessel.) 


THE   EXTERNAL  OR  DELTOID  REGION  175 

winding  around  the  posterior  border  of  the  muscle,  supplies  the  skin 
over  its  louver  third  (and  below  it).  Thus,  according  to  Anger,  we  may 
test  the  sensibility  of  this  cutaneous  branch  after  dislocations  of  the 
shoulder,  and  thereon  base  our  prognosis  as  to  the  future  condition  of  the 
muscle,  for  it  is  not  infrequently  paralyzed  temporarily  or  permanently. 

The  deltoid  is  not  the  only  abductor  of  the  arm,  being  assisted  by  the 
supraspinatus,  and  in  initiating  this  movement  the  latter  is  probably 
the  most  active;  but  in  paralysis  of  the  deltoid  the  power  of  abduction  is 
usually  slight.  In  excision  of  the  shoulder  joint  the  nearer  the  incision 
is  made  to  the  anterior  border  of  the  deltoid  the  less  of  the  muscle  will 
be  paralyzed  by  cutting  its  nerve  supply  and  the  smaller  will  be  the 
branches  of  the  posterior  circumflex  artery  to  be  divided. 

Beneath  the  deltoid,  in  the  layer  of  loose  connective  tissue  which  facili- 
tates the  movements  of  the  underlying  head  of  the  humerus,  is  the 
subdeltoid  or  subacromial  bursa,  which  still  further  facilitates  these 
movements.  As  its  name  implies,  this  bursa  also  extends  beneath  the 
acromion  process  and  the  coraco-acromial  ligament,  and  this  portion  is 
sometimes  partly  separated  from  the  subdeltoid  portion  by  a  constriction. 
Beneath  the  bursa  are  the  great  tuberosity  of  the  humerus  and  the  supra- 
spinatus tendon,  but  there  is  no  communication  with  the  joint  except  when 
the  supraspinatus  tendon  is  ruptured  in  dislocation.  This  bursa  may 
hold  about  an  ounce  when  distended  with  fluid,  as  it  sometimes  is,  causing 
an  undue  prominence  of  the  deltoid.  In  case  of  abscess  of  this  bursa  the 
pus  may  reach  the  surface  at  either  edge  of  the  muscle,  usually  the  ante- 
rior edge,  rarely  through  it.  From  the  point  of  view  of  operative  incision 
the  shoulder  joint  is  only  covered  by  the  skin,  the  deltoid,  and  the  capsule. 

The  Shoulder  Joint. — The  shoulder  joint  is  one  that  relies  for  its 
strength  largely  upon  the  surrounding  muscles,  a  variety  of  joint  most  liable 
to  dislocation.  The  laxity  of  the  capsule  (especially  its  inferior  part)  and 
the  fact  that  the  articular  surfaces  are  held  together  by  muscular  action 
aided  by  atmospheric  pressure  is  shown  by  the  admission  of  air  into  the 
joint,  dissected  free  of  its  muscular  covering.  Thereupon  the  head  of 
the  humerus  falls  away  from  the  glenoid  cavity  by  a  considerable  interval , 
Tin-  same  occurs  in  cases  of  old  standing  paralysis  of  the  deltoid.  The 
acromion  and  coracoid  processes,  and  the  coraco-acromial  ligament 
connecting  them,  form  an  arch  above  the  joint,  protecting  it  but  separated 
from  it  by  the  interposed  tendon  of  the  supraspinatus  and  the  capsule. 

The  muscles  strengthening  the  capsule  arc  the  subscapular^  in  front, 
ili<'  supraspinatus  above,  and  the  infraspinatus  and  teres  minor  behind. 
The  tendons  of  these  muscles  are  blended  with  the  capsule  in  their  passage 
to  the  small  and  great  tuberosities  of  (he  humeral  head.  They  arc  con- 
tinuous with  one  another  and  are  assisted  in  supporting  (he  join!  by  the 

long  head  of  (In-  triceps  below  and  the  long  head  of  the  biceps  above. 
Tin-  latter  tendon   in  its  passage  through   the  bicipital  groove,  which   is 

converted  into  a  canal  by  the  transverse  ligament,  is  accompanied  by  a 
tubular  prolongation  of  the  synovial  membrane  forming  a  hind  of  vaginal 
sheath  for  it.  There  i--  another  constant  (pip  in  the  capsule  by  which  the 
synovial  sac  communicates  with  the  subscapular  bursa,  ;i  huge  pouch 


176  THE  UPPER  EXTREMITY 

between  the  upper  part  of  the  subscapularis  and  the  root  of  the  coracoid 
process,  together  with  the  adjoining  part  of  the  neck  of  the  scapula.  The 
crescentic  gap  leading  from  the  joint  into  this  bursa  lies  just  in  front  of 
the  upper  end  of  the  inner  or  anterior  margin  of  the  glenoid  cavity, 
between  the  superior  and  middle  glenohumeral  bands.  A  bursa  beneath 
the  infraspinatus  rarely  communicates  with  the  joint.  The  capsule  is 
unprotected  antero-inferiorly  between  the  subscapularis  and  the  long 
head  of  the  triceps,  where  the  head  can  be  felt  by  the  hand  in  the  axilla. 
The  axillary  vessels  and  nerves  (Figs.  64,  68)  lie  to  the  inner  side  of 
the  joint,  separated  from  it  by  the  subscapularis  tendon. 

In  joint  disease  with  effusion  the  shoulder  appears  full  and  rounded  by 
reason  of  the  distended  capsule,  which  may  cause  a  separation  of  the  two 
bones  of  more  than  12  mm.  (^  in.)  (Braune).  In  artificial  distention  the 
arm  becomes  slightly  extended  and  rotated  inward,  a  position  commonly 
found  in  joint  disease  and  perhaps  due  partly  to  the  rigid  contraction  of 
the  muscles,  of  which  the  latissimus  dorsi  may  have  a  slight  advantage  and 
be  responsible  for  the  extension  and  inward  rotation.  Special  prominences 
occur  in  the  bicipital  and  subscapular  diverticula.  Thus  a  swelling  often 
appears  at  an  early  stage  in  the  groove  between  the  deltoid  and  great  pec- 
toral muscles.  This  swelling  is  sometimes  bilobed  on  account  of  the 
unyielding  biceps  tendon.  Fluctuation  can  best  be  felt  through  the  axilla, 
at  the  uncovered  part  of  the  capsule  below  the  subscapularis.  If  sup- 
puration occurs  the  pus  usually  escapes  through  one  of  the  diverticula, 
most  often  the  one  around  the  biceps  tendon.  In  the  latter  case  it  may 
extend  some  distance  along  and  beyond  the  bicipital  groove.  If  it  escapes 
through  the  subscapular  bursa  it  is  apt  to  spread  between  the  muscle 
and  the  scapula  and  point  at  the  lower  and  dorsal  part  of  the  axilla. 
Although  the  shoulder  joint  is  liable  to  all  forms  of  joint  disease,  the  latter 
are  not  particularly  common  here.  This  fact  is  partly  due  to  its  ample 
covering  of  soft  parts,  the  mobility  of  the  shoulder  girdle  (diminishing 
strains),  the  weight  of  the  upper  extremity  resisting  the  pressure  between 
the  joint  surfaces  and  the  laxity  of  the  capsule  and  its  synovial  lining 
lessening  the  tendency  to  joint  tension  from  effusion.  As  the  result  of 
disease  the  various  forms  of  ankylosis  occasionally  occur,  and  in  such 
cases  Tillaux  has  suggested  division  of  the  clavicle  and  the  formation  of 
a  false  joint  to  afford  more  free  movement. 

The  long  tendon  of  the  biceps  strengthens  the  upper  part  of  the  joint, 
keeps  the  humerus  against  the  glenoid  cavity,  and  prevents  it  from  being 
pulled  down  when  the  arm  is  abducted.  It  also  prevents  the  deltoid  from 
pressing  the  head  of  the  bone  too  strongly  against  the  acromion.  It  is 
rarely  ruptured  and  seldom  displaced  from  its  groove  unless  one  of  the 
tuberosities  is  torn  away,  as  occasionally  occurs  in  dislocation  of  the 
shoulder.  The  inner  margin  of  the  glenoid  cavity  is  the  stronger  and  more 
prominent,  especially  below,  a  fact  which  indicates  an  attempt  to  fortify 
a  weak  part  of  the  joint  where  the  head  most  often  leaves  the  socket  in 
dislocation. 

When  the  arm  hangs  at  the  side  the  entire  head  may  be  to  the  outer 
side  of  the  coracoid  process  in  this  position,  but  the  shape  of  this  process 


PLATE   XIII 


FIG.  62 


Right  Shoulder  Joint.     Anteroposterior.     Arm  rotated  outward. 
Male,   aged    thirty-three    years. 


l  I  |)|»i  border  ><i  scapula 

i  Attachment  <»i   ipine  ol  scapula 

::  Bpine  "i   scapula 

l  Acromion. 


.">.  Coracoid  pro 

ii  Glenoid  cavity. 

7  Second  ril». 

8  l  ifth  iil>. 


THE  EXTERNAL  OR  DELTOID  REGION  177 

varies  and  often  overlies  the  inner  part  of  the  head.  Especially  when 
the  point  of  the  shoulder  droops,  the  tip  of  the  coracoid  is  often  in 
contact  with  the  lesser  tuberosity  and  a  bursa  (subcoracoid)  intervenes 
between  them  (Goldthwaite).  With  the  arm  hanging  at  the  side  the 
glenoid  cavity  looks  outward  and  forward,  nearly  midway  between  the 
sagittal  and  frontal  planes  of  the  body,  and  at  least  two-thirds  of  the  head 
of  the  humerus  are  not  in  contact  with  it.  The  glenoid  fossa  is  less  than  half 
as  large  as  the  articular  portion  of  the  head  of  the  humerus  on  horizontal 
section,  and  about  two-thirds  as  large  on  vertical  section.  Thus  a  consid- 
erable portion  of  the  head  of  the  humerus  is  always  out  of  the  socket  and 
in  contact  with  the  capsule,  and  in  abduction  of  the  arm  to  90  degrees  the 
head  of  the  bone  presses  against  and  puts  on  the  stretch  the  lower  unpro- 
tected part  of  the  capsule,  between  the  subscapularis  and  triceps  tendons. 
It  is  in  this  position,  with  or  without  outward  rotation,  that  dislocation 
of  the  shoulder  is  most  likely  to  occur. 

In  abduction  of  the  arm  to  a  right  angle  the  great  tuberosity  abuts 
against  the  upper  edge  of  the  glenoid  cavity  and  the  upper  end  of  the 
outer  aspect  of  the  humerus  against  the  coraco-acromial  arch.  This  is 
true  whether  the  arm  is  abducted  laterally  or  in  the  forward  position,  as  in 
falls  on  the  hand.  Further  abduction  is  due  to  the  rotation  of  the  scapula, 
but  if  the  latter  is  kept  from  rotating  by  being  held  mechanically  or  by 
a  muscular  spasm  (serratus  magnus),  and  if  the  motion  of  abduction 
is  continued,  a  new  centre  of  motion  is  formed  at  the  point  of  contact  of 
the  humerus  with  the  coraco-acromial  arch,  and  the  prominence  of  the 
head  is  forced  down  against  the  lower  and  inner  tense  part  of  the  cap- 
sule, rupturing  it  at  its  thinnest  and  weakest  part.  Such  is  the  common 
mechanism  of  dislocation  in  cases  due  to  indirect  or  to  muscular  violence. 
Rarely  the  head  may  leave  the  socket  more  anteriorly,  or  very  rarely 
posteriorly. 

The  infrequency  of  the  injury  in  the  first  two  decades  of  life  is  inter- 
esting in  connection  with  Kronlein's  theory  that  in  this  period  fracture 
of  the  clavicle  is  the  equivalent  of  dislocation  of  the  shoulder  by  direct 
violence,  and  dislocation  of  the  elbow  the  equivalent  of  dislocation  of 
the  shoulder  by  indirect  violence. 

Dislocations  of  the  shoulder  are  as  numerous  as  all  other  dislocations 
combined,  perhaps  more  so.  This  frequency  is  fully  explained  by  (1)  the 
structure  of  the  joint  (the  shallowness  of  the  glenoid  fossa,  the  large  size 
of  the  humeral  head,  the  freedom  of  motion,  the  long  leverage  of  (he  arm, 
(he  thinness  and  laxity  of  the  capsule  and  its  dependence  upon  the  muscles 
for  it^  strength,;  and  (2)  the  exposure  of  the  shoulder  to  indirect  and 
direct  violence.    Dislocations  of  the  shoulder  arc  classified,  according  to 

the  displacement  of  the  humeral  head,  into  (1  )  anterior  or  subcoracoid, 
the  common  form;  (2)  downward  or  subglenoid,  not  common;  (•'!)  back- 
ward or  subspinous,  rare;  and  (4)  upward  or  snpraglenoid,  wry  rare. 
(  )nl\  the  firs!  two  forms  demand  our  consideration. 

In  subcoracoid  dislocations  the  heail  of  the  humerus  escaping  through 
the  rent   in  the  antcro-inferior  part  of  the  capsule  is  displaced  primarily 
downward   and  SOmewhal    forward.      Indeed,  sonic  downward   displace- 
12 


178 


THE  UPPER  EXTREMITY 


merit  is  necessary  to  allow  the  head  to  get  beneath  the  coracoid.  But 
the  further  downward  displacement  is  resisted  by  the  untorn  part  of  the 
capsule  (posterior  and  superior  parts),  whose  attachment  to  the  ana- 
tomical neck  serves  as  a  new  centre  of  motion,  so  that  when  the  elbow  is 
lowered  after  abduction  has  ceased,  the  head,  the  short  arm  of  the  lever, 
rises  along  the  inner  side  of  the  glenoid  cavity.  This  secondary  displacement 
to  a  final  position,  approximately  beneath  the  coracoid  (subcoracoid),  is 
also  partly  effected  by  the  contraction  of  such  muscles  as  the  pectoralis 
major,  latissimus  dorsi,  and  deltoid.  The  extent  of  this  secondary  inward 
displacement  is  determined  largely  by  the  resistance  of  the  untorn  portion 

of  the  capsule,  the  continuance 
fig.  63  of  the  dislocating  violence,  and 

the  degree  of  contraction  of  the 
adductor  muscles.  Thus  the 
head  may  rarely  be  displaced  in- 
ternal to  the  coracoid  process, 
giving  rise  to  the  subvariety 
"intracoracoid"  (Fig.  63). 

In  the  subcoracoid  form  the 
head  of  the  bone  lies  behind  the 
coraco-brachialis  and  the  short 
head  of  the  biceps  and  against 
the  edge  of  the  glenoid  fossa, 
or  the  side  of  the  neck  of  the 
scapula  just  internal  to  it.  The 
posterior  part  of  the  anatomical 
neck  may  rest  on  the  anterior 
lip  of  the  glenoid  cavity.  In  the 
intracoracoidal  or  subclavicular 
variety  it  lies  farther  backward 
and  inward  on  the  neck  of  the 
scapula  and  against  the  chest 
wall  on  the  serratus  magnus, 
having  passed  behind  the  mus- 
cles arising  from  the  coracoid 
process.  The  head  is  thus  in- 
ternal, anterior,  and  a  little  infe- 
rior to  its  normal  position. 
The  subscapularis  muscle  is  sometimes  pressed  inward  and  separated 
from  the  scapula  by  the  interposed  humeral  head,  but  in  many  cases 
it  is  torn  from  its  lower  border  upward  to  a  greater  or  less  extent.  Thus 
the  subscapularis  may  intervene  in  whole  or  in  part  between  the  coracoid 
process  and  the  head,  or  the  latter,  escaping  in  front  of  the  muscle,  may 
lie  close  against  the  beak  of  the  coracoid,  behind  the  coracobrachialis 
and  short  head  of  the  biceps.  The  attachment  to  the  humerus  of  the 
supraspinatus  is  probably  often  torn,  that  of  the  infraspinatus  less  often, 
or,  in  place  of  this  rupture  of  the  tendons,  one  or  more  facets  of  the  great 
tuberosity  may  be  torn  off.    This  latter  accident  is  of  importance  because 


Intracoracoid  dislocation. 


THE  EXTERNAL  OH  DELTOID  REGION  17«.| 

it  open*  the  way  fur  the  long  biceps  tendon  to  escape  from  its  groove,  slip 
over  the  head,  and  become  engaged  between  the  head  and  the  glenoid 
cavity,  where  it  may  otter  a  serious  obstacle  to  reduction.  The  rupture 
or  avulsion  of  the  supra-  and  infraspinatus  tendons,  and  their  consequent 
retraction  under  the  acromion,  may  impair  the  subsequent  motion  of  the 
joint  by  their  loss  of  control  over  the  humerus.  They  may  also  become 
interposed  between  the  head  and  its  socket,  so  as  to  oppose  complete 
reduction,  or  they  may  open  up  the  subacromial  bursa  and  favor  the 
recurrence  of  dislocation  by  lengthening  and  weakening  the  capsule. 
AVhen  the  coracoid  process  rests  against  the  lesser  tuberosity,  in  drooping 
of  the  shoulder  (p.  177),  this  tuberosity  forms  a  new  centre  of  motion, 
and  the  biceps  tendon  then  tends  to  draw  the  head  downward  and 
inward  and  thus  becomes  a  cause  of  recurrent  dislocation  (Goldthwaite). 
The  axillary  vessels  and  nerves  are  pressed  inward  and  sometimes  rup- 
tured, contused,  or  compressed,  causing  pain,  edema,  etc. 

In  the  subglenoid  variety  the  head  usually  rests  against  the  flattened 
upper  end  of  the  axillary  border  of  the  scapula  on  the  inner  side  of  the 
triceps  tendon,  the  latter  preventing  its  displacement  directly  downward. 
It  thus  lies  below  and  a  little  internal  and  anterior  to  its  normal  position. 
It  also  lies  beneath  the  subscapulars  tendon,  which  is  much  stretched  or 
torn.  The  rent  in  the  capsule  differs  from  that  in  the  subcoracoid  form 
in  not  extending  so  far  upward  along  the  anterior  edge  of  the  glenoid 
cavity.  The  resistance  of  this  untorn  anterior  part  of  the  capsule  seems 
to  be  what  prevents  the  head  from  reaching  the  subcoracoid  position, 
although  in  some  cases  this  dislocation  may  be  transformed  into  a  sub- 
coracoid by  movements  of  the  arm  or  even  by  muscular  action.  The 
supraspinatus  and  often  the  infraspinatus  are  torn  horn  their  attachments, 
or  the  tuberosity  is  avulsed  from  the  humerus.  The  cause  of  the  sub- 
glenoid form  has  almost  always  been  a  forcible  elevation  of  the  arm. 

The  symptoms  in  both  forms  are  mainly  due  to  the  absence  of  the  head 
from  its  normal  position,  the  presence  of  the  head  in  an  abnormal  posi- 
tion, and  the  consequent  altered  position  or  action  of  the  muscles.  The 
absence  of  the  head  from  its  socket  accounts  largely  for  the  flattening 
of  the  deltoid  region,  and,  in  the  subcoracoid  form,  the  empty  glenoid 
socket  can  be  felt  through  the  axilla.  In  the  subglenoid  form  we  can 
feel  tin'  head  through  the  axilla,  lying  below  the  glenoid  fossa,  12  to  25 
mm.  (\  to  1  in.)  below  the  coracoid  process,  while  in  the  subcoracoid 
form  it  forms  a  hard  prominence  of  the  anterior  axillary  wall,  just  below 
tin-  coracoid  process,  and  causes  a  fulness  of  the  outer  part  of  the  infra- 
clavicular fossa.  The  axis  of  the  arm  prolonged  upward  passes  below  or 
interna]  to  the  glenoid  cavity.    The  deltoid  is  stretched  by  the  increased 

separation  of  it-,  attachments,  and  this  not  only  increases  (he  flattening  of 
the  deltoid  region  ;i  nd  the  angular  prominence  of  the  acromion,  but 
CSUSefl  the  arm  to  be  abducted,  which  is  more  marked  iii  the  subglenoid 

variety,  as  in  this  form  the  deltoid  is  more  stretched.  Below  the  promi- 
nent edge  of  the  acromion  we  can  feel  ;i  depression  instead  of  the  natural 

l.i  nee  of  the  tuberosities. 

A    the  head  is  displaced  somewhaf  downward  in  both  forms,  measure- 


180  TEE  UPPER  EXTREMITY 

merit  from  the  angle  of  the  acromion  to  the  external  condyle  of  the 
humerus  should  show  lengthening  as  compared  with  the  opposite  limb. 
But  owing  to  the  relative  position  of  these  two  points  of  measurement, 
in  a  plane  external  to  that  of  the  glenoid  cavity,  abduction  causes  a 
measured  shortening  in  the  normal  arm  and  still  more  so  in  the  dis- 
located arm,  when  the  head  is  displaced  more  or  less  inward.  Hence  the 
measured  lengthening  will  depend  on  the  degree  of  abduction,  and  may 
be  altogether  wanting  or  replaced  by  shortening,  though  seldom  so  in 
the  subglenoid  form,  in  spite  of  the  greater  abduction,  on  account  of  the 
greater  lengthening  in  this  form.  The  vertical  dimension  of  the  axilla 
is  increased  because  the  axillary  folds,  formed  by  the  pectoralis  major 
and  latissimus  dorsi,  are  displaced  downward  with  the  humerus,  to 
which  they  are  attached.  The  elbow  is  flexed  by  reason  of  the  tension 
of  the  biceps.  The  elbow  cannot  be  made  to  touch  the  thorax,  for,  on 
account  of  the  rotundity  of  the  thorax,  both  ends  of  the  straight  humerus 
cannot  touch  it  at  the  same  time,  and  in  a  dislocation  of  the  shoulder  the 
head  of  the  bone  is  practically  in  contact  with  the  thorax.  The  diagnosis 
between  subcoracoid  and  subglenoid  dislocations  can  usually  be  readily 
made  from  the  differences  noted  in  the  symptoms  given  above. 

Reduction. — The  obstacles  to  this  may  be  the  tension  of  the  untorn 
portion  of  the  capsule,  opposing  the  movement  of  the  head  toward  the 
socket,  the  approximation  of  the  sides  of  the  rent  in  the  capsule,  the 
interposition  of  portions  of  the  capsule  or  of  the  biceps  tendon,  the  con- 
traction and  rigidity  of  the  muscles,  the  edge  of  the  glenoid  cavity,  and, 
rarely,  the  interposition  of  the  subscapularis  tendon. 

The  most  frequent  obstacles  are  the  opposition  of  the  untorn  anterior 
part  of  the  capsule  and  the  contraction  of  the  muscles,  and  these,  as  well 
as  most  other  obstacles,  may  be  avoided  by  abduction  and  outward  rotation 
of  the  arm.  Traction  in  this  position,  with  or  without  direct  pressure  on 
the  head  toward  the  glenoid  cavity,  is  successful  in  the  great  majority  of 
cases.  Inward  rotation  may  increase  the  success  of  this  method.  Suc- 
cess in  methods  employing  traction,  in  fact,  in  all  methods,  is  also  largely 
dependent  upon  the  efficient  fixation  of  the  scapula  by  the  surgeon,  his 
assistant,  bandages,  or  apparatus.  Stimson1  has  successfully  employed  a 
modification  of  this  method  by  exerting  continued  traction  by  a  weight 
on  the  abducted  arm,  the  latter  passing  through  a  hole  in  a  canvas  cot. 
The  continued  traction  of  the  weight  tiring  out  the  muscular  contraction, 
reduction  occurs  painlessly  and  spontaneously  within  six  minutes. 
Similarly  the  weight  of  the  body  may  be  used  to  produce  the  traction,  by 
the  assistant  raising  up  the  abducted  arm  of  the  patient,  who  lies  on 
the  floor.  Traction  upward,  though  formerly  employed,  is  objectionable 
on  account  of  the  risk  of  increasing  the  laceration  of  the  capsule  and  of 
injuring  the  axillary  vessels  by  stretching  them  around  the  head  of  the 
humerus.  Although  this  method  is  theoretically  suggested  by  the  position 
of  the  head  in  the  subglenoid  variety,  yet,  on  account  of  the  risks  men- 
tioned, trial  should  first  be  made  of  direct  reposition  by  pressure  on  the 

1  Fractures  and  Dislocations,  fourth  ed.,  p.  564. 


THE  EXTERNAL  OR  DELTOID  REGION  |S| 

head,  or  this  combined   with  traction  and  rotation  in  the  abducted 
position. 

In  the  methods  of  reduction  by  manipulation,  rotation  inward  has  long 
been  employed  to  turn  the  head  of  the  bone  into  the  socket  opposite  to 
which  it  had  been  brought  by  traction.  Inward  rotation  constitutes 
the  last  step  in  the  pure  manipulative  method  now  most  in  use,  that  of 
Kocher.  This  is  especially  applicable  in  the  subcoracoid  form.  In 
Kocher's  method  the  flexed  elbow  is  pressed  against  the  side  (adduction)  and 
the  arm  rotated  outward  until  the  forearm  points  directly  outward ;  the  arm, 
rotated  outward,  is  then  carried  forward  (upward)  and  slightly  inward, 
and  rotated  inward,  carrying  the  hand  over  to  the  opposite  shoulder. 
Reduction  occurs  in  the  final  rotation  inward  or  in  the  movement  forward 
and  inward.  Of  course,  flexion  of  the  elbow,  in  this  and  other  methods  of 
reduction,  relaxes  the  biceps  and  provides  a  lever  for  the  rotation  and 
other  movements  in  the  manipulation.  Farabeuf  thus  explains  the 
mechanism  of  the  manipidation.  The  untorn  posterior  portion  of  the 
capsule  is  the  efficient  agent.  This  is  tightened  by  the  adduction,  so  as  to 
prevent  the  posterior  surface  of  the  humerus  from  moving  inward  or 
forward  when  the  arm  is  rotated  outward.  Hence  the  attachment  of  this 
part  of  the  capsule  serves  as  a  fixed  point  about  which  the  head  starts  to 
roll  or  wind  outward,  in  outward  rotation,  toward  the  outer  aspect  of  the 
socket.  This  movement  also  relaxes  the  tendons  of  the  scapular  muscles 
and  removes  them  from  the  fossa.  In  the  forward  movement,  with  slight 
adduction,  the  head,  forming  the  short  arm  of  the  lever  and  turning  upon 
the  same  fixed  point,  is  thrown  backward  and  farther  outward  toward  a 
point  opposite  the  socket,  but  separated  from  it  by  the  capsule,  so  that  the 
final  inward  rotation,  unwinding  the  capsule,  leaves  the  head  in  place.  In 
the  forward  movement  the  upper  portion  of  the  capsule,  the  deltoid,  and 
the  coracobrachial  are  relaxed,  and  in  the  inward  rotation  the  sub- 
scapulars is  also  relaxed.  This  method  is  also  applicable  to  old  cases, 
but  there  is  some  danger  of  fracture  of  the  humerus  in  the  outward 
rotation.  Anesthesia,  of  course,  most  effectively  relaxes  the  muscles, 
but  is  not  often  necessary  except  in  cases  of  long  standing. 

Associated  Injuries  and  Complications. — Associated  injuries  and  com- 
plications of  dislocation  of  the  shoulder,  in  addition  to  those  mentioned, 
may  occur  either  at  the  time  of  dislocation  or  during  reduction,  and  it  is 
often  difficult  to  say  at  which  time  a  given  complication  has  occurred. 
Fracture  of  the  anatomical  or  surgical  neck  is  rare,  and  is  indicated  by  the 
failure  of  the  head,  which  is  out  of  the  socket,  to  share  the  movements  of 
the  arm.  The  dislocated  and  fractured  fragment  may  sometimes  be 
reduced  by  direct  pressure  in  the  abducted  position.  Failing  in  this,  the 
following  plans  were  formerly  tried  :  (]  )  consolidation  of  the  fracture  and 
then  reduction;  (2)  prevention  of  union  and  the  fort  nation  of  a  false  joint ; 
('.',)  excision.  Open  incision  is  preferable,  and  Mclhirney  has  denion- 
>'•<!  the  ii  efulneSS,  in  accomplishing  reduction,  of  a,  stout  bent  hook 

introduced  into  a  hole  drilled  in  the  upper  fragment  in  such  cases,  espe- 
cially in  fractures  <>f  the  surgical   neck.    Fracture  of  the  neighboring 
■  >r  of  the  shaft  have  also  been  observed. 


182  TEE   UPPER  EXTREMITY 

Injury  to  the  nerves,  except  of  a  slight  and  transitory  nature,  are  not 
common;  they  occur  most  often  during  reduction  and  in  the  subglenoid 
variety  in  which  the  nerves  are  tightly  stretched  around  the  head.  The 
circumflex  nerve  (see  also  p.  174)  suffers  most  often,  and  has  been  entirely 
or  partly  ruptured,  stretched,  or  compressed.  The  main  nerve  trunks 
have  also  been  compressed  or  stretched. 

Serious  injury  to  the  bloodvessels  is  not  common,  and  it  is  often 
doubtful  whether  the  injury  occurred  during  the  dislocation  or  its  reduc- 
tion. The  axillary  vein  alone  has  been  ruptured  in  four  cases,  the  vein 
and  artery  in  three,  but  in  the  majority  the  axillary  artery  or  one  of  its 
branches  has  been  the  vessel  injured.1  In  some  of  the  latter  there  was 
complete  or  partial  rupture  of  all  of  the  coats  of  the  artery,  while  in  others 
the  coats  were  so  injured  that  rupture  or  the  formation  of  an  aneurysm 
followed  later.  The  rupture  is  usually  high  up,  where  the  head  pressed 
inward  upon  the  vessel,  and  in  some  cases  it  appeared  to  be  due  to  the 
tearing  off  of  a  branch,  the  subscapular  or  circumflex,  which  run  almost 
directly  outward,  where  they  are  fixed  to  the  tissues  among  which  they 
branch.  Again,  the  branches  just  named  have  also  been  torn  across  at  or 
near  their  origin,  in  which  case  the  radial  pulse  would  persist.  In  old  dis- 
locations the  vessels,  especially  the  outermost  one,  the  artery,  becoming 
adherent  to  the  bone  or  embedded  in  scar  tissue,  are  more  likely  to  be 
ruptured  in  reduction,  for  their  elasticity  is  diminished  and  the  strain 
comes  on  a  shorter  segment  of  the  vessel,  i.  e.,  the  segment  above  the 
adhesion  to  the  bone.  If  the  artery  is  atheromatous  the  danger  is  still 
greater. 

Fracture  of  the  Anatomical  Neck. — Fracture  of  the  anatomical  neck 
without  an  additional  line  of  fracture  through  the  tuberosities  is  a  rare 
and  obscure  form  of  injury,  and  occurs  most  often  in  connection  with 
dislocation  of  the  shoulder.  The  shortness  and  slight  degree  of  constric- 
tion of  the  neck  account  for  the  rare  occurrence  of  this  fracture.  When 
the  line  of  fracture  passes  through  the  tuberosities  the  outer  part  of  it  is 
extracapsular,  for  the  outer  part  of  the  capsule  is  attached  exactly  to  the 
anatomical  neck,  while  internally  it  is  attached  some  distance  below  it. 
From  the  latter  point  capsular  fibers  are  reflected  upward  to  the  lower 
margin  of  the  articular  head,  and  these  fibers  blend  with  the  periosteum 
and  usually,  but  not  always,  are  in  part  untorn  and  connect  the  head 
with  the  shaft  in  fracture  of  the  anatomical  neck.  When  the  head  has 
a  slight  vascular  connection  with  the  rest  of  the  bone,  and  perhaps  when 
it  has  none,  it  does  not  necessarily  necrose,  but  repair  is  possible,  being 
carried  on  largely  by  the  lower  fragment. 

The  symptoms  are  obscure.  Crepitus  may  be  absent,  owing  to  impaction 
or  the  ease  with  which  the  small  upper  fragment  within  the  socket  shares 
the  movement  of  the  lower  fragment.  The  lower  fragment  may  be 
displaced  upward  and  backward  by  the  action  of  the  deltoid  and  other 
muscles,  and  in  this  case  there  is  likely  to  be  slight  shortening  of  the  arm. 

1  Stimson,  Fractures  and  Dislocations,  fourth  ed.,  p.  453. 


THE  EXTERNAL  OR  DELTOID  REGION  is;; 

Again,  the  upper  end  of  the  lower  fragment  may  be  displaced  forward 
and  inward  by  the  muscles  attached  to  the  bicipital  ridges  and  groove. 
Up-and-down  movements  of  the  lower  fragment  may  be  unusually  free 
and  accompanied  by  pain  and  possibly  by  crepitus.  If  impaction  of  the 
fragments  occurs,  as  it  may  readih  do,  there  may  be  some  flattening  of 
the  deltoid. 

Separation  of  the  Upper  Epiphysis.— Separation  of  the  upper 
epiphysis  may  take  place  and  has  been  observed  at  any  time  from  birth  to 
the  age  of  nineteen,  when  the  upper  end  usually  joins  the  shaft.  The 
upper  epiphysis  comprises  the  head  and  tuberosities,  and  its  lower  border 
runs  upward  and  outward  along  the  lower  and  inner  half  of  the  anatomical 
neck  and  then  transversely  under  or  through  the  tuberosities  to  the  outer 
v(\^r,  where  it  lies  above  part  of  the  insertion  of  the  teres  minor.  The 
upper  end  of  the  shaft  is  shaped  like  a  low  cone,  the  height  of  the  cone 
increasing  with  age,  as  does  the  depth  of  the  corresponding  cup  in  the 
head.  Owing  to  this  shape,  the  nearly  transverse  direction  of  the  epi- 
physeal line,  and  the  width  of  the  humerus  at  this  level  complete  trans- 
verse displacement  of  the  fragments  does  not  often  occur,  especially 
as  the  periosteum  remains  untoru  to  some  extent,  particularly  posteriorly, 
and  where  it  is  torn  it  is  often  stripped  up  from  the  shaft  and  torn  below 
the  epiphyseal  line. 

Displacement. — The  upper  fragment  is  usually  abducted  and  rotated 
outward  by  the  muscles  attached  to  the  great  tuberosity,  while  the  shaft 
is  drawn  forward,  and  usually  inward,  by  the  muscles  inserted  into  the 
bicipital  ridges  and  groove.  The  anterior  edge  of  the  upper  end  of  the 
shaft  forms  a  distinct  forward  projection,  and  can  usually  be  plainly  felt 
2.5  cm.  il  in.)  or  more  below  the  acromion.  The  injury  may  occasionally 
cause  the  premature  ossification  of  the  conjugal  cartilage  and  the  con- 
sequent arrest  of  growth  of  the  arm,  for  the  greater  part  of  the  growth  in 
length  of  the  humerus  takes  place  at  its  upper  end — four-fifths  after  the 
tenth  year  (Yogt).  Hut  arrest  of  growth  has  been  reported  in  compara- 
tively few  cases.  It  is  much  more  likely  to  follow  an  inflammation  of 
the  cartilage  (epiphysitis). 

The  displacement  can  usually  be  reduced  by  direct  pressure  on  the 
projecting  fragment  combined  with  traction  on  the  arm,  preferably  in  the 

Completely  abducted  position,  as  the  upper  fragment  IS  already  abducted. 
The  forcible  raising  of  the  arm  beside  (he  head  often  throws  the  diaphysis 

backward  into  place,  as  the  posterior  part  of  the  capsule  prevents  the 

epiphysis  from  moving  farther  in  this  direction  (Moore).  In  a  few, 
especially  the  less  recent,  cases  open  incision  is  required. 

Fracture  of  the  Surgical  Neck.  The  fact  that  the  great  majority  of 
fractures  of  the  upper  end  of  the  humerus  occur  between  the  site  of  the 

epiphyseal  cartilage  and  the  insertion  of  the  pectoralis  and  teres  major 

muscles  ha-  given  the  name  "surgical  neck"  to  this  part  of  the  bone. 
A  fall  or  blow,  or  occasionally  muscular  action,  is  the  cuiise.     The  upper 

end  is  often  fixed  by  the  resistance  of  the  capsule,  the  ligaments,  and  per- 
haps the  muscles,  while  the  elbow  is  forced  or  fixed  in  a  forward  or  out- 
ward position  and  a  blow  is  received  on  the  outer  part  of  the  shoulder 


184  THE  UPPER  EXTREMITY 

so  that  a  "  cross-strain"  is  produced.  Fractures  of  the  lower  part  of  the 
neck  are  more  apt  to  be  oblique. 

The  displacement  is  commonly  as  follows:  The  upper  fragment  is 
abducted  and  rotated  outward  by  the  muscles  attached  to  the  great 
tuberosity,  while  the  lower  fragment  is  drawn  upward  by  the  deltoid, 
coracobrachialis,  and  triceps,  unless  the  fracture  is  transverse  or  impacted, 
and  its  upper  end  is  drawn  inward  by  the  muscles  attached  to  the  bicipital 
groove  and  ridges  and  by  the  continuation  of  the  fracturing  force.  When 
so  displaced  the  upper  end  of  the  lower  fragment  may  form  a  projection 
in  the  axilla,  and  the  elbow  may  be  so  abducted  as  to  alter  the  axis  of  the 
limb.  The  direction  of  this  axis  indicates  the  position  of  the  upper  end 
of  the  lower  fragment.  This  displacement  is  by  no  means  constant,  and  in 
the  majority  of  cases  it  is  too  slight  to  be  clinically  recognizable,  especially 
through  the  swollen  tissues.  In  such  cases  the  failure  of  the  tuberosities 
to  share  in  the  rotation  imparted  to  the  elbow  is  an  important  diagnostic 
sign.  I  have  had  one  case  where  the  sharp  upper  end  of  the  lower  frag- 
ment perforated  and  button-holed  the  deltoid  anteriorly,  and  required  an 
operation  to  dislodge  and  replace  it. 

Traction  in  the  abducted  position,  aided  by  pressure  on  the  lower 
fragment,  reduces  the  displacement.  In  adopting  a  suitable  dressing 
for  these  cases  the  action  of  the  muscles  mentioned  above  as  producing 
the  displacement  must  be  opposed,  which  may  be  partly  effected  by  using 
traction  by  means  of  weights  or  the  weight  of  the  arm.  In  some  cases  the 
partly  abducted  position  helps  to  maintain  reduction  of  the  displacement. 

Excision  of  the  Shoulder  Joint. — From  an  operative  point  of  view  the 
shoulder  joint  is  covered  only  by  the  skin  and  the  deltoid  muscle,  and 
hence  is  very  accessible.  It  is  most  desirable  for  the  subsequent  function 
of  the  arm  to  preserve  the  function  of  the  deltoid  by  sparing  its  nerve  (the 
circumflex),  which  reaches  it  from  behind,  hence  the  incision  should  be 
at  or  near  its  anterior  border.  With  this  object  in  view,  the  incision  begins 
at  the  edge  of  the  clavicle,  above  the  coracoid  process,  and  passes  down 
along  or  near  the  anterior  margin  of  the  deltoid.  The  pectoralis  major 
and  cephalic  vein  are  retracted  internally,  the  deltoid  externally,  and  if 
more  room  is  required  the  latter  may  be  detached  for  a  distance  from 
the  clavicle  without  disturbing  its  innervation.  The  acromial  branch  of 
the  acromiothoracic  artery  and  the  coraco-acromial  ligament  are  divided. 

The  capsule  is  opened  along  the  long  biceps  tendon,  and,  rotating  the 
bone  first  inward  and  then  outward,  the  great  and  then  the  lesser  tuber- 
osity is  cleared  of  muscular  attachments  by  vertical  incisions  close  to  the 
bone,  the  biceps  tendon  being  drawn  aside.  The  head  can  then  be  thrust 
up  through  the  slit  in  the  capsule  and  the  neck  cleared  and  divided. 

A  continuation  of  the  above  incision  for  excision  affords  one  of  the 
best  methods  (racket  method)  of  amputation  or  disarticulation  at  the  shoulder 
joint,  and  it  allows  an  excision  to  be  followed  by  an  amputation  if  the  case 
demands  it.  The  vertical  incision  is  carried  down  to  the  level  of  the 
axillary  fold  and  then  curved  outward  so  as  to  pass  horizontally  through 
the  lower  part  of  the  deltoid  and  around  the  posterior  and  inner  parts  of 
the  arm  and  then  turned  upward,  under  the  anterior  axillary  fold,  to  end 


PLATE  XIV 


LONG    TENDON 
OF    BICEPS 


CORACO-BRACHIALIS 

AND    SHORT    HEAD 

OF    BICEPS 


PEiT.orcy>U>tC  '  ; 


SECOND    RIB 
AXILLARY  ARTERY  WITH 

NERVES    OF    BRACHI 

AL    PLEXUS 


—  LONG    THORACIC 
NERVE 


FOURTH     PIB 


Horizontal  Section  through    the    Middle   of  the    Glenoid    Cavity. 

(Testut. ) 

The  arm  being  adducted,  Bhowing  the  axilla  on  transverse  section.      Etighi  side, 
upper  segmenl  of  Bed  ion. 


PLATE  XV 


FIG.  65 


BRACHIAL    PLEXUS 


ANTERIOR 
THORACIC 
AXILLARY  NERVE 

ARTERY 


CEPHALIC         ACROMIO- 
VEIN  THORACIC 

ARTERY 


Infraclavicular  Fossa  after  Removal  of  the  Fasciae. 
(Zuckerkandl.) 

The  pectoralis  muscle  is  separated  from  the  clavicle  and  turned  down. 


FIG.  67 


LONG    THORA- 
CIC   ARTERY 


INTERCOSTO- 
HUMERAL    NERVE 


BASILIC 
VEIN 
BRACHIAL    \/ 
ARTERY 


-LONG    THORACIC 
NERVE 


Axilla    from    Below    after    Removal    oT    Fasciae,   Connective 
ie,  and    Lymph    Nodes.     The    pectoralis    major  is  raised  u  i  >. 
kandl.) 


THE  AXILLA 


185 


in  the  vertical  incision.  In  the  vertical  incision  the  cephalic  vein  and 
branches  of  the  acromiothoracic  artery  are  ligated.  After  division  of 
the  lower  part  of  the  deltoid  this  muscle,  with  the  trunk  of  the  posterior 
circumflex  artery  and  the  circumflex  nerve,  can  be  readily  raised  from  the 
bone  by  blunt  dissection,  exposing  the  head,  around  which  the  capsule 
is  divided.  Then  the  muscular  tissues  on  the  inner  side,  with  the  vessels 
and  nerves  they  contain,  are  divided,  after  separating  them  from  the  bone 
from  above  downward  to  the  level  of  the  skin  incision.  In  this  step  the 
main  vessels  may  be  controlled  by  an  assistant  compressing  them  in  the 
inner  flap  between  the  thumb  and  fingers  of  both  hands,  or  they  may  be 
previously  ligated  through  the  skin  incision.  In  freeing  the  insertions  of 
the  teres  muscles  we  must  keep  close  to  the  bone  to  avoid  the  circumflex 
nerve,  which  passes  back  between  them  to  supply  the  deltoid,  the  chief 
muscle  of  the  stump. 

The  Axilla. 

This  pyramidal  space  between  the  chest  and  the  arm  may  be  regarded 
surgically  as  a  passageway  between  the  neck  and  the  upper  extremity  by 
which  tumors  or  abscesses  may  extend  from  the  one  to  the  other  region. 

Fig.  66 

PHRENIC 

NERVE 


EXT.   JUGULAR 
VEIN 


PECTORALIS 

MINOR 


CORACO- 

BRACHIALIS 


PECTORALIS 

MAJOR 


MEDIAN   NERVE 


■  ICCPS 

SHORT    HEAD' 


^'^STERNO- 
HYOID 


STERNO- 
MASTOID 


and  relation  •  <>  tnu  cle  ,     i  Kitei  Bardeleben.) 


Boundaries  Fig.64).  The  Anterior  Wall  (Figs.  65,  (iiii.  The.anterior 
wall  of  the  axilla  is  formed  by  the  pectoralis  major  with  its  sheath,  the 
pectoral  fascia,  and  the  pectoralis  minor  with  its  sheath,  the  clavipectoral 


186 


THE  UPPER  EXTREMITY 


fascia.  From  the  outer  border  of  the  pectoralis  minor,  where  the  two 
layers  of  its  sheath  reunite,  this  clavipectoral  fascia  extends  across  in 
front  of  the  axilla  as  a  triangular  sheet  to  become  continuous  with  the 
sheath  of  the  coracobrachialis.  The  lower  border  or  base  of  this  fascia 
is  connected  with  the  axillary  fascia  and  helps  to  hold  up  the  latter  and 
preserve  the  hollow  of  the  arm  pit. 

The  Posterior  Wall  (Figs.  67,  68). — The  posterior  wall  is  formed  by 
the  subscapularis,  latissimus  dorsi,  and  teres  major  muscles,  the  inner  wall 
(Fig.  68)  by  the  upper  four  ribs  and  spaces,  covered  by  the  serratus  magnus 
muscle.    The  outer  wall,  so  narrow  as  almost  to  deserve  the  name  angle,  is 

Fig.  68 
long  thoracic 

ARTERY 


PECTORALIS 
MAJOR  MUSCLE 


AXILLARY    VEIN 


MEDIAN    CUTA- 
NEOUS  NERVE 


POST.  THO 
RACIC    NERVE, 
DORSALIS 
SCAPUL/E  ART. 

SUBSCAPULAR 
NERVE 


LATISSIMUS 
DORSI    MUSCL 


SERRATUS   M; 

NUS    MUSCLE 


Lateral  chest  wall  (internal  axillary  wall)  and  posterior  axillary  wall,  with  their  muscles, 
vessels,  and  nerves.      (Merkel.) 


formed  by  the  humerus  covered  by  the  biceps  tendons  and  the  coraco- 
brachialis. The  apex  corresponds  to  the  first  intercostal  space  at  the 
commencement  of  the  axillary  vessels,  and  is  occupied  by  these  vessels, 
the  lymphatics,  and  the  brachial  plexus. 

The  Base. — The  base,  represented  by  the  hollow  of  the  arm  pit,  is  formed 
by  the  skin,  subcutaneous  tissue,  and  axillary  fascia,  which  extend  between 
the  anterior  and  posterior  borders  and  are  continuous  with  similar  struc- 
tures on  the  chest  wall  internally  and  the  arm  externally.  The  skin  of 
the  base  is  thin,  sensitive,  and  easily  chafed,  so  that  it  does  not  bear  the 
pressure  of  apparatus  well.    It  is  richly  provided  with  hairs,  sebaceous  and 


THE  AXILLA  IS? 

sweat  glands,  and  these  glands  or  the  hair  follicles  are  the  starting  point 
of  the  small  superficial  abscesses  often  met  with  here.  These  may  result 
in  secondary  glandular  abscesses,  but  they  tend  to  open  through  the  skin, 
being  separated  from  the  axilla  by  the  strong  axillary  fascia.  The  latter 
is  continuous  with  the  pectoral  and  clavipectoral  fascia  in  front,  the  fascia 
of  the  latissimus  dorsi  behind,  the  sheath  of  the  axillary  vessels  and  the 
deep  fascia  of  the  arm  externally,  and  that  of  the  thorax,  covering  the 
serratus  niagnus,  internally.  It  limits  the  downward  spread  of  an  axillary 
abscess  or  hematoma,  as  do  the  other  walls  of  the  axilla  the  extension  in 
their  direction.  Hence  after  filling  the  axilla,  and  thereby  bulging  the 
anterior  wall,  thrusting  back  the  scapula  and  obliterating  the  hollow 
of  the  armpit,  an  axillary  abscess  or  hematoma  may  pass  up  along  the 
vessels  into  the  supraclavicular  fossa  and  the  neck.  An  abscess  may 
occur  behind  the  pectoralis  major,  between  it  and  the  pectoralis  minor 
and  clavipectoral  fascia.  Such  an  abscess  would  be  separated  from 
the  axilla  by  the  strong  clavipectoral  fascia,  and  would  point  along  the 
lower  border  of  the  pectoralis  major,  or  possibly  in  the  sulcus  between 
it  and  the  deltoid. 

In  opening  an  axillary  abscess  the  incision  should  be  made  at  the  centre 
of  the  base  or  floor  of  the  axilla,  midway  between  the  anterior  and  poste- 
rior folds,  so  as  to  avoid  the  subscapular  vessels  along  the  lower  border  of 
the  subscapularis  and  the  long  thoracic  along  the  lower  border  of  the 
pectoralis  minor.  It  should  be  nearer  the  thoracic  or  inner  wall  than  the 
outer  to  avoid  the  axillary  vessels  in  the  latter  situation,  but  not  so  near 
the  inner  wall  or  so  deeply  plunged  internally  as  to  wound,  as  has  been 
done,  the  long  thoracic  nerve,  which  lies  on  and  supplies  the  serratus 
magnus.  An  occasional  branch  from  the  axillary  or  brachial  artery 
crossing  beneath  the  skin  of  the  axilla  to  the  breast,  in  place  of  or 
accessory  to  the  long  thoracic,  is  sometimes  found,  especially  in  female 
subjects,  and  might  be  injured  in  the  above  incision. 

The  Contents  of  the  Axilla.— The  contents  of  the  axilla  cm  prise  the 
axillary  vessels  and  their  branches,  together  with  nerves,  lymph  nodes,  and 
vessels,  areolar  tissue,  and  fat.  The  abundance  and  looseness  of  this 
fatty  areolar  tissue  allow  free  motion  of  the  arm,  but  also  favor  the 
collection  of  large  quantities  of  blood  or  pus. 

The  Axillary  Artery.  The  axillary  artery  keeps  to  the  outer  angle  or 
trail  of  the  axilla  in  all  positions  of  the  arm,  forming  a  curve  convex 
outward  and  upward,  when  the  arm  hangs  by  the  side,  and  a  straight 

line  from  a  little  external  to  the  middle  of  the  clavicle  to  the  groove  on  the 
inner  side  of  the  biceps,  when   the  arm   is  abducted    to  90  degrees  and 

rotated  outward. 

The  Axillary  Vein.  The  axillary  vein  lies  internal  to  and  somewhat 
below  the  artery.  If  overlaps  the  artery,  especially  during  expiration  and 
in  ii  upper  and  lower  parts,  being  more  separated  from  it  in  the  middle 
portion,  ;i->  it  takes  less  of  ;i  curve  than  the  artery.  When  the  arm  is 
abducted,  ;is  in  most  operations  upon  the  axilla,  the  vein  is  drawn  over 
the  artery  o  ■<  to  lie  almost  entirely  in  front  of  it  and  conceal  it.  The 
outer  vena  comes  of  the  brachial  artery  is  often  found  passing  over  the 


188  THE  UPPER  EXTREMITY 

lower  part  of  the  axillary  artery  to  join  the  vein  which  is  formed  by  the 
union  of  the  inner  vena  comes  and  the  basilic  vein.  This  union  usually 
occurs  near  the  lower  border  of  the  subscapularis,  but  sometimes  not  until 
just  below  the  clavicle,  a  condition  unfavorable  to  operations  on  the  artery, 
as  it  is  crossed  by  many  branches  which  unite  the  two  veins. 

A  muscular  slip  from  the  latissimus  dorsi  to  the  pectoralis  major  may  be 
found  crossing  the  inner  aspect  of  the  axillary  vessels  in  the  lower  part  of 
their  course.  This  may  be  mistaken  for  the  coracobrachialis  muscle, 
which  is  the  guide  to  the  lower  part  of  the  axillary  artery.  The  latter  part 
of  the  artery  is  superficial  and  easily  ligated,  remembering  that  the  vein 
lies  to  its  inner  side,  separated  from  it  by  the  internal  cutaneous  and 
ulnar  nerves,  while  the  musculocutaneous  nerve  is  external  and  the 
median  nerve  in  front  and  externally,  its  inner  root  crossing  in  front  of 
the  artery.  The  incision  for  ligation  of  the  artery  is  behind  the  anterior 
axilla  fold  in  line  with  that  vessel  (see  above),  which  lies  at  the  junction 
of  the  anterior  and  middle  thirds  of  the  axilla,  and  is  separated  from  the 
shoulder  joint  by  the  subscapular  muscle  and  its  tendon,  and  from  the 
humerus  by  the  coracobrachialis  and  the  tendons  of  the  biceps. 

The  axillary  vein  shows  the  respiratory  wave,  and  its  upper  part  is 
held  open  by  its  adhesion  to  the  costocoracoid  membrane.  Both  of 
these  facts  increase  the  liability  of  the  entrance  of  air  in  case  of  its  being 
wounded.  The  vein  is  more  often  wounded  than  the  artery,  as  it  is  larger, 
more  superficial,  and  overlies  it;  but  in  injuries  by  traction,  as  in  the 
reduction  of  a  dislocation,  the  artery  is  more  often  injured  than  the  vein. 
The  relative  frequency  of  aneurysm  of  the  axillary  artery  is  attributable  to 
its  nearness  to  the  heart,  its  abrupt  curve,  its  extensive  and  frequent 
movements,  and  its  liability  to  share  in  the  many  lesions  of  the  upper 
limb.  The  axillary  nerves  are  seldom  torn  by  traction  and  not  often 
injured  by  a  wound  in  the  axilla,  the  median  being  involved  most 
frequently,  the  musculospiral  least  frequently,  owing  to  their  relative 
depths. 

The  Axillary  Lymph  Nodes. — The  axillary  lymph  nodes  are  of  great 
surgical  importance,  especially  in  view  of  their  involvement  in  septic 
infection  of  the  upper  extremity  and  in  cancerous  growths  of  the  breast. 
They  comprise  four  or  more  fairly  distinct  groups:  (1)  The  axillary 
group  (3  to  4)  forms  a  chain  along  the  axillary  vein,  mostly  on  its  inner 
aspect,  and  receives  the  lymphatics  of  the  arm,  except  those  accompany- 
ing the  cephalic  vein;  (2)  the  pectoral  group  (4  to  5),  along  the  course  of 
the  long  thoracic  artery  and  the  outer  border  of  the  pectoralis  minor, 
beneath  the  lower  border  of  the  pectoralis  major  and  on  the  serratus 
magnus,  from  the  second  to  the  fourth  or  fifth  space,  receives  lymphatics 
from  the  mamma,  the  front  and  side  of  the  chest,  and  the  abdomen 
above  the  umbilicus;  (3)  the  subscapular  group  (6  or  more),  along  the 
subscapular  artery,  receives  lymphatics  from  the  back  of  the  shoulder, 
thorax,  and  neck;  (4)  the  deltopectoral  group  (If to  4),  along  the  cephalic 
vein  just  below  the  clavicle  on  the  costocoracoid  membrane,  between 
the  deltoid  and  great  pectoral  muscles,  receives  lymphatics  from' the 
outer  part  of   the  arm  and    the  deltoid   region;    (5)  the  subclavicular 


THE  AXILLA  ISO 

group  (6  to  12),  beneath  and  above  the  pectoralis  minor  and  along  the 
axillary  vessels  near  the  apex  of  the  axilla,  receives  the  efferents  of  the 
other  groups  either  directly  or  with  the  intervention  of  an  intermediate 
group  beneath  the  upper  end  of  the  long  thoracic  vein.  Most  of  their 
efferents  join  to  form  a  trunk  vessel  (subclavian),  which  passes  up  over 
the  vein  of  that  name  to  the  terminal  lymphatic  trunk.  One  or  more 
efferents  usually  enter  the  lower  deep  cervical  nodes  (supraclavicular). 
Of  these  groups,  the  most  important  are  the  first,  second,  and  fifth,  and 
especially  the  latter  two,  in  connection  with  cancer  of  the  breast.  As  they 
lie  along  the  inner  or  thoracic  wall  of  the  axilla,  it  is  this  wall  that  should  be 
palpated  to  determine  whether  there  is  lymphatic  involvement.  In  per- 
sons at  all  stout  it  is  difficult  or  impossible  to  palpate  nodes  only  slightly 
enlarged.  Belonging  to  the  second  group  are  one  or  two  nodes  at  the 
level  of  the  third  rib  which  are  usually  the  first  to  be  involved  in  cancer 
of  the  breast. 

As  a  free  communication  exists  not  only  between  the  nodes  of  each 
group,  but  between  the  different  groups,  infection  of  any  one  may  extend 
to  all  the  others.  Hence  in  removing  the  axillary  nodes  in  a  case  of  cancer 
of  the  breast  we  remove  not  the  pectoral  group  only,  but  all  the  groups  and 
the  fatty  and  areolar  tissue  which  contains  lymph  vessels.  As  the  axillary 
nodes  communicate  with  the  deep  cervical  nodes  in  the  supraclavicular 
fossa,  we  should  examine  these  in  advanced  cases  to  see  how  far  the  infec- 
tion has  spread.  Some  operators  regularly  remove  those  in  the  subclavian 
triangle  in  addition  to  those  in  the  axilla.  The  axillary  nodes  are  often 
infected  in  septic  wounds  of  the  areas  which  their  afferents  drain,  and  such 
infection  is  the  common  cause  of  axillary  abscess.  They  may  also  be 
involved  in  tuberculous  and  syphilitic  enlargement,  in  lymphosarcoma, 
and  in  other  conditions  accompanied  by  enlargement  of  the  lymph 
nodes. 

The  entire  axilla  up  to  its  apex  is  well  exposed  in  Ilalsted's  operation 
for  carcinoma  of  the  breast,  in  which  the  sternal  portion  of  the  great 
pectoral  is  removed,  its  clavicular  portion  incised  vertically,  and  the 
pectoralis  minor  divided  or  removed,  thus  removing  or  laying  open  the 
anterior  axillary  wall.  The  entire  cellulo-adipose  contents  of  the  axilla, 
in  which  the  lymph  vessels  and  nodes  are  embedded,  and  the  veins 
which  they  usually  accompany  are  entirely  removed  in  one  mass.  The 
dissection  is  best  begun  along  the  axillary  vein,  which  is  cleared  of  its 
surrounding  lymph-bearing  tissue  after  doubly  ligating  and  dividing  its 
many  tributaries.  The  nodes  when  diseased  are  often  adherent  to  the 
axillary  vessels,  especially  the  vein,  and  their  pressure  on  the  latter 
causes  the  edema  of  the  arm  often  observed  in  advanced  cases.  When 
necessary  to  complete  ;i  radical  operation  the  vein  may  be  removed 
with  the  nodes,  and  this  not  only  entails  no  danger  to  the  vitality  of  the 
arm  but  often  gives  rise  to  no  permanent  swelling  of  the  extremity. 

Although   in  inflammatory  or  other  affections  of  the  arm   the  axillary 

(group  of  nodes  i-  usually  enlarged  mid  painful  and  often  breaks  down 
into  an  abscess  so  as  to  require  removal  or  incision,  yet,  in  several  cases 
of  pro fon ml  sepsis  of  the  arm,  ending  Fatally  after  a  time,  I  have  found  no 


190  THE  UPPER  EXTREMITY 

swelling:  or  tenderness  of  the  nodes  in  the  axilla.  But  whether  this  was 
due  to  an  imperfection  of  the  nodes  or  to  the  nature  of  the  infection  I  am 
unable  to  say.  At  least,  having  observed  a  similar  condition  in  the  lower 
extremity  in  two  fatal  cases,  I  consider  the  prognosis  bad  when  the  nodes 
of  the  axilla  or  groin  are  not  enlarged. 


THE  REGION  OF  THE  ARM  OR  UPPER  ARM. 

This  extends  from  the  lower  limit  of  the  "shoulder,"  the  insertion  of  the 
pectoralis  major  internally  and  the  deltoid  externally,  to  the  upper  limit 
of  the  region  of  the  elbow,  two  or  three  fingers'  breadths  above  the 
condyles. 

Surface  Markings  and  Landmarks. — Whereas  in  women,  infants, 
and  fat  subjects  the  arm  is  regularly  rounded,  in  muscular  subjects  it  is 
flattened  on  each  side  and  especially  prominent  in  front,  owing  to  the 
distinctly  outlined  biceps  muscle.  On  either  side  of  the  latter  is  a  groove, 
of  which  the  inner  is  much  the  more  marked  and  runs  from  the  axilla 
to  the  bend  of  the  elbow.  It  indicates  the  position  of  the  basilic  vein 
and  the  brachial  artery,  the  course  of  the  latter,  in  the  extended  and  supi- 
nated  arm,  corresponding  to  a  line  drawn  along  the  inner  border  of  the 
biceps,  from  beneath  the  anterior  axillary  fold  to  the  middle  of  the  bend 
of  the  elbow.  The  artery  is  superficial  and  can  be  felt  throughout  its  entire 
length.  The  outer  shallower  groove  extends  up  to  the  deltoid  insertion 
and  indicates  the  positibn  of  the  cephalic  vein,  which  above  the  deltoid 
insertion  runs  upward  and  inward  along  the  anterior  border  of  that 
muscle  and  then  in  the  groove  between  it  and  the  pectoralis  major.  The 
deltoid  insertion  is  easily  made  out  and  is  an  important  landmark,  indi- 
cating the  middle  of  the  humeral  shaft  and  the  level  of  the  insertion  of 
the  coracobrachialis,  of  the  upper  limit  of  the  brachialis  anticus,  of  the 
entrance  of  the  nutrient  artery  on  the  inner  surface,  and  of  the  point  where 
the  musculospiral  nerve  and  superior  profunda  artery  reach  the  outer 
border  of  the  bone.  The  shaft  of  the  humerus  is  so  well  covered  by  muscles 
that  it  can  only  be  felt  below  the  deltoid  insertion,  from  whence  the 
outer  border  can  be  traced  down  into  the  external  supracondylar  ridge. 

Superficial  Topography. — The  course  of  the  median  nerve  corresponds 
to  that  of  the  artery,  lying  external  to  it  in  the  upper  third,  in  front  in  the 
middle  third,  and  internal  in  the  lower  third.  The  internal  profunda 
artery  is  represented  by  a  line  from  the  inner  aspect  of  the  brachial  artery 
at  the  middle  of  the  shaft  to  the  back  part  of  the  internal  condyle.  The 
ulnar  nerve,  following  the  brachial  artery  on  its  inner  side,  diverges  from 
it  at  the  middle  of  the  shaft,  with  the  inferior  profunda  artery,  and  follows 
a  line  from  this  point  to  the  gap  between  the  olecranon  and  the  internal 
condyle.  It  may  be  felt  along  the  back  of  the  internal  supracondylar 
ridge.  The  musculospiral  nerve,  with  the  superior  profunda  artery, 
follows  a  line  from  just  below  the  junction  of  the  posterior  fold  of  the 
axilla  with  the  arm  downward,  backward,  and  outward  to  the  outer  border 
of  the  humerus  at  the  deltoid  insertion,  and  thence  downward  to  the  front 


THE  REGION  OF   THE  ARM   OR  UPPER  ARM  \\\\ 

of  the  external  condyle,  lying  between  the  brachioradialis  and  the  bra- 
chialis  anticus  in  the  lower  fourth  of  the  arm.  The  lower  end  of  the 
groove  external  to  the  biceps  corresponds  to  the  superficial  portion  of  the 
musculocutaneous  nerve.  The  anastomotica  magna  is  given  off  about 
.">  em.  {2  in.)  above  the  bend  of  the  elbow. 

The  Skin. — The  skin  of  the  arm  is  smooth  and  thin,  especially  anteriorly 
and  laterally,  where  it  is  very  free  from  hairs,  so  that  it  is  here  very  suit- 
able for  skin  flaps  and  for  skin  grafting.  The  point  of  insertion  of  the 
deltoid  is  free  from  muscular  movement,  so  that  the  overlying  skin  is  very 
well  situated  for  vaccination,  as  it  was  formerly  for  the  application  of 
a  seton.  The  skin  is  so  loosely  attached  by  the  subcutaneous  tissues  to 
the  deep  fascia  that  in  circular  amputation  it  can  be  sufficiently  drawn  up 
by  the  traction  of  the  hand,  and  requires  no  separate  dissection  to  form  a 
flap.  If  it  requires  any  separation  with  the  knife,  it  is  only  along  the  lines 
of  the  intermuscular  septa.  It  is  more  loosely  attached  on  the  inner  than 
on  the  outer  aspect  of  the  arm  (i.  e.,  over  the  deltoid).  The  skin  is  readily 
stripped  up  in  contused  and  lacerated  wounds. 

The  Deep  Fascia  [brachial  aponeurosis). — The  deep  fascia  completely 
invests  the  underlying  muscles  to  which  it  is  loosely  attached.  It  is 
continuous  with  that  covering  the  elbow  region  below  and  with  the  fascia 
of  the  deltoid,  the  axilla,  and  the  anterior  and  posterior  axillary  walls 
above.  It  is  thin  in  front,  where  it  covers  the  biceps,  thicker  behind.  At 
the  sides  it  is  connected  by  the  internal  and  external  intermuscular  septa 
with  the  internal  and  external  borders  of  the  bone.  The  external  inter- 
muscular septum,  the  weaker  of  the  two,  extends  from  the  external  con- 
dyle to  the  deltoid  insertion,  and  is  perforated  by  the  musculospiral  nerve 
and  superior  profunda  artery  about  midway  between  the  deltoid  insertion 
and  the  tip  of  the  external  condyle.  The  internal  intermuscular  septum 
extends  from  the  internal  condyle  to  the  teres  major  muscle  (internal 
bicipital  ridge),  and  is  perforated  by  the  ulnar  nerve  and  the  inferior 
profunda  artery  about  5  cm.  (2  in.)  above  the  internal  condyle. 

These  two  septa  with  the  deep  fascia  divide  the  arm  into  two  compart- 
menis,  of  which  the  posterior  contains  the  triceps  muscle  with  the  upper 
part  of  the  musculospiral  and  the  lower  brachial  portion  of  the  ulnar 
nerves  and  their  accompanying  vessels;  the  anterior  contains  the  rest  of 
the  brachial  muscles  and  soft  parts.  These  compartments  confine  to  a 
certain  extent  inflammatory  or  hemorrhagic  effusions,  which,  however, 
can  pass  from  one  to  the  other  by  following  the  structures  that  pierce  the 
septa.  The  brachial  aponeurosis  itself  is  pierced  along  the  groove  internal 
to  the  biceps  by  the  internal  cutaneous  nerve  about  the  middle  and  by 
the  basilic   vein   a   little   below    the   middle  of    the   arm,   and   along    the 

•  rnal   bicipital    groove  by  the  external  cutaneous   nerve,  just  above 

the  elbow. 

The  Brachial  Artery.     The  brachial  artery  may  be  ligated  in  any  pari  of 
it-  course.      The  best  guide  is  the  inner  border  of  the  biceps,  which  may 
lap  it  in  muscular  subjects.     Its  changing  relations  ivitb  the  median 
m re,    •(■(■  above)  should  be  remembered,  but  these  are  not  always  con- 
stant, -'■  thai  ihi-  nerve  is  a  poor  guide.    The  number  of  cross-branches 


192  THE  UPPER  EXTREMITY 

between  the  two  vense  comites  sometimes  embarrasses  the  operator.  The 
ulnar  nerve  lies  close  to  the  inner  side  in  its  upper  half,  and  may  be  mis- 
taken for  the  median  if  the  incision  is  too  far  internal.  The  musculo- 
spiral  nerve  is  also  behind  the  upper  end  of  the  vessel. 

Anomalies  occur  more  often  in  the  brachial  than  in  almost  any  other 
artery.  The  most  important  anomaly  from  a  surgical  standpoint  is  its 
high  division  (even  in  the  axilla),  in  which  case  the  smaller  branch  lies 
in  front  of  and  the  other  behind  the  median  nerve.  Hence  if  an  artery  is 
found  in  front  of  the  nerve  we  should  look  for  another  behind  it.  Again, 
in  the  lower  part  of  the  arm  the  artery  or  one  of  its  branches  may  deviate 
internally  to  pass  to  the  inner  side  of  the  supracondylar  process,  with 
the  median  nerve.  Behind  the  artery  lies  the  coracobrachialis  for  a  short 
distance,  lower  down  the  brachialis  anticus.  The  artery  lies  internal  to 
the  humerus  in  its  upper  half  or  more,  in  front  of  it  below;  so  that  it  may 
be  compressed  against  the  bone  by  pressure  outward  and  slightly  backward 
above,  and  directly  backward  below.  Unless  this  pressure  is  applied 
carefully  by  the  fingers,  the  median  nerve  can  hardly  avoid  pressure,  the 
result  of  which  is  the  pain  often  complained  of  after  the  application  of  a 
tourniquet. 

The  Lymph  Vessels. — The  lymph  vessels  are  largely  superficial.  Most 
of  these  (15  to  18)  accompany  the  basilic  vein,  where  they  can  readily 
be  seen  as  a  band  of  red  striae  in  lymphangitis.  The  most  external  stem 
usually  accompanies  the  cephalic  vein. 

The  Musculospiral  Nerve. — The  musculospiral  nerve  in  its  passage  along 
the  musculospiral  groove  is  in  close  contact  with  the  bone,  and  hence  may 
be  injured  in  contusions  and  wounds,  and  especially  in  fractures  of  the 
humeral  shaft.  It  may  also  escape  injury  at  the  time  of  fracture,  to  be 
subsequently  involved  and  compressed  in  the  callus.  In  many  cases  an 
operation  has  become  necessary  to  free  it  from  the  canal  of  callus  or  bone 
in  which  it  is  compressed.  It  has  also  been  paralyzed  by  the  pressure  of 
the  head  resting  upon  the  supinated  and  abducted  arm  in  sleep.  In  the 
upper  part,  on  the  inner  aspect  of  the  arm,  it  is  the  nerve  which  most 
often  suffers  from  crutch  paralysis,  the  ulnar  coming  next  in  frequency. 
In  all  such  cases  there  is  pain  and  hyperesthesia  along  the  course  of  the 
nerve  and  its  branches  if  the  nerve  is  merely  irritated;  paralysis  and  anes- 
thesia if  it  is  divided  or  severely  compressed  or  stretched.  The  symptoms 
of  paralysis  resemble  those  in  lead  palsy,  which  also  affects  this  nerve. 
The  extensors  of  the  wrist  and  fingers  are  paralyzed  and  "wrist-drop"  is 
produced,  indicating  the  inability  of  the  extensors  to  extend  the  wrist. 
Owing  to  the  above  conditions  the  musculospiral  is  more  often  paralyzed 
than  any  other  branch  of  the  brachial  plexus. 

The  nerve  is  most  conveniently  exposed  after  it  has  pierced  the  inter- 
muscular septum  by  an  incision  following  the  anterior  border  of  the 
brachioradialis,  whose  centre  is  opposite  the  point  of  perforation  of  the 
septum  or  midway  between  the  deltoid  insertion  and  the  external  con- 
dyle. It  is  sought  for  as  it  enters  the  cleft  between  the  brachioradialis 
and  the  brachialis  anticus.  If  it  is  to  be  exposed  on  account  of  injury 
in  the  musculospiral  groove,  the  incision  is  carried  upward  along  the 
posterior  margin  of  the  deltoid  insertion. 


PLATE   XVI 

FIG.  69 


CEPHALIC 
VEIN 


BRACHIALIS 

MUSCLE  BICEPS 


MUSCULO-SPIRAL 
NERVE 


MUSCULO-CUTA- 


BRACHI AL 
APONEUROSIS 


EXT.    INTERMUS- 
CULAR   SEPTUM 


TRICEPS 
MUSCLE 


ULNAR    NERVE 


INT.    INTERMUS- 
CULAR   SEPTUM 


Cross-section  through  the  Middle  of  the  Right  Arm  of  a  Female. 
Upper  segment  viewed  from  below.     (Tillaux.) 


FIG.  70 


CEPHALIC 
VEIN 


EXTERNAL 
CUTANEOUS 
NERVE    AND 
IE0IAN    VEIN 


NTERNAL 
CUTANEOUS 
NERVE 


BRACHIAL 

ARTERY 


BASILIC 
VEIN 


MEDIAN 
NERVE 


MEDIAN 
BASILIC 
VEIN 


.'    Right  Elijow.     Superficial  view.     (Joessel  ) 


THE  REGION  OF   THE  ARM  OR   UPPER  ARM  193 

Fracture  of  the  Shaft  of  the  Humerus. — Fracture  of  the  shaft  of  the 
humerus,  or  that  part  between  the  insertion  of  the  pectoralis  major  and 
the  upper  part  of  the  supracondylar  ridges,  is  most  often  due  to  direct 
violence,  sometimes  to  indirect  violence.  It  is  more  often  broken  by 
muscular  action,  such  as  throwing  a  stone  or  the  trial  of  strength  known 
as  "wrist  turning,"  than  any  other  bone  in  the  body.  The  displacement 
is  usually  inconsiderable  and  depends  largely  upon  the  fracturing  force 
and  the  line  of  fracture.  Secondarily  the  muscles  attached  to  the  two 
fragments  may  have  some  effect  upon  their  relative  position.  Thus  the 
lower  fragment  is  often  drawn  up  by  the  biceps  and  triceps  muscles,  but 
the  weight  of  the  arm  resists  any  considerable  shortening.  Theoretically 
in  fractures  above  or  below  the  deltoid  insertion  the  lower  or  upper 
fragments  respectively  would  be  drawn  outward  by  the  action  of  the 
deltoid,  but  practically  the  displacement  is  usually  independent  of  this 
action. 

Delayed  Union  and  Non-union. — Delayed  union  and  non-union  are  of 
much  more  frequent  occurrence  in  the  humerus  than  in  any  other  bone. 
Among  the  causes  that  lead  to  this  may  be  mentioned  (1)  the  inter- 
position between  the  fragments  of  muscular  tissue  with  which  the  bone 
is  almost  completely  surrounded,  the  two  fragments  being  driven  into 
muscular  masses  on  opposite  sides  of  the  bone;  (2)  the  defective  immo- 
bilization  of  the  fragments  due  largely  to  the  imperfect  fixation  of  the 
joints  above  and  below.  According  to  Hamilton  the  flexed  elbow  soon 
becomes  stiff  by  reason  of  muscular  rigidity,  so  that  the  movement  of 
the  forearm  imparts  a  movement  to  the  upper  end  of  the  lower  fragment 
instead  of  flexion  or  extension  of  the  elbow.  But  this  alone  cannot 
account  for  the  condition,  for  it  would  cause  a  greater  movement  of 
the  fragments  of  fractures  high  up  in  the  shaft,  and  non-union  is  more 
common  in  the  middle  third. 

Amputation  of  the  Arm. — ///  the  lower  half  the  circular  amputation  is 
best.  The  division  and  retraction  of  the  skin  has  been  already  referred 
to.  As  only  the  biceps  has  no  attachment  to  the  bone,  it  redacts  most 
and  requires  separate  division  a  thumb's  breadth  below  where  the  other 
muscles  are  divided,  at  the  edge  of  the  retracted  skin.  After  division  of 
the  muscles  and  continued  retraction  of  the  soft  parts  the  fleshy  cone  may 
again  be  divided  at  its  base,  at  the  level  of  the  fully  retracted  skin. 

Above  the  middle  of  the  arm  the  biceps,  long  head  of  the  triceps,  deltoid, 
and  coracobrachialis  may  all  retract  considerably  and  unequally,  hence 
amputation  by  long  anterior  and  shorter  (one-half  of  a  nlerior)  posterior 
flaps  has  some  advantages.  The  brachial  artery  should  be  in  the  pos- 
terior flap.     The  principal  arteries  cut  are  the  brachial  (with  the  median 

nerve  ,  the  superior  profunda  on  the  postero-external  aspect  (with  the 
musculospiral  nerve),  and,  in  the  lower  half  of  the  arm,  the  inferior  pro- 
funda on  the  inner  aspect  (with  the  ulnar  nerve).  I  Fig.  69.)  In  the  flap 
method  all  the  principal  arteries  divided  are  in  the  posterior  flap.     In  the 

circular  method  the  free  retraction  of  the  muscles  and  the  active  growth 
of  die  upper  epiphysis  before  its  union  with  theshaftai  theageof  nine- 
teen   p.  is:;    j    ap(  to  result  in  a  "conical  stump." 
13 


194  THE  UPPER  EXTREMITY 

To  reach  the  humerus  for  removal  of  sequestra,  etc.,  incision  along  the 
outer  border  is  preferable,  for  the  museulospiral  nerve  is  the  only  struc- 
ture which  need  be  avoided. 


THE  REGION  OF  THE  ELBOW. 

The  limits  of  this  region  may  be  arbitrarily  assigned  as  two  or  three 
fingers'  breadth  above  and  below  the  "fold  of  the  elbow."  The  elbow 
is  flattened  from  before  backward. 

Surface  Markings  and  Landmarks  (Fig.  70). — In  front  are  visible 
three  muscular  elevations,  one  on  the  outer  side  corresponding  to  the 
brachioradialis  and  the  extensor  group,  one  on  the  inner  side  corre- 
sponding to  the  pronator  radii  teres  and  the  flexor  group,  and  one  in 
the  centre  corresponding  to  the  biceps  and  brachialis.  The  two  lateral 
elevations  converge  and  meet  below,  enclosing  between  them  a  depres- 
sion, the  cubital  fossa,  into  which  the  biceps  tendon  is  felt  to  sink  toward 
its  insertion.  From  this  fossa  two  grooves  forming  a  V  are  continued 
upward  along  the  two  sides  of  the  biceps  tendon,  to  become  continuous 
with  the  bicipital  grooves  of  the  arm.  The  details  are  distinct  only  in 
thin  or  muscular  subjects.  The  biceps  tendon  is  plainly  felt,  especially 
along  its  outer  border,  the  inner  border  being  continuous  with  the 
bicipital  fascia.  The  "fold  of  the  elbow"  is  a  crease  in  the  skin  of  the 
front  of  the  elbow  extending  transversely  between  the  two  condyles,  with 
a  slight  convexity  downward.  Hence  it  is  some  little  way,  2  to  4  cm. 
(f  to  1^  in.),  above  the  joint  line.  It  is  obliterated  in  extension  and  not 
constant  in  position,  so  that  it  is  not  of  great  service  as  a  landmark.  It 
may  be  of  some  use,  as  employed  by  Malgaigne,  to  diagnosticate  between 
an  ordinary  dislocation  of  the  elbow  and  a  supracondylar  fracture  of  the 
humerus,  the  lower  end  of  the  humerus  projecting  below  this  fold  in 
the  former  and  the  lower  end  of  the  upper  fragment  forming  a  promi- 
nence above  it  in  the  latter. 

The  two  condyles  are  plainly  felt,  the  inner  and  more  prominent  one 
even  in  conditions  of  extreme  swelling.  The  outer  condyle  may  be 
readily  seen  in  semiflexion.  The  inner  condyle  points  more  or  less  back- 
ward. About  2  cm.  (-§-  in.)  below  the  more  rounded  external  condyle  the 
rounded  head  of  the  radius  can  be  felt,  especially  on  rotating  the  forearm. 
In  extension  of  the  elbow  a  marked  depression  on  its  posterior  aspect  indi- 
cates the  position  of  the  head  of  the  radius  and  corresponds  to  the  interval 
between  the  brachioradialis  and  the  anconeus  muscles.  The  two  humeral 
condyles  are  in  the  same  transverse  line  with  one  another  and,  when  the 
arm  is  fully  extended,  with  the  uppermost  part  of  the  plainly  felt  olecranon 
process.  When  the  elbow  is  flexed  the  tip  of  the  olecranon  comes  to  lie 
below  the  intercondylar  line,  so  that  when  it  is  flexed  to  a  right  angle 
the  interval  is  a  little  more  than  2.5  cm.  (1  in.).  The  intercondylar  line 
is  at  right  angles  to  the  axis  of  the  humerus.  These  relations  are  of  great 
importance  in  differentiating  dislocation  from  supracondyloid  fracture, 
for  in  the  latter  case  they  are  preserved,  in  the  former  they  are  altered. 


THE  REGION  OF   THE  ELBOW  195 

Furthermore,  in  full  extension  the  point  of  the  olecranon  is  nearly  in  the 
same  transverse  vertical  plane  with  the  two  condyles,  while  in  dislocation 
it  is  displaced  backward.  The  olecranon  does  not  lie  midway  between  the 
two  condyles,  but  nearer  the  internal  condyle,  by  12  to  15  mm.  {h  in.),  so 
that  the  groove  between  the  olecranon  and  the  inner  condyle  is  narrower 
as  well  as  deeper  than  that  between  the  olecranon  and  the  outer  condyle. 
Neither  the  coronoid  process  of  the  ulna  nor  the  radial  tubercle  of  the 
radius  can  be  distinctly  felt  under  ordinary  conditions. 

Topography. — The  joint  line  of  the  elbow  is  only  about  two-thirds, 
4  cm.  (1^  in.),  of  the  width  between  the  condyles,  and,  while  it  nearly 
corresponds  externally  with  the  lateral  limit  of  the  condyle,  its  inner 
end  is  some  distance,  nearly  2  cm.  (f  in.),  external  to  the  internal  con- 
dyle This  partly  accounts  for  the  prominence  of  the  internal  condyle. 
The  line  of  the  humeroradial  joint  is  horizontal  and  can  be  felt  between  the 
head  of  the  radius  and  the  external  condyle;  that  of  the  humero-ulnar 
joint  slopes  obliquely  downward  and  inward,  so  that  the  inner  end  of 
the  trochlea  is  1  cm.  (f  in.)  below  the  outer  end.  The  obliquity  of  the 
humero-ulnar  joint  makes  the  axis  of  the  extended  forearm  to  diverge 
outward  at  an  angle  of  6  degrees,  providing  for  the  "carrying  function" 
of  the  arm.  It  also  makes  the  hand  to  be  carried  up  toward  the  face  in 
flexion,  unless  the  forearm  is  supinated. 

The  Ulnar  Nerve. — The  ulnar  nerve,  lying  in  the  deep  and  narrow 
depression  between  the  olecranon  and  the  internal  condyle,  is  exposed  to 
injury  by  pressure  against  its  hard  bed.  Pressure  on  it  gives  the  peculiar 
numbness  and  tingling  of  the  ulnar  side  of  the  hand,  etc.,  which  is  known 
as  hitting  the  "funny  bone."  It  was  wittily  remarked  that  it  was  so 
named  because  it  bordered  on  the  humerus.  As  the  result  of  trauma  or  of 
congenital  conditions  the  nerve  may  come  to  lie  in  front  of  the  internal 
condyle  or  slip  in  front  on  flexion  of  the  elbow.  The  congenital  or  idio- 
pathic cases  are  far  more  numerous  and  seldom  give  rise  to  symptoms 
sufficient  to  require  operation.  The  ulnar  nerve  is  not  confined  to  its 
groove  in  from  20  to  25  per  cent,  of  cases.  It  is  particularly  important 
to  avoid  it  in  excision  of  the  elbow  by  keeping  close  to  the  bone  in  its 
neighborhood.  In  a  case  of  ankylosis  of  the  elbow  with  much  overgrowth 
of  bone,  due  to  a  bad  fracture,  I  have  found  the  nerve  in  a  bony  canal. 

The  in  11. sen  I  o.\//iral  nerve  divides  into  the  radial  and  posterior  inter- 
0  eous  nerves  just  above  and  in  front  of  the  capitellum  and  may  be 
injured  in  dislocations  of  the  1 1*  :i « J  of  the  radius. 

The  Brachial  Artery.  The  brachial  artery  lies  in  the  inner  of  the  two 
grooves  in  front  of  the  elbow,  just  internal  to  the  pearly  white  biceps 
tendon,  which  is  an  excellent  guide  to  it,  and  rather  more  external  to  the 

median  nerve.  It  passes  under  the  bicipital  fascia,  where  it  bifurcates 
about  l_'  niui.  (\  in. j  below  the  centre  of  the  bend  of  the  elbow.  It  may 
be  en, a  pressed  by  forcible  flexion  of  the  joint  so  as  to  diminish  or  even  .stop 
the  radial  pulse.  Accordingly  aneurysms  here,  more  frequent  in  blood- 
letting days,  have  been  treated  by  compression,  by  flexion  of  the  elbow. 
In  the  fully  extended  position  the  artery  is  somewhat  flattened  beneath  the 
bicipital  fa  cia    <>  0    to  le  sen  the  radial  pulse,  or  even  to  stop  it  in  the 


196  THE   UPPER  EXTREMITY 

hyperextension  possible  with  fracture  of  the  olecranon  or  dislocation  of 
the  elbow.  It  has  been  ruptured  by  the  forcible  straightening  of  a  stiff, 
bent  elbow. 

The  Median  Vein. — The  median  vein  is  joined  by  the  deep  median  vein, 
thus  receiving  the  blood  of  the  deep  veins  of  the  forearm,  and  divides  into 
the  median  basilic  and  median  cephalic  in  the  depression  at  the  apex 
of  the  V  {cubital  fossa).  The  median  basilic  vein  crossing  superficial  to 
the  biceps  tendon  and  fascia  comes  to  lie  in  the  inner  groove  where  it 
joins  the  posterior  ulnar  vein  a  little  above  the  internal  condyle,  forming 
thereby  the  basilic  vein.  Similarly  the  median  cephalic,  passing  up  in  the 
outer  groove,  forms  the  cephalic  vein  by  joining  the  radial  vein  about 
the  level  of  the  external  condyle. 

An  M-shaped  figure  is  thus  formed  by  the  veins  in  front  of  the  elbow, 
but  this  typical  arrangement  is  by  no  means  constant,  occurring  only  in 
about  50  per  cent,  of  cases.  But  in  almost  all  cases  a  communicating 
vein  crosses  the  biceps  tendon  and  fascia  obliquely,  and  therefore  over- 
lies the  brachial  artery  and  median  nerve,  and  this  vein  is  usually  large 
enough  for  venesection  or  intravenous  infusion. 

The  median  basilic  vein  or  its  substitute  may  cross  the  artery  trans- 
versely or  obliquely  or  it  may  run  nearly  parallel  with  it,  in  front  of  it, 
or  to  one  side.  Of  all  the  veins  in  front  of  the  elbow,  the  median  basilic 
is  usually  the  largest,  the  most  prominent,  the  nearest  the  surface,  and  the 
one  least  subject  to  variation.  Hence  it  was  the  one  most  often  chosen 
for  venesection  in  bloodletting  days,  and  now  is  often  chosen  for  intra- 
venous infusion,  in  spite  of  the  fact  that  it  is  separated  from  the  artery 
beneath  by  the  bicipital  fascia  only.  This  membrane,  whose  density 
depends  upon  the  muscular  development,  is  an  excellent  protection  to 
the  artery,  but  on  account  of  the  blind  method  of  venesection  formerly 
employed  it  is  not  strange  that  the  artery  was  often  wounded  with  the 
vein,  giving  rise  to  an  arteriovenous  aneurysm,  an  aneurysmal  varix  if 
the  communication  is  direct,  a  varicose  aneurysm  if  there  is  an  inter- 
vening sac.  The  latter  forms  were  more  common  at  the  elbow  than 
anywhere  else.  The  median  cephalic  is,  therefore,  safer,  but  with  open 
exposure  of  the  vein,  as  for  intravenous  infusion,  it  seems  scarcely 
possible  to  wound  the  artery. 

Of  the  cutaneous  nerves  at  the  elbow  the  external  cutaneous  passes 
behind  the  median  cephalic  vein,  the  anterior  division  of  the  internal 
cutaneous  passes  behind  cr  (less  frequently)  in  front  of  the  median  basilic. 
Hence  the  latter  nerve  or  its  branches  may  be  wounded  in  opening  the 
median  basilic  vein,  an  injury  that,  according  to  Tillaux,  may  lead  to 
intense  and  chronic  neuritis.  Small  twigs  of  the  external  cutaneous  nerve 
may  cross  in  front  of  the  median  cephalic  vein,  and  the  injury  to  these 
branches,  or  possibly  the  main  nerve  behind  the  vein,  or  their  inclusion 
in  the  scar  may  lead,  according  to  Mr.  Hilton,  to  a  reflex  contraction  of  the 
elbow,  "bent  arm/'  due  to  the  contraction  of  the  biceps  and  brachialis 
muscles  which  are  supplied  by  its  main  trunk,  the  musculocutaneous. 
He  has  cured  the  condition  by  resection  of  the  scar,  which  was  found  to 
have  included  some  of  the  nerve  filaments. 


PLATE  XVII 


FIG.  71 


Left  Elbow.     Anteroposterior'.      Arm  extended  and  supinated. 
Male,  aged   thirty  years. 


THE  REGION  OF   THE  ELBOW  1<)7 

The  .superficial  lymphatics  accompany  the  veins,  lying  in  front  of  them, 
and  are  most  numerous  on  the  antero-internal  aspect  of  the  elbow. 
Situated  in  front  of  the  upper  part  of  the  internal  condyle  is  the  epi- 
trochlear  lymph  group  (1  to  4  in  number).  The  lowest  node  is  the  most 
constant,  is  termed  the  epitrochlear  node,  and  is  the  lowest  node  in  the 
upper  limb.  It  may  become  inflamed  in  any  injury  or  inflammation  of 
the  hand  and  forearm,  especially  of  its  ulnar  side,  from  whence  its  afferent 
vessels  come.  It  is  not  infrequently  enlarged  and  palpable  in  the  early 
adenopathy  of  syphilis.  xVround  the  elbow-joint  is  an  extensive  and  free 
anastomosis  between  branches  of  the  superior  and  inferior  profunda  and 
the  anastomotica  magna,  from  the  brachial  above,  and  branches  of  the 
anterior  and  posterior  ulnar,  posterior  interosseous,  ancl  radial  recurrents 
from  the  ulnar,  interosseous,  and  radial  arteries  below.  This  anastomosis 
provides  a  collateral  circulation  in  case  of  ligature  of  the  lower  half  of 
the  bra  cliial  or  in  aneurysm  at  the  elbow. 

The  Skin. — The  skin  about  the  elbow  is  thin  and  fine  in  front,  where  it 
is  readily  excoriated  by  tight  bandages  or  poorly  applied  splints;  it  is 
thicker  and  less  sensitive  behind.  Although  the  thin  skin  in  front  allows 
the  veins  to  be  clearly  seen  through  it,  yet  in  subjects  with  much  sub- 
cutaneous fat  it  may  be  difficult  or  impossible  to  see  them.  Between  the 
^kin  and  the  olecranon  is  a  subcutaneous  bursa,  not  infrequently  the  seat 
of  the  accumulation  of  serum  or  pus  from  a  bursitis  or  of  blood  from  an 
injury.  Occupations  involving  pressure  on  the  elbow  favor  bursitis  here, 
of  which  "miner's  elbow"  is  an  example. 

The  Elbow  Joint. — The  elbow  joint  depends  for  its  strength  largely  upon 
the  shape  and  relation  of  the  bones  forming  it,  reinforced  by  the  overlying 
muscles  and  the  lateral  ligaments.  Only  flexion  and  extension  are  per- 
mitted; the  presence  of  lateral  motion  shows  that  the  ligaments  are  torn, 
stretched,  or  softened,  as  in  dislocation  or  tuberculous  disease,  and  hence 
i^  ii  sign  of  same  lesion  of  the  joint.  The  internal  lateral  is  the  strongest 
and  most  important  ligament  of  the  elbow,  and,  as  it  resists  lateral  strain  as 
well  as  limits  flexion  and  extension,  it  suffers  most  often  in  sprains  and  dis- 
locations. Its  attachment  to  the  entire  inner  border  of  the  great  sigmoid 
cavity  of  the  ulna  prevents  the  wide  separation  of  the  fragments  in  fracture 
of  the  olecranon,  for  part  of  it  is  attached  above  and  part  below  the  line 
of  fracture.  The  anterior  and  posterior  parts  of  the  capsule  are  the  weak- 
est, especially  the  posterior  portion,  which  presents  two  pouches,  one  on 
cither  side  of  the  olecranon.  As  this  is  also  the  most  superficial  part  of 
the  joint,  the  effusion  in  joint  disease  is  first  noticed  as  -a  fluctuating  swelling 
here.  The  line  of  the  radiohumeral  joint  and  the  depression  seen  behind 
it  in  extension  also  show  some  swelling  at  an  early. stage,  and  here,  or  in 
the   pouches  on  the  sides  of  the  olecranon,  especially  the  external  one, 

the  joint  may  be  aspirated  or  injected.     Beneath  the  brachialis  a  deep- 
ted   bulging  of  the  thin  anterior  part   of  the  capsule  is  also  observed 
in  effusion   into   the    joint.      Normally  the    joint   surfaces  arc   in   contact 
in  all  positions,  bul   it'  the  soft  parts  are  divided  the  radius  and  humerus 

eparate  by  a  slight  interval  when  the  capsule  is  incised,  readily  allowing 

the  knife  to  enter  tin-  joint  in  exa  rtieiila  lion. 


198 


THE   UPPER  EXTREMITY 


In  case  of  suppuration  in  the  joint  the  capsule  is  likely  to  give  way  at 
its  weakest  point,  posterosuperiorly.  The  pus  thus  comes  to  lie  between 
the  triceps  and  the  humerus,  burrows  between  them  and  points  at  either 
border  of  the  muscle,  especially  the  outer.  In  other  cases  it  may  perforate 
the  thin  anterior  ligament  beneath  the  brachialis  and  point  near  the 
insertion  of  the  latter,  especially  on  the  outer  side  on  account  of  the 
presence  of  the  bicipital  fascia  internally. 

The  diseased  elbow  is  usually  held  in  a  position  of  semiflexion,  a  position 
assumed  when  the  joint  is  forcibly  injected  (Braune),  for  in  this  position 
it  holds  the  most  fluid.  In  disease,  however,  the  position  is  probably  due 
to  a  reflex  contraction  of  the  biceps  and  brachialis  muscles,  supplied  by  the 
musculocutaneous,  which  is  the  principal  nerve  of  the  joint.     Owing 


Fig.  72 


BRACHIALIS     MEDIAN 
INTERNUS         NERVE 
MUSCLE, 
CORONOID 
PROCESS 
OF  ULNA 
PRONATOR 
TERES 
MUSCLE 


BRACHIAL 
ARTERY 


HUMERUS 


FLEXOR   CARPI 
ULNARIS    MUSCLE 


ULNAR   NERVE 


FLEXOR   CARPI, 
ULNARIS   MUSCLE 


BRACHIORAD1ALIS 
MUSCLE 


EXTENSOR  CARPI 
RADIALIS   LONGIOR 
MUSCLE 
EXTENSOR   CARPI 
RADIALIS   BREVIS 
MUSCLE 


OLECRANON  ANCONEUS 

MUSCLE 

Cross-section  at   elbow. 


partly  to  the  accurate  coaptation  of  the  ulna  and  humerus,  ankylosis 
of  the  elbow  after  injury  or  disease  is  not  uncommon.  Sudden  forcible 
straightening  of  an  ankylosed  elbow  entails  some  danger  of  rupture  of 
the  brachial  artery  at  the  bend  of  the  elbow.  If  the  elbow  is  ankylosed 
in  a  straight  or  semiflexed  position,  the  ankylosis  should  be  broken  up  or 
the  elbow  excised,  for  in  this  position  the  arm  is  not  only  useless  but  in 
the  way. 

Excision  of  the  Elbow  Joint. — In  excision  of  the  elbow  joint  the  three 
most  important  muscles  in  relation  to  it,  which  act  on  it  and  therefore 
must  be  preserved,  if  possible,  are  the  biceps,  brachialis,  and  triceps.  The 
insertions  of  the  first  two  are  readily  preserved.  The  ulna  may  be  divided 
low  enough  to  remove  the  entire  coronoid  process  without  sacrificing  the 


PLATE   XVIII 


FIG.  73 


Backward   Dislocation  of  the  Elbow. 


THE  REGION  OF   THE  ELBOW  1 99 

insertion  of  the  brachialis  into  the  tuberosity  at  its  lower  end.  The  usual 
incision  is  a  posterior  longitudinal  one  through  the  triceps,  which  is  then 
separated  from  the  olecranon  on  either  side  of  the  incision  by  longitudinal 
cuts  close  to  the  bone  (subperiosteally),  in  order,  as  far  as  possible,  to  leave 
the  triceps  insertion  connected  with  the  periosteum  of  the  bone  below  the 
point  of  section.  The  strong  expansion  from  the  outer  margin  of  the 
triceps  tendon  should  always  be  saved,  as  it  enables  the  triceps  to  retain 
a  hold  on  the  forearm.  In  freeing  the  parts  about  the  internal  condyle 
great  care  should  be  taken  to  avoid  injury  to  the  ulnar  nerve  lying  behind 
it,  bv  making  whatever  incisions  are  necessarv  close  to  bone  and  lonjn- 
tudinal.  The  nerve  should  not  be  seen.  Another  nerve  in  some  danger 
of  injury  when  the  upper  end  of  the  radius  is  being  bared  is  the  posterior 
interosseous  as  it  wrinds  around  the  radius  in  the  supinator  muscle.  It  is 
wise  to  remove  5  cm.  (2  in.)  of  bone  (including  both  humerus  and  forearm 
bones)  to  avoid  the  danger  of  re-ankylosis. 

In  connection  with  excision  in  young  subjects  under  seventeen  (when 
the  lower  humeral  epiphyseal  line  ossifies)  it  may  be  noted  that  the 
principal  growth  in  length  of  the  humerus  occurs  at  the  upper  end.  Most 
of  this  lower  epiphysis  and  the  upper  radial  epiphysis  are  within  the  joint 
and  may  be  the  starting  point  of  joint  disease  or  secondarily  involved 
by  it. 

Dislocation  of  the  Elbow — Dislocation  of  the  elbow  is  more  common 
than  that  of  any  single  joint  save  the  shoulder.  It  is  most  common  (85 
per  cent.)  in  the  first  twenty  years  of  life,  when,  according  to  Kronlein,  it 
is  the  equivalent  injury  of  dislocation  of  the  shoulder  by  indirect  violence. 

Dislocation  of  both  bones  of  the  forearm  backward  is  the  typical  form, 
being  by  far  the  most  common.  It  is  usually  due  to  a  fall  on  the  out- 
stretched hand,  by  which  the  elbow  is  hyperextended  and  often  abducted. 
It  is  only  in  hyperextension  that  the  beak  of  the  olecranon  presses  against 
the  bottom  of  the  olecranon  fossa.  It  then  serves  as  a  fulcrum  so  that 
by  continued  hyperextension  the  ulna  is  torn  as  it  were  from  the  humerus. 
The  internal  lateral  ligament  is  thereby  torn,  generally  at  its  insertion  into 
the  humerus,  the  external  lateral  ligament  is  usuallv  torn  or  detached  from 
the  humerus,  and  the  rent  extends  across  the  thin  anterior  ligament.  The 
lateral  ligaments  oppose  hyperextension  and  lateral  motion,  and  are  the 
strongest  bonds  holding  the  bones  together.  Hence  when  they  are  torn 
the  violence  continuing  forces  the  coronoid  process  far  enough  backward 

to  allow  it  to  be  pushed  up  behind  and  above  the  trochlea,  opposite  to  or 

into  the  olecranon  fossa. 

Associated  Injuries. — The  orbicular  ligament  is  rarely  injured,  and  a 
partial  preservation  of  the  external  lateral  ligament  may  affeci  the  iitti- 

tude  of  the  limb,  adducting  it,  and  render  reduction  difficult.  The 
brachialis  is  stretched,  sometimes  lacerated  and  rarely  torn  across.    The 

biceps  is  rendered  tense  and  occasionally  slips  ;i  round  the  outer  condyle. 
The  median  and  ulnar  ncrrc.s  may  be  greatly  stretched.     The  lip  of  the 

internal  condyle  is  of  ten  torn  off  and  may  be  displaced  upward  and  back- 
ward with  the  internal  lateral  ligament.  \  common  lesion  of  practical 
importance  is  the  stripping  up  of the  periosteum  ;ii  the  backoj  the  external 


200  THE   UPPER  EXTREMITY 

condyle,  often  continuous  with  the  external  lateral  ligament  and  the 
capsule  behind  the  radius.  If  the  dislocation  remains  long  unreduced,  so 
that  the  periosteum  is  held  away  from  its  place  of  attachment,  new  bone 
is  here  produced  which  interferes  with  the  extension  of  the  elbow  by 
impinging  on  the  radius.  As  complications  there  may  be  fractureoi  the 
coronoid  process,  olecranon,  head  of  the  radius  (partial  or  complete), 
and  the  shaft  or  lower  extremity  of  the  radius. 

Symptoms  and  Signs. — The  crucial  signs,  on  which,  alone  the  diagnosis 
should  rest,  are  the  relative  positions  of  the  two  condyles,  the  olecranon 
and  the  head  of  the  radius,  as  determined  by  palpation.  The  olecranon 
is  displaced  backward  and  upward,  the  backward  displacement  being 
more  marked  in  flexion,  the  upward  in  extension.  The  head  of  the  radius 
can  be  felt  and  perhaps  even  seen  under  the  skin  behind  the  external 
condyle  and  to  the  outer  side  of  the  olecranon.  In  addition  the  elbow  is 
usually  flexed  at  an  angle  of  about  135  degrees,  but  may  be  extended  or 
even  hyperextended,  and  the  lower  end  of  the  humerus  causes  a  fulness 
in  front  (below  the  crease  of  the  elbow).  When  viewed  from  in  front  the 
forearm  appears  shortened  in  front  and  broadened  above,  its  axis  may  be 
deviated  to  either  side,  flexion  and  extension  are  limited  and  painful,  and 
lateral  motion  exists. 

Reduction  is  often  accomplished  by  flexion  and  traction,  commonly 
using  the  knee  in  the  bend  of  the  elbow  as  a  fulcrum  and  to  produce 
traction.  In  this  method  the  coronoid  process  has  to  pass  down  behind 
and  then  below  the  trochlea,  and  to  do  this  the  ulna  must  be  separated 
from  the  humerus  by  more  than  12  mm.  (^  in.),  the  height  of  the  coronoid 
process.  This  can  only  occur  when  the  laceration  of  the  ligaments  and 
soft  parts  is  extensive,  or,  as  often  happens,  is  made  so  by  the  process  of 
reduction.  It  also  requires  simultaneous  elongation  of  the  muscles  of  the 
front  and  back  of  the  arm,  so  that  their  relaxation  by  anesthesia  greatly 
facilitates  the  reduction.    Forcible  pronation  may  also  facilitate  it. 

A  method  more  in  line  with  the  principle  that  a  dislocated  bone  should 
be  returned  along  the  route  by  which  it  was  displaced  with  the  least 
possible  additional  rupture  of  the  soft  parts,  is  the  method  by  traction 
upon  the  extended  or  hyperextended  forearm,  followed  by  flexion  of  the 
elbow  or  by  direct  pressure  forward  on  the  upper  end  of  the  radius  and 
ulna  and  backward  pressure  on  the  lower  end  of  the  humerus.  In  this 
method  force  is  applied  only  in  a  position  (hyperextension)  in  which  the 
arm  was  forced  in  being  dislocated,  and  no  new  damage  is  done  to  the 
ligaments  and  soft  parts. 

As  to  the  varieties  of  dislocation  at  the  elbow  it  may  be  noted:  (1)  That 
both  bones  are  more  often  dislocated  together  than  separately,  for  the 
radius  and  ulna  are  connected  by  powerful  ligaments,  the  radius  and 
humerus  are  not.  (2)  That  antero-posterior  displacements  are  much 
more  common  than  lateral  ones  on  account  of  the  lateral  width  and  the 
anteroposterior  narrowness  of  the  joint,  the  absence  of  lateral  movement 
and  the  presence  of  anteroposterior  movement,  the  feebleness  of  the 
anteroposterior  ligaments  and  muscular  support,  and  the  strength  of 
the  lateral  ligaments  and  the  support  afforded  by  the  lateral  muscles.    (3) 


THE  REGION  OF   THE  ELBOW  20 1 

That  the  rarest  dislocation  of  both  bones  is  forward,  for  it  is  resisted  by 
the  large  strong  olecranon  process.  (4)  That  if  but  one  bone  is  dislocated, 
it  is  most  often  the  radius,  for  it  is  less  strongly  connected  with  the 
humerus  and  more  exposed  to  indirect  violence  through  the  hand. 

Dislocation  of  the  radius  alone  may  occur  in  the  forward,  backward,  or 
outward  direction,  named  in  the  order  of  frequency.  In  luxation  of  the 
radius  forward  the  head  of  the  bone  arrests  flexion  of  the  elbow  at  or  near 
90  degrees  by  impact  upon  the.  humerus.  It  is  usually  due  to  falls  upon 
the  hand  while  the  elbow  is  probably  hyperextended  and  to  traction  upon 
the  forearm  probably  combined  with  extreme  pronation.  The  elboiv  is 
slightly  flexed  and  often  abducted,  and  the  forearm  is  almost  always 
pro  na  ted.  Red  net  ion  may  usually  be  accomplished  by  traction  combined 
with  supination,  adduction,  and  direct  pressure  upon  the  head  of  the 
radius,  but  it  is  sometimes  resisted  or  recurrence  favored  by  the  interposi- 
tion of  a  portion  of  the  capsule  between  the  head  of  the  radius  and  the 
capitellum. 

Dislocation  of  the  radius  by  elongation,  or  the  "subluxation  of  the  radius 
of  you  n  (j  children"  is  an  injury  quite  common  between  the  ages  of  one  and 
three,  less  common  up  to  six,  and  is  due  to  forcible  traction  on  the  extended 
elbow,  possibly  combined  with  adduction,  as  in  lifting  a  child  or  holding 
it  when  it  stumbles. 

Symptoms. — The  child  cries  with  pain,  refuses  to  use  the  elbow,  which 
i>  slightly  flexed;  the  wrist  is  pronated,  and  there  is  tenderness  over  the 
head  of  the  radius.  Passive  motion  is  free  except  for  supination.  The 
injury  consists-  in  the  escape  of  the  anterior  portion  of  the  radial  head 
below  the  orbicular  ligament,  and  is  readily  reduced  by  forcible  supination 
with  pressure  backward  on  the  head  of  the  radius  followed  by  flexion  of 
the  elbow.  It  is  sometimes  spoken  of  as  a  sprain  of  the  elbow,  and  has  also 
been  thought  to  be  a  dislocation  of  the  triangular  fibrocartilage  in  front 
of  the  lower  end  of  the  ulna  (Goyrand). 

Luxation  of  the  ulna  alone  is  usually  backward,  but  may  very  rarely  be 
forward  or  inward.  Although  all  kinds  of  dislocations  of  the  elbow  have 
been  described  as  complete  or  incomplete,  the  differences  are  often  incon- 
siderable and  unimportant.  Incomplete  Conns  are  more  liable  to  occur 
in  the  lateral  than  in  the  anteroposterior  varieties. 

Fractures  of  the  Lower  End  of  the  Humerus.     Fractures  of  the  lower 

end  of  the  humerus  are  much  more  common  than  those  of  the  upper  end 
or  of  the  shaft,  and  are  more  common  in  young  snhjects  than  in  adults. 
Various  forms  occur,  rendering  a  differential  diagnosis  accessary  and 
often  difficult. 

A.  Supracondyloid  Fractures.  Supracondyloid  fractures,  or  fractures 
through  the  expanded  portion  above  the  condyles,  are  due  to  violence, 

acting,  as  ;i   rule,  through  the  bones  of  the  forearm,  as  in  a  hill  upon  the 

hand,  pressing  the  lower  end  of  the  humerus  1 1  )  backward,  by  the  partly 

flexed  forearm  or  possibly  by  hyperextension   ("extension  fractures"); 

_'    forward  from  behind  '"flexion  fracture");  or  (3)  inward  ("adduction 

fracture"       In    l  )  the  line  of  fracture  i    oblique  from  behind  downward 

and  forward,  the  common  form  ;   in    _'    it  is  oblique  Ul  the  opposite  < I irec- 


202  THE   UPPER  EXTREMITY 

tion;  and  in  (3)  it  is  oblique  from  above  and  externally  downward  and 
inward.  Form  (3)  is  found  especially  in  children  and  the  line  of  fracture 
is  low  down  on  the  inner  side.  Forms  (1)  and  (2)  may  be  .transverse  or 
oblique  from  side  to  side.  The  character  and  extent  of  the  displacement 
vary  with  the  direction  of  the  fracture. 

In  the  common  form  (1)  the  lower  fragment  with  the  bones  of  the  fore- 
arm is  displaced,  and  sometimes  tilted,  backward  and  upward  by  the  origi- 
nal violence,  aided  perhaps  by  the  triceps,  biceps,  and  brachialis  muscles. 
Hence  the  sharp  lower  end  of  the  upper  fragment  projects  forward,  and 
the  deformity  resembles  a  dislocation,  from  which  it  may  be  distinguished 
by  the  relative  position  of  the  two  condyles,  the  olecranon  and  the  radial 
head  (see  above,  p.  194),  and  by  the  fact  that  the  displacement  is  readily 
reduced  and  as  readily  recurs.  The  displacements  to  avoid  in  the  treat- 
ment are  overriding  and  a  lateral  angular  one  in  the  position  of  adduction 
(cubitus  varus).  The  latter  is  due  to  the  support  of  the  elbow  by  the 
sling,  which  should  only  be  beneath  the  wrist,  and  perhaps  to  muscular 
action  or  a  primary  displacement  in  an  "adduction  fracture" — form  (3). 
If  the  fracture  heals  in  the  adducted  position  the  axis  of  the  forearm 
may  be  in  line  with  that  of  the  arm,  or  it  may  form  an  angle  with  it 
whose  apex  is  directed  outward  (cubitus  varus).  The  carrying  function 
of  the  arm  is  thus  lost.  The  overriding  is  corrected  by  traction  and  its 
recurrence  is  prevented  by  the  weight  of  the  arm  and  by  anterior  and 
posterior  moulded  plaster  splints. 

B.  T-shaped  or  Intercondyloid  Fracture. — A  T-shaped  or  intercondyloid 
fracture  may  be  like  the  supracondyloid  form  with  the  addition  of  a  verti- 
cal fracture  running  through  the  thin  portion  of  the  bone  between  the 
condyles  into  the  joint.  But  as  they  are  commonly  due  to  great  violence 
the  bone  is  often  much  comminuted  and  the  fractures  run  in  various 
directions,  the  essential  fracture  being  a  separation  of  both  condyles  from 
each  other  and  from  the  shaft.  On  theoretical  grounds  the  longitudinal 
ridge  of  the  sigmoid  cavity  has  been  thought  to  act  as  a  wedge  in  pro- 
ducing the  vertical  fracture  into  the  joint.  The  thinness  of  the  bone 
above  the  trochlea,  due  to  the  presence  of  the  olecranon  and  coronoid 
fossae,  favors  the  occurrence  of  such  a  fracture.  The  artery  or  nerves 
about  the  joint  may  be  torn  or  compressed  in  this  or  the  preceding  variety, 
but  less  frequently  than  might  be  expected. 

For  surgical  purposes  the  terms  epitrochlea  and  epicondyle  are  applied 
to  those  portions  of  the  internal  and  external  condyles  (respectively) 
which  are  outside  of  the  joint  capsule. 

C.  Fracture  of  the  Epitrochlea. — Fracture  of  the  epitrochlea  often  accom- 
panies dislocation  of  the  elbow,  when  it  is  probably  due  to  avulsion  by 
traction  of  the  forearm  flexor  muscles,  or  it  may  be  due  to  direct  violence 
from  behind.  The  displacement  may  be  downward  and  forward  in  the 
direction  of  the  muscles  attached  to  it,  but  the  dense  periosteo-aponeurotic 
covering  and  the  attachment  of  the  internal  lateral  ligament  prevent 
much  displacement  if  the  fragment  is  small.  In  cases  occurring  with 
dislocation  it  is  commonly  displaced  upward  and  backward.  The  epi- 
trochlea is  a  distinct  epiphysis  which  joins  the  shaft  at  about  the  age  of 


THE  REGION  OF   THE  ELBOW  203 

eighteen,  and  before  this  age  may  be  separated  from  the  shaft  instead  of 
fractured.  The  ulnar  nerve  lying  behind  it  has  been  injured  in  a  few 
cases  of  fracture  of  this  process. 

D.  Fracture  of  the  Epicondyle. — Fracture  of  the  epicondyle  is  rare,  if  it 
ever  occurs,  and  many  deny  the  possibility,  owing  to  its  small  size. 

E.  Fracture  of  the  Internal  Condyle. — Fracture  of  the  internal  condyle  is 
usually  due  to  a  fall  on  the  flexed  elbow  or  to  forced  ad-  or  abduction 
of  the  forearm.  The  line  of  fracture  extends  from  the  inner  border  of  the 
epitrochlea,  or  the  ridge  above  it,  downward  and  outward  through  the 
outer  part  of  the  trochlea,  or  even  beyond  it.  The  ulna  is  attached  to  the 
fragment,  and  much  displacement  of  these  two  is  prevented  by  the  attach- 
ment of  the  former  to  the  radius,  unless  this  is  dislocated,  as  occasionally 
happens.  A  late  lateral  displacement  in  the  adducted  position  (cubitus 
varus)  may  occur  in  this  as  in  supracondyloid  fractures,  from  the  same 
cause  (see  p.  202),  and  should  be  guarded  against.  The  relative  position 
of  the  epitrochlea  and  the  tip  of  the  olecranon  is  preserved,  and  their 
displacement  with  reference  to  the  epicondyle  is  generally  too  slight  to  be 
recognized. 

F.  Fractures  of  the  External  Condyle. — Fractures  of  the  external  con- 
dyle are  more  common  than  those  of  the  internal  condyle  and  are  especially 
frequent  in  the  young.  They  are  due  to  a  fall  on  the  hand  when  the  elbow 
is  flexed  or  upon  the  inner  and  back  part  of  the  flexed  elbow  or  to  forcible 
adduction  of  the  forearm.  The  line  of  fracture  runs  from  the  supra- 
condylar ridge  above  the  epicondyle  downward  into  the  joint  usually  to 
the  groove  of  the  trochlea,  coinciding  in  part  with  the  epiphyseal  line.  In 
children  it  is  likely  that  this  form  of  fracture  often  consists  of  a  separation 
of  the  capitellar  epiphysis,  usually  combined  with  the  splitting  off  of  a 
small  piece  from  the  outer  side  of  the  diaphysis.  As  the  fragment  is 
attached  by  ligaments  to  both  the  radius  and  the  ulna,  the  displacement  is 
usually  slight,  but  there  is  a  tendency  to  tilting  (flexion)  and  sometimes 
to  rotation  of  the  fragment.  As  in  fractures  of  the  internal  condyle,  so 
also  in  fractures  of  the  external,  there  is  independent  mobility  of  the 
condyle,  usually  with  crepitus,  abnormal  lateral  mobility,  and  pain  on 
transverse  pressure  and  at  the  point  where  the  fracture  crosses  the  supra- 
condylar ridge.  An  essential  and  sometimes  difficult  feature  of  the 
treatment  is  the  reduction  of  the  displacement.  In  both  forms,  even  w  itli 
satisfactory  reduction  of  the  displacement,  the  range  of  motion  may  be 
diminished  by  callus  obstructing  the  olecranon  or  coronoid  fossa,  etc. 

<i.  Separation  of  the  Lower  Epiphysis. --Separation  of  the  lower  epi- 
physis, as  a  whole,  is  rare  and  improbable,  except  at  an  early  age,  on 
account  of  its  irregular  outline.  The  portion  comprising  the  united 
epiphyses  of  the   radial  condyle,  eapitclhini  and   trochlea   unite  with  the 

shaft  in  the  seventeenth  year,  and  thai  portion  which  includes  the  capitellar 
and  epicondylar  nodules  is  not  infrequently  separated  in  the  elbow  injuries 

of  children  ('see  above,  F).  The  epitrochlea  unites  about  the  eighteenth 
year.      In  cases  when-  the  diagnosis  is  certain  the  fracture  has  often  been 

compound  and  the  displacement  of  the  lower  fragment  (usually  backward) 
considerable. 


204  THE  UPPER  EXTREMITY 

H.  Fracture  of  the  Olecranon. — Fracture  of  the  olecranon  is  commonly 
thought  to  be  due  to  a  fall  upon  the  elbow.  It  is  probably  not  due  to 
direct  violence  alone,  but  the  olecranon  is  firmly  held  by  the  triceps  while 
the  patient  falls  upon  the  forearm,  and  the  ulna  is  bent  about  the  trochlea 
as  a  fulcrum.  Hence  the  line  of  fracture  is  most  often  near  the  weakest 
point,  the  constriction  at  the  middle  of  the  process.  The  epiphysis  of 
the  olecranon,  which  unites  with  the  shaft  in  the  sixteenth  year,  comprises 
only  the  summit  of  the  process,  and  is  very  rarely  separated. 

The  upper  fragment  is  seldom  much  separated  by  the  action  of  the 
triceps,  as  it  is  held  to  the  lower  fragment  by  the  extension  of  the  triceps 
insertion,  the  internal  lateral  ligament,  and  its  own  aponeurotic  attach- 
ments, which  are  usually  untorn.  The  olecranon  cannot  be  drawn  by 
the  triceps  above  the  position  it  occupies  in  extension  of  the  elbow,  the 
olecranon  fossa,  unless  the  ligaments  that  bind  it  to  the  humerus  are 
torn,  which  very  rarely  happens.  In  fact,  whatever  separation  there  may 
be  is  rather  due  to  the  descent  of  the  lower  fragment  in  flexion  of  the 
elbow.  The  repair  is,  as  a  rule,  by  fibrous  union.  I  have  found  the  frag- 
ments separated  by  a  blood  clot  so  that  they  could  not  be  approximated 
without  its  removal. 

I.  Fracture  of  the  Coronoid  Process. — Fracture  of  the  coronoid  process 
is  very  rare  except  as  a  complication  of  backward  dislocation  of  the  ulna 
or  of  both  bones  of  the  forearm.  In  a  case  of  this  kind,  owing  to  its  tilting 
forward  and  interfering  with  flexion  of  the  elbow,  I  was  obliged  to  remove 
it.  It  cannot  be  caused  by  the  action  of  the  brachialis,  as  the  latter  is 
inserted  into  the  ulna  at  the  base  of  the  process  rather  than  into  the 
process  itself. 

J.  Fracture  of  the  Head  or  Neck  of  the  Radius. — Fracture  of  the  head 
or  neck  of  the  radius  is  rare.  Fracture  of  a  part  of  the  head  is  sometimes 
observed  in  dislocation  of  the  elbow.  I  have  observed  two  cases  where  a 
notch  could  be  felt  on  rotation  of  the  radius,  and  the  fragment  was  felt  in 
close  proximity  but  could  not  be  replaced,  and  was  removed  in  one  case. 


THE  FOREARM. 

This  region  extends  from  the  region  of  the  elbow  to  two  fingers'  breadth 
above  the  radial  and  ulnar  styloid  processes  (Joessel).  It  is  conical  in 
form,  flattened  from  before  backward,  especially  in  muscular  subjects, 
more  rounded  in  women,  children,  and  non-muscular  subjects  on  account 
of  the  accumulation  of  fat  in  front  and  behind  and  the  slight  development 
of  the  lateral  muscles.  On  account  of  its  conical  form  circular  amputa- 
tion without  splitting  of  the  skin  flap  is  not  appropriate  for  the  upper 
two-thirds  of  the  forearm. 

Surface  Markings  and  Landmarks. — The  ulna  can  be  felt,  along  its 
posterior  border,  the  entire  length  of  the  posterior  surface  of  the  forearm. 
In  muscular  subjects  its  position  is  marked  by  a  groove  external  to  which 
is  an  elevation,  extending  from  the  back  of  the  external  condyle  down  the 
middle  of  the  posterior  surface,  formed  largely  by  the  extensor  communis. 


THE  FOREARM  205 

Separated  from  this  by  a  groove  is  another  prominence  on  the  outer 
aspect  of  the  forearm,  formed  by  the  brachioradialis  and  the  two  radial 
extensors  of  the  wrist.    The  upper  fleshy  part  of  these  muscles  covers  the 

rod  tux  so  that  its  upper  half  cannot  be  felt.  But  in  the  lower  half  of  the 
arm  its  lateral  surface  can  be  felt,  though  less  plainly  than  the  ulna,  for  it  is 
covered  by  the  tendons  of  the  two  radial  extensors  of  the  wrist,  and  about 
5  cm.  (2  in.)  above  the  radial  styloid  process  it  is  crossed  by  the  extensors 
of  the  thumb,  which  form  a  slight  ridge  directed  obliquely  downward, 
outward,  and  forward.  On  the  anterior  surface  of  the  supinated  arm  in 
thin  subjects  two  slight  furrows  can  be  seen,  one  from  the  middle  of  the 
bend  of  the  elbow  to  a  point  just  internal  to  the  radial  styloid  process,  the 
other  from  the  internal  condyle  to  the  radial  side  of  the  pisiform  bone. 
These  two  furrows  represent  respectively  the  course  of  tltc  radial  and  the 
lotrer  tico-thirds  of  tltc  ulnar  arteries,  along  which  one  incises  to  ligate 
them.  They  also  represent  the  anterior  borders  of  the  brachioradialis 
and  the  flexor  carpi  ulnaris  respectively.  The  course  of  the  upper  third 
of  the  ulnar  artery  is  represented  by  a  line,  slightly  convex  inward, 
from  the  middle  of  the  bend  of  the  elbow  to  the  junction  of  the  middle 
and  upper  thirds  of  the  line  indicating  the  course  of  the  rest  of  the  ulnar 
artery. 

The  Skin. — The  skin  of  the  forearm  is  thin  and  movable  and  the  surface 
veins  show  through  it  unless  the  subcutaneous  fat  is  abundant.  It 
is  to  be  noted  that  over  the  middle  of  the  posterior  surface,  especially 
in  its  upper  part,  there  are  almost  no  veins  and  only  very  small  nerves, 
and  that  this  is  the  aspect  of  the  limb  most  exposed  to  injury.  The 
fascia,  which  in  the  upper  half  of  the  forearm  is  closely  attached  to  the 
muscles,  is  free  from  the  tendons  in  the  lower  half  and  attached  to  the 
posterior  borders  of  the  ulna  and  radius,  so  as  to  incompletely  divide 
the  forearm  into  two  compartments  with  the  aid  of  the  interosseous 
membrane. 

Arteries. — The  free  anastomoses  between  the  radial  and  ulnar  arteries 
are  to  be  remembered  in  wounds  of  either  vessel.  In  ligating  either  vessel 
by  an  incision  along  the  lines  just  given,  it  is  to  be  noted  that  the  sheath 
of  the  radial  is  connected  with  that  of  the  pronator  radii  teres,  in  the 
upper  half  of  the  forearm,  and  the  sheath  of  the  ulnar  with  that  of  the 
flexor  profundus,  upon  which  it  lies,  so  that  to  freely  expose  these  arteries 
the  sheaths  of  these  two  muscles  must  be  divided.  Also  in  ligating  the 
ulnar  artery  in  the  lower  two-thirds  of  the  arm  the  ulnar  nerve  is  almost 
necessarily  exposed  on  its  ulnar  side,  while  in  ligating  the  radial  artery 
the  radial  nerve  is  not  exposed,  as  it  lies  farther  to  the  radial  side  and  is 

connected  with  the  sheath  of  the  brachioradialis.     Among  the  arterial 
anomalies  of  practical  interest  may  be  mentioned :  (1)  The  perforation  of 

the  deep  fascia  by  the  radial  artery  in  the  middle  or  lower  third  of  die 

forearm  ami  it-,  subcutaneous  course  around  the  wrist  to  the  back  of  the 
first  interosseous  space;   it   can   be  easily  injured  in  its  subcutaneous 

portion, and  if  the  radial  pulse  is  sought  in  its  usual  place  it  is  weak,  being 

Furnished  by  the  smaller  superficialis  volse  branch.    (2)  In  case  of  a  high 

i>rn(i,i  of  tin-  ulnar  ttrlrri/,  from  the  axillary  or  brachial,  it  usually  pierces 


206  THE   UPPER  EXTREMITY 

the  fascia  and  becomes  superficial  a  little  above  the  elbow,  and  thence, 
passing  under  or  sometimes  over  the  bicipital  fascia,  its  course  in  the 
upper  third  of  the  forearm  is  superficial,  covered  by  the  fascia,  as  a  rule, 
but  sometimes  not. 

Skeleton  of  the  Forearm. — Of  the  two  bones,  the  ulna  is  the  stronger 
and  extends  farther  above,  the  radius  below,  and  the  two  are  most 
nearly  of  equal  strength  about  the  centre  of  the  limb.  In  all  parts  the 
two  bones  are  nearer  the  posterior  than  the  anterior  aspect,  and  especially 
so  in  the  upper  part.  They  are  nearest  the  centre  of  a  section  of  the  limb 
in  the  lower  end  of  the  middle  third.  On  account  of  the  posterior  position 
of  the  bones,  especially  the  ulna,  they  are  best  examined  or  reached  for 
excision  on  this  aspect;  also  fractures  are  most  readily  compounded 
posteriorly.  The  two  bones  approach  one  another  above  and  below  and 
are  separated  in  the  middle,  the  separation  being  widest  a  little  below 
the  middle  of  the  forearm.  In  supination  both  bones  are  parallel  in 
pronation  they  are  crossed.  The  interosseous  space  is  narrowest  in  pro- 
nation, widest  in  supination,  and  almost  equally  wide  midway  between 
pronation  and  supination,  hence  the  latter  position  is  maintained  in 
most  fractures  of  the  forearm.  In  pronation  and  supination  the  ulna 
remains  stationary,  the  radius  revolving  around  it  describes  a  section  of  a 
cone  whose  apex  is  above  in  the  centre  of  the  radial  head  and  the  base 
below.  Supination  is  the  stronger  of  the  two  movements;  thus  in  using 
a  screw-driver,  gimlet,  or  cork-screw  the  main  force  is  applied  during 
supination.  In  ordinary  pronation  and  supination  there  is  some  flexion 
and  extension  of  the  elbow  and  rotation  of  the  shoulder  in  addition  to 
rotation  of  the  radius.  The  oblique  ligament  helps  to  hold  the  radius  in 
contact  with  the  humerus  through  the  medium  of  the  ulna.  The  obliquity 
of  the  fibers  of  the  interosseous  membrane  (from  above  and  without 
downward  and  inward)  makes  the  ulna  share  with  the  radius  in  the  strain 
of  the  latter  in  resting  on  or  pushing  with  the  palm,  and  communicates  to 
the  radius  the  force  imparted  to  the  ulna  in  a  blow  from  the  shoulder. 

Fractures  of  the  Shafts  of  the  Radius  and  Ulna. — Fractures  of 
the  shafts  of  the  radius  and  ulna  may  be  due  to  direct,  indirect,  or  rarely 
to  muscular  violence.  Fracture  of  the  ulna  alone,  the  more  superficial 
and  exposed  of  the  two  bones,  is  almost  invariably  the  result  of  direct 
violence,  such  as  a  fall  upon  the  ulnar  side  of  the  forearm  or  a  blow  on 
the  arm  raised  to  protect  the  head,  for  in  this  position  the  ulna 
becomes  uppermost.  Fracture  of  the  radius  alone  is  also  generally 
due  to  direct  violence,  but  is  more  often  the  result  of  indirect  violence 
than  fracture  of  the  ulna,  for  it  receives  all  shocks  transmitted  from 
the  hand.  According  to  Malgaigne,  "green-stick  fractures"  are  more 
common  in  the  forearm  than  elsewhere. 

The  displacement  varies  greatly  with  the  direction  of  the  fracture  and 
the  fracturing  force,  so  that  we  may  find  overriding,  lateral  or  angular 
displacement.  In  some  cases  it  is  affected  by  muscular  action.  Thus  in 
fracture  of  the  radius  alone  above  the  insertion  of  the  pronator  teres  the 
upper  fragment  may  be  fully  supinated  by  the  biceps  and  supinator 
(brevis),  while  the  lower  fragment  is  maintained  by  the  splints  in  the 


THE  FOREARM  207 

usual  position  midway  between  supination  and  pronation.  If  union 
occurs  with  the  fragments  in  these  relative  positions,  the  power  of  supi- 
nation will  be  lost  as  the  supinators  can  act  no  farther.  A  similar  result 
may  follow  after  fractures  of  both  bones.  Another  important  displace- 
ment that  may  be  due  partly  or  entirely  to  muscular  action  in  fracture  of 
one  or  both  bones  between  the  two  pronators  is  that  in  which  the  two 
bones  approach  one  another.  The  upper  fragments  of  both  bones,  or  of 
the  radius  alone,  may  be  drawn  toward  the  opposite  bone  by  the  pronator 
teres;  and  the  lower  fragments  of  both  or  either  bone  may  be  similarly 
made  to  approach  the  opposite  bone  by  the  pronator  quadratus  and  the 
1  nachioradialis.  The  resulting  diminution  of  the  interosseous  space  or  the 
actual  osseous  union  between  the  two  bones  interferes  with  or  entirely 
prevents  rotation  of  the  radius,  for  the  performance  of  which  the  inter- 
osseous space  is  essential.  Excessive  formation  of  callus  may  produce  a 
similar  result,  and  angular  displacement  is  its  most  frequent  cause.  In 
the  latter  case  the  radius  of  rotation  is  increased  at  the  apex  of  the  dis- 
placement in  the  radius,  and  full  supination  is  prevented  by  the  inter- 
osseous membrane,  for  to  become  fully  supinated  the  angle  in  the  radius 
must  move  farther  from  the  ulnar  than  normally.  Actual  bony  union 
of  the  two  bones,  which  is  very  rare,  is  more  likely  to  occur  when  both 
bones  are  broken  at  the  same  level,  but,  as  a  rule,  the  radius  is  broken 
nearer  the  elbow  than  the  ulna. 

The  upper  fragment  of  the  radius  may  also  be  drawn  forward  by  the 
biceps  and  pronator  teres.  In  general,  when  only  one  bone  is  broken  the 
other  acts  as  a  splint  to  prevent  marked  displacement,  except  the  rotary 
(supination)  displacement  of  the  radius  and  the  approach  of  one  or  both 
fragments  to  the  opposite  bone.  In  fracture  of  the  ulna  alone  marked 
displacement  of  its  fragments  may  occur  in  case  of  the  not  infrequent 
complication  of  dislocation  of  the  head  of  the  radius  forward. 

Treatment. — In  treatment  the  following  points  should  be  observed 
after  the  displacement  is  corrected  as  perfectly  as  possible,  for  this  is  of 
the  utmost  importance  to  preserve  function.  If  there  is  any  tendency  to 
supination  of  the  upper  fragment  of  the  radius,  the  forearm  should  be 
placed  in  the  supine  position,  so  that  after  union  the  power  of  supination 
may  be  preserved.  In  order  to  avoid  as  far  as  possible  the  union  of  the 
tiro  bones,  and  the  consequent  loss  of  rotation,  the  forearm  should  be 
placed  in  a  position  in  which  the  interosseous  interval  is  wide,  i.  e.,  in  the 
position  midway  between  pronation  and  supination.  The  position  of 
complete  supination  would  serve  best,  for  in  it  the  interval  is  widest,  but 
it  is  more  irksome  to  the  patient.  With  the  object  of  preventing  union 
between  the  two  bones  the  use  of  graduated  pads  have  been  advised  to 
fon-e  the  bones  apart  by  pressure.  But  this  pressure,  as  well  as  any 
Undue  pressure  of  the  splints  and  bandages,  is  in  danger  of  producing 
gangrene  of  the  limb,  which  is  more  common  after  fracture  of  the  forearm 

than  after  fracture  elsewhere.    This  is  owing  to  the  fact  that  most  of  the 

venous  blood  is  returned  by  the  surface  veins,  which,  as  well  as  the  main 
arteries,  are  readily  affected  by  pressure.     This  pressure  of  the  forearm 

is  also  liable  to  produce  ischemic  paralysis  a  nil  contraction  of  the  muscles 


208  THE  UPPER  EXTREMITY 

which  occur  mostly  in  the  forearm  and  nearly  destroy  the  usefulness  of 
the  hand.  The  tendency  to  overriding,  which  may  be  maintained  by  the 
tension  of  the  muscles,  may  be  largely  overcome  by  flexion  of  the  elbow 
and  of  the  wrist,  which  relaxes  these  muscles. 

Amputation  of  the  Forearm. — In  amputation  of  the  forearm  the  flap 
method  is  best  suited  to  the  upper  two-thirds,  the  circular  to  the  lower 
third.  In  the  latter  part  the  soft  parts  are  mostly  skin  and  tendons  and 
the  bones  come  closer  to  the  sides  of  the  limb,  so  that  the  flap  method  is 
unsuitable.  As  the  soft  parts  divided  are  mostly  tendons  they  are  more 
easily  and  cleanly  divided  from  within  outward  by  transfixion.  Arteries 
and  nerves  divided:  (Fig.  74.)  On  the  sides  of  the  anterior  or  flexor 
aspect  of  the  cut  surface  are  the  radial  and  ulnar  arteries,  the  former 
no  longer  accompanied  by  its  nerve,  the  latter  with  the  ulnar  nerve 
to  its  inner  side.  In  front  of  the  interosseous  membrane  is  the  anterior 
interosseous  artery,  and  with  the  median  nerve,  in  the  posterior  layer 
of  the  sheath  of  the  flexor  sublimis,  is  the  median  artery,  sometimes 
of  large  size.  Posteriorly  between  the  deep  and  superficial  layers  of 
muscles  are  the  posterior  interosseous  nerve  and  artery. 

In  the  upper  two-thirds  of  the  arm,  where  the  muscular  masses  cover 
the  bones  at  the  sides  and  the  limb  is  more  flattened  and  conical,  ampu- 
tation by  anteroposterior  flaps  is  more  suitable.  The  anterior  flap  con- 
tains the  brachioradialis  and  the  flexor  muscles,  the  posterior  flap  the 
extensor  muscles.  The  anterior  flap  is  more  substantial,  as  the  bones 
lie  nearer  the  posterior  surface.  The  radial  artery,  with  the  radial  nerve 
on  its  radial  side,  runs  the  whole  length  of  the  anterior  flap  and  is  cut 
near  its  outer  border,  internal  to  the  brachioradialis.  The  ulnar  artery 
is  cut  at  a  higher  level,  in  front  of  the  ulna  and  between  the  superficial 
and  deep  flexors.  The  anterior  interosseous  artery  is  cut  short  just  in 
front  of  the  interosseous  membrane,  the  posterior  interosseous  is  cut  long 
between  the  superficial  and  deep  muscles.  The  principal  nerves  are  good 
guides  to  the  corresponding  vessels,  except  the  ulnar  nerve  in  the  upper 
third. 

It  may  be  noticed  in  this  connection  that  the  ulnar  artery  gives  off 
the  interosseous  trunk  2.5  cm.  (1  in.)  below  the  bifurcation  of  the  brachial, 
which  occurs  opposite  the  upper  part  of  the  neck  of  the  radius.  As  the 
chief  pronators  are  the  pronators  teres  and  quadratus  and  the  flexor 
carpi  radialis,  and  the  chief  supinators  are  the  biceps  and  supinator 
(brevis),  it  follows  that  in  amputation  above  the  insertion  of  the  pronator 
teres  (the  middle  of  the  forearm)  the  radius  will  become  supinated  and 
its  further  rotation  lost. 


THE  REGION  OF  THE   WRIST. 

This  region  may  be  artificially  limited,  according  to  Tillaux,  by  planes 
two  fingers'  breadth  above  and  below  the  radiocarpal  joint. 

Surface  Markings  and  Landmarks. — The  radial  and  ulnar  styloid 
processes  can  always  be  made  out  and  are  the  most  important  landmarks 


PLATE   XIX 


FIC.  74 


MEDIAN    VEIN 


BRACH.-RAD  — 
MUSCLE 
RADIAL    ARTERY- 
RADIAL    NERVE ■ 
EXT.     CARP._ 
RAD.     BREVIS 
MEDIAN    ARTERY- 


SUPIN  ATOR_h_i  . 

ANTERIOR    INTFR-    V    ■ 
OSSEOUS   ARTERY 
EXT.    COM.    DIGIT. 


FLEXOR 

CARPI     RAD. 
PRONATOR 
CT  TERES 


l-~  A        MEDIAN    NERVE 
i«V.\V\      FLEXOR    SUBL. 

Bi\CT       DIG|T- 

iWWjJ'il  ULNAR    ARTERY 

ULNAR    NERVE 

$1  .   II    FLEXOR    CARPI 
Uyjl  ULNARIS 


POSTERIOR    INTER 
OSSEOUS    NERVE 


FLEXOR     PROF. 
DIGIT. 


Cross-section  of  Right  Forearm  at  Lower  End  of  Upper  Third. 
Proximal  side  of  section,  from  below.     (Joessel.) 


FIG.  75 


FLEXOR 
LONGUS 
POLLICIS.  FLEXOR 

RADIAL  CARPI 

ARTERY  IRADIALIS 


MEDIAN     SUPERFIC. 
NERVE        LAYER   OF 


FASCIA 

FLEXOR 

PRO- 


FLEXOR 
SUBLIMIS 


BRAC 
RADIA 


RADIAL 
NERVE 
EXT      OSSIS. 
METACARPI 
POLLICIS 


RADIAL    CARPAL 
EXTENSORS 


EXT.     LO 
POLLI 


NATOR 
ADRATUS 
NAR 


FLEXOR 
CARPI 

ULNARIS 


EXTENSOR    COM- 
MUNIS   D'  = 


ANT.     INTEROSS- 
EOUS   ARTERY 


Cro-    -   e<  non  of   Right  Wrist,  \yz  cm.  above    Articular  Surface. 
Upper  segment  of  the   section.     (Tillnux.) 


THE  REGIOX  OF   THE   WRIST  209 

for  examination  of  or  operations  on  the  wrist.  The  radial  styloid  process, 
a  ringer's  breadth  above  the  thenar  eminence,  is  more  anterior  and 
descends  nearly  12  mm.  (^  in.)  lower  than  that  of  the  ulna.  Partly  on 
account  of  this  fact  abduction  is  less  free  than  adduction  of  the  hand. 
In  the  female  the  x-rays  show  that  position  of  the  articular  surface  of  the 
radius  as  compared  with  that  of  the  ulna  is  decidedly  lower  than  in  the 
male  (Stimson).  The  radial  styloid  is  commonly  carried  upward  in 
Colles'  fracture  so  as  to  be  on  a  level  with  or  above  the  ulnar  styloid, 
a  point  of  diagnostic  importance  (Fig.  79).  Just  beneath  the  radial 
and  ulnar  styloid  processes  one  enters  the  radiocarpal  joint,  the  line 
of  which  is  concave  inferiorly  and  rises  1  cm.  above  that  connecting 
the  styloid  processes.  In  pronation  of  the  forearm  the  ulnar  styloid 
process  is  less  distinct  and  the  bony  prominence  at  the  back  of  the  ulnar 
side  of  the  wrist  is  due  to  the  head  of  the  ulna.  The  ulnar  styloid  process 
is  most  plainly  felt  in  supination,  at  the  inner  and  posterior  aspect  of  the 
wrist,  to  the  inner  side  of  the  extensor  carpi  ulnaris  tendon. 

In  front  of  the  wrist  are  several  skin  creases,  of  which  the  lowest  and 
most  distinct  is  slightly  convex  downward  and  is  about  1  cm.  (f-  in.) 
below  the  radiocarpal  joint  (Tillaux).  If  the  line  of  this  crease  is  con- 
tinued around  the  back  of  the  wrist  it  crosses  the  neck  of  the  os  magnum 
in  the  line  of  the  third  metacarpal  bone.  This  point  is  felt  as  a  depression 
in  extension  of  the  wrist,  but  is  replaced  by  a  prominence,  the  head  of 
the  os  magnum,  in  flexion  of  the  wrist.  This  crease  also  indicates  fairly 
well  the  upper  border  of  the  anterior  annular  ligament,  which  corresponds 
to  the  lower  border  of  the  posterior  annular  ligament.  Above  both  the 
thenar  and  the  hypothenar  eminences  is  a  slight  depression,  which  in 
Colles'  fracture  forms  a  marked  angular  depression  and  serves  as  an 
excellent  sign  of  this  injury  (Tillaux).  Extending  downward  from  the 
point  where  the  flexor  carpi  radialis  tendon  crosses  the  lower  skin  crease 
a  bony  ridge  can  be  felt,  formed  by  the  tubercle  of  the  scaphoid  and  the 
ridge  of  the  trapezium.  Corresponding  to  this  level  at  the  base  of  the 
hypothenar  eminence  the  pisiform  bone  can  be  still  more  readily  felt. 
Below  the  bead  of  die  ulna  at  the  back  of  the  wrist  the  cuneiform  bone 
may  be  felt  as  a  slight  prominence. 

Topography.  The  Front  of  the  Wrist  (Fig.  70).— On  the  radial  side 
in  the  groove  between  the  tendons  of  the  brachioradialis  and  flexor  carpi 
radialis,  u  hidi  i-,  most  marked  when  the  wrist  is  semiflexed,  can  be  felt  the 
radial  artery.  This  is  very  superficial,  lying  just  beneath  the  fascia,  and 
hence  easily  exposed,  compressed,  or  wounded.  It  is  here  that  the  pulse 
is  taken  and  arterial  sclerosis  Looked  for.  It  continues  down  (•>  a  point 
jtlSt  below  the  styloid  process.     To  the  ulnar  side  of  die  flexor  radialis 

tendon  i-.  the  most  prominent  tendon  of  this  region,  thai  of  the  palmaris 
longus.    It  is  made  most  prominent  when  the  wrist  is  partly  flexed,  the 

thenar  and  hypothenar  eminences  adducted  and  die  fingers  extended. 
It  is  near  the  centre  of  the   wrist.      In   the  groove  between   the  two  last 

named  tendons,  or  beneath  the  tendon  of  the  palmaris  longus,  is  the 
median  nerve  covered  by  the  deep  fascia.  As  the  palmaris  longus  is  not 
seldom  wanting,  the  flexor  carpi  radialis  tendon  is  the  better  guide  to  the 

1 1 


210 


THE  UPPER  EXTREMITY 


nerve,  which  lies  between  it  and  the  flexor  sublimis.  On  the  ulnar  side 
the  flexor  carpi  ulnaris  can  be  felt  extending  to  the  pisiform  bone.  It  is 
made  most  prominent  by  slight  flexion  of  the  wrist  and  adduction  of  the 
little  finger.  In  the  groove  to  its  radial  side,  between  it  and  the  more 
deeply  placed  flexor  sublimis  tendons,  lie  the  ulnar  artery  and  nerve,  the 
latter  close  to  the  ulnar  side  of  the  artery.  The  artery  and  nerve  are 
covered  by  a  deep  and  a  superficial  layer  of  the  deep  fascia  of  the  forearm, 
but  pierce  the  deep  layer,  which  is  connected  with  the  sheath  of  the  flexor 


Fig.  76 


FLEX.    CARPI    RAD.    M. 

FLEX.   LONG.   POLL.   M. 

TENDON   OFSUP1N.   LONG.   M. 

PRON.  QUAD.    M. 
RADIAL  ARTERY 

SUPERFICIALIS  VOL/E  ARTERY 

MEDIAN   NERVE 
FLEX     BREV.   POLL.    M 

FIRST   LUM  ERIC.    M._ 
ADD.    POLL.    M 


FLEX.   SUBL.   DIG.   M 


FLEX.    PROF.    DIG.    M. 
TENDON  SHEATH  OPENED 


PALM.    LONG.    M. 

MEDIAN    NERVE 
FLEX.  SUBL.    DIG.   M. 

-FLEX.  CARPI   ULN.   M. 

ULNAR  ARTERY 
ULNAR    NERVE 
PALM.   BREV.    M. 
PALM.    FASCIA 


ANAST.  OF  MED. 

NERVE  WITH  ULNAR 
NERVE 


Palmar  aspect  of  right  hand.      Superficial  layer.      (Joessel.) 


sublimis,  just  above  the  anterior  annular  ligament,  in  order  to  pass  in 
front  of  the  latter.  The  synovial  sheath  for  the  superficial  flexors  and  that 
for  the  long  flexor  of  the  thumb  extend  up  the  wrist  above  the  annular 
ligament  for  3  to,3.5  cm.  (1^  to  1^  in.)  (Fig.  82).  The  structures  above 
named  at  the  front  of  the  wrist  lie  upon  or  in  front  of  the  pronator  quad- 
ratus  muscle. 

At  the  outer  aspect  of  the  wrist  the  outer  surface  of  the  radius  is  crossed 
by  the  tendons  of  the  extensor  ossis  metacarpi  pollicis  and  extensor 
brevis  pollicis.  These  tendons  are  made  very  prominent  by  extension 
and  abduction  of  the  thumb,  in  which  position  they  bound  externally  a 


PLATE  XX 


FIG.  77 


EXTENSOR    COMMU- 
NIS    DIGITORUM 
EXTENSOR    MINIMI— 
DIGITI 
EXTENSOR    CARPI 
ULNARIS 


EXTENSOR    OSSIS 
METACARPI     POLLICIS 
^—EXTENSOR    BREVIS    POLLICIS 
-EXTENSOR    LONGUS    POLLICIS 


EXTENSOR  CARPI 
-—  RAOIALIS  BREVIS 
-      EXTENSOR    CARPI 

RADIALIS    LONGUS 


ABDUCTOR 

I  N DICIS 


Synovial  Membranes  ol'Tendons  on  the  Dorsum  of  the  Forearm 
and  Hand,  artificially  distended.     (Gerrish,  after  Testut.  | 


THE  REGION  OF  THE  WRIST  2  1  I 

depressed  triangular  space,  the  "snuff-box  space"  or  "tabatiere  anato- 
mique"  of  French  writers,  whose  ulnar  boundary  is  formed  by  the  exten- 
sor longus  pollicis  tendon.  The  floor  of  the  space  is  formed  by  the  scaphoid 
and  trapezium  with  their  dorsal  ligaments,  over  which,  and  beneath 
the  above  tendons,  runs  the  radial  artery  in  its  course  from  just  below  the 
apex  of  the  styloid  process  to  the  back  of  the  first  interosseous  space.  The 
artery  is  here  covered  by  two  layers  of  fascia,  the  deeper  of  which  holds  it 
close  to  the  carpal  bones.  Subcutaneously  the  radial  vein  and  branches 
of  the  radial  nerve  cross  this  space,  the  latter  vertically,  so  that  incisions 
to  reach  the  artery  should  be  made  vertically.  The  tendons  which  cross 
the  outer  and  dorsal  surfaces  of  the  lower  end  of  the  radius  occupy 
grooves  bounded  by  ridges,  of  which  that  on  the  radial  side  of  the  groove 
for  the  extensor  longus  pollicis  is  prominent  subcutaneously.  The  groove 
for  this  tendon  indicates  the  centre  of  the  combined  dorsal  and  external 
surfaces  of  the  radius,  and  corresponds  about  to  the  interval  between  the 
scaphoid  and  semilunar  bones.  Between  the  two  grooves  for  the  exten- 
sors of  the  thumb  is  one,  sometimes  subdivided  by  a  low  ridge,  for  the 
short  and  long  radial  extensors  of  the  wrist. 

On  the  dorsal  surface  of  the  wrist  on  the  ulnar  side  of  the  extensor 
longus  pollicis  is  a  shallow  groove  for  the  extensor  communis  and  exten- 
sor indicis,  next  to  this,  and  between  the  two  bones  is  a  groove  for  the 
extensor  minimi  digiti  and  between  the  head  and  styloid  process  of  the 
ulna  is  a  groove  for  the  extensor  carpi  ulnaris. 

The  order  and  relations  of  the  tendons  at  the  wrist  are  given  in  detail, 

as    they  are    not    infrequently  severed  in  wounds  and  require  tendon 

.suture,  for  which  an  accurate  knowledge  of  their  position  and  relations 

•  ntial,  though  when  necessary  the  distal  part  of  a  tendon  may  be 

grafted  into  another  muscle  or  tendon  with  good  results. 

The  six  grooves,  for  the  tendons  at  the  back  and  outer  side  of  the  wrist, 
are  converted  into  as  many  osseo-aponeurotic  canals  by  the  posterior 
annular  I iga iiirut,  which  binds  down  the  tendons  and  prevents  their 
displacement  in  byperextension  of  the  wrist.  This  ligament  is  con- 
tinuous with  and  a  thickening  of  the  fascia  of  the  dorsum  of  the  forearm 

and  hand.  In  these  six  canals  the  tendons  are  surrounded  by  synovial 
sheaths  (Fig.  77).  The  sheaths  of  the  three  carpal  extensors  and  the 
extensor  OSsis   metacarpi  pollicis  extend  to  or  nearly  to  the  insertion  of 

their  tendons;  thai  of  the  extensor  indicis  is  \evy  short;  the  sheaths 

of  the  other  tendons  extend  a   varying  distance  onto  the  dorsum  of  the 

hand,  from  the  upper  border  to  the  middle  of  the  metacarpus.  All 
the  sheaths  begin  above  near  or  a  little  above  the  upper  border  of  the 
annular  ligament. 

The  sheath   of   the  extensor  OSsis   metacarpi  and    the  extensor  b  re  vis 

pollicis  is  the  one  mos!  often  inflamed  in  the  so-called  tenosynovitis 
crepitans.     This  is  accompanied  by  swelling,  pain,  and  crepitation  on 

motion,   and    is   due    to    injury  or  iinn-mal    use   of    those    muscles,  g<>nt, 
Lire,  etc.     These  tendons  and  tendon  sheaths  are  liable  to  adhere  to 
the  bone,  etc.,  a  nd  to  each  other  after  ( 'olles'  I'racl  me,  and  cause  slill'ness 
of  the  v-  ri   I  a  nd  huge: 


212  THE  UPPER  EXTREMITY 

The  Wrist  Joint. — The  strength  of  the  radiocarpal,  or  wrist  joint, 
depends  upon  the  number  of  strong  ligaments  and  tendons  that  surround 
it,  the  absence  of  a  long  lever  on  its  distal  side  and  the  nearness  of  the 
numerous  small  bones  and  joints  of  the  hand  among  which  movements 
and  shocks  are  distributed.  Its  movements  are  largely  supplemented  by 
those  of  the  mediocarpal  joint.  In  the  wrist  joint  proper  extension  is 
most  free,  and  its  strongest  ligament  is  the  anterior  which  limits  hyper- 
extension.  It  is  noteworthy  that  the  commonest  injury  is  received  during 
forced  extension,  for  in  falls  one  naturally  falls  upon  the  palm,  the  wrist 
being  extended,  rather  than  upon  the  dorsum  of  the  hand,  the  wrist  being 
flexed.  The  dorsal  ligament  is  so  thin  and  superficial  that  swelling  is  first 
noticed  at  the  back  of  the  wrist  in  effusion  into  the  joint.  In  disease  of 
the  joint  the  latter  is  held  midway  between  flexion  and  extension,  as  the 
tendons  at  the  front  and  back  are  about  equally  strong.  If  the  wrist 
joint  is  injected  one  notices,  especially  on  the  dorsum,  little  hernial  pro- 
trusions of  the  synovial  membrane,  from  which  are  derived  most  of  the 
ganglia,  or  "weeping  sinews,"  which  are  so  common  in  this  situation. 
At  first  these  communicate  with  the  joint,  but,  as  a  rule,  this  communi- 
cation becomes  obliterated  as  the  pedicle  becomes  lengthened.  This 
pedicle  may  often  be  followed  by  dissection  as  a  fibrous  cord  connecting 
the  ganglion  with  the  surface  of  the  joint  capsule.  Similar  protrusions 
are  to  be  found  on  the  synovial  sheaths  of  the  tendons,  but  these  are  much 
less  often  the  starting  point  of  ganglia. 

Dislocations  of  the  Wrist. — Dislocations  of  the  wrist  are  not  common, 
for  in  the  common  form  of  violence,  due  to  a  fall  on  the  palm,  the  joint 
is  protected  by  the  strong  anterior  ligament,  and  fracture  of  the  lower 
end  of  the  radius  almost  invariably  results.  The  dislocation  is  usually 
backward,  less  often  forward,  of  the  carpus  on  the  forearm.  It  is  usually 
due  to  great  violence,  and  hence  is  often  compound  and  sometimes  com- 
plicated by  rupture  of  tendons  or  fracture  of  the  styloid  processes  or  of 
adjacent  bones.  "Barton's  fracture,"  or  the  chipping  off  of  the  posterior 
edge  of  the  articular  surface  of  the  radius,  may  occur  in  backward  dis- 
locations. I  have  seen  a  compound  backward  dislocation  in  which  the 
semilunar  bone  projected  forward  through  the  anterior  wound,  and  was 
almost  entirely  detached.  Both  forms  of  dislocation  may  be  due  to  vio- 
lence applied  to  the  flexed  or  extended  wrist.  The  deformity  of  backward 
dislocation  closely  resembles  that  of  Colles'  fracture,  but  in  the  former  the 
swelling  in  front  of  the  wrist  extends  farther  down  and  ends  more 
abruptly;  that  at  the  back  of  the  wrist  is  more  sharply  outlined  at  its 
upper  border.  In  addition  the  hand  is  usually  more  flexed  and  less 
movable  in  dislocation. 

In  the  inferior  radio-ulnar  joint  the  triangular  fibrocartilage  is  the  prin- 
cipal ligament  and  the  strongest  ligamentous  connection  between  the 
two  bones.  The  synovial  cavity  of  this  joint  is  usually  separate  from  that 
of  the  radiocarpal  joint.  Dislocation  of  this  joint,  apart  from  that  some- 
times observed  in  connection  with  Colles'  fracture,  is  rare.  It  is  usually 
forward  or  backward  of  the  ulna.  In  the  latter  form  it  is  usually  due  to 
exaggerated  pronation,  so  that  the  hand  is  pronated  and  supination  is 


Normal  Wrist.      Adult  Male. 

FIG.   79 


>nt  Colle  'Fracture.     Comminution.     Mnic,  mm'-h   forty-rive 

Si  mi   on. ) 


THE  REGION  OF  THE  WRIST  213 

interfered  with.  The  forward  form  has  been  due  to  direct  violence  acting 
upon  the  two  bones  in  opposite  directions  while  the  hand  is  supinated. 
The  wrist  may  be  pronated  or  supinated,  and  rotation  is  difficult  and 
painful.  The  ulna  is  prominent  at  the  front  or  back  of  the  wrist  according 
to  the  form  of  dislocation.  Some  surgeons  have  thought  that  the  injury 
described  above  (p.  201)  as  subluxation  of  the  head  of  the  radius  in  young 
children  is  a  dislocation  of  the  lower  end  of  the  ulna. 

Colles'  Fracture. — Colles' fracture  is  one  through  the  lower  end  of  the 
radius  from  12  to  25  mm.  (h  to  1  in.)  above  its  articular  surface,  at  or 
near  the  point  where  the  compact  tissue  of  the  shaft  joins  the  cancellous 
tissue  of  the  lower  extremity  of  the  bone,  which  appears  to  be  a  weak 
spot.  It  is-  one  of  the  commonest  fractures,  and  is  most  frequent  in  the 
elderly.  The  direction  is  transverse,  often  with  a  slight  obliquity  upward 
and  backward  and  sometimes  with  a  moderate  slant  upward  and  outward. 
The  lower  fragment  sometimes  shows  a  moderate  backward  displacement, 
and  there  is  usually  considerable  backward  and  often  some  outward 
rotation.  Thus  the  articular  surface  looks  downward  and  backward 
instead  of  downward  and  forward  as  normally.  The  rr-rays  show  that 
the  displacement  is  less  than  commonly  supposed,  and  that  the  typical 
deformity  may  be  present  when  the  displacement  is  slight,  being  due  to 
the  swelling  of  the  soft  parts.  Impaction  of  the  upper  fragment  into  the 
cancellous  tissue  of  the  dorsal  and  lateral  part  of  the  lower  is  the  rule, 
and  comminution  of  the  lower  fragment  is  frequent.  In  addition,  the 
ulnar  styloid  process  may  occasionally  be  fractured  by  avulsion,  by  means 
of  the  internal  lateral  ligament  rather  than  by  the  fibroeartilage. 

The  deformity  in  typical  cases  is  characteristic.  The  prominence  on  the 
dorsum  over  the  lower  fragment,  due  to  its  backward  displacement  and 
rotation  and  to  swelling,  gave  origin  to  the  name  "silver  fork  fracture," 
given  by  Velpeau,  on  account  of  the  resemblance  of  its  outline  as  seen 
From  the  radial  side.  The  end  of  the  ulna  is  very  prominent  in  front  on 
account  of  the  displacement  upward,  backward,  and  somewhat  outward 
of  the  lower  fragment  of  the  radius  with  the  carpus,  which  preserves 
its  relations  with  it.  The  prominence  in  front  over  the  lower  end  of  the 
upper  fragment  is  mostly  due  to  swelling  of  the  soft  parts.  The  radial 
styloid  is  displaced  up  to  or  above  the  level  of  the  ulnar  styloid  and  the 
transverse  creases  in  front  of  the  wrist  are  deepened.  Crepitus  and 
abnormal  mobility  are  not  present  in  cases  with  marked  impaction  and 
may  not  be  easily  recognizable  in  other  cases. 

The  eau.se  of  Colics'  fracture  is  almost  always  ;i  fall  upon  the  palm 
of  the  hand.  The  mechanism  is  neither  simple  oor constant,  and  has  been 
and  still  is  ;i  much  disputed  point.  (1)  The  fracture  is  due  to  a  crushing 
of  the  cancellous  tissue  between  the  carpus  and  the  shaft,  the  weight  of 
the  body  being  received  in  the  long  axis  of  the  radius  while  it  is  within 
30 degrees  of  the  vertical.  (2)  The  axis  of  the  radius  being  more  oblique 
and  not  in  line  with  the  fall,  the  force  is  decomposed ,  part  of  it  passing 

up  the  IkiI'i  in  the  long  axis  of  the  radius  and  pari  acting  transversely 
to  break  the  bone  at  its  weakest  point.  The  backward  rotation  and 
displacement  of  the  lower  fragment  indicates  the  direction  of  this  latter 


214  THE  UPPER  EXTREMITY 

part  of  the  force.  (3)  The  fracture  is  due  to  a  cross-strain  exerted  on  the 
lower  end  of  the  radius  through  the  strong  anterior  ligament,  made 
tense  by  hyperextension  of  the  hand.  The  bone  is  broken  by  avulsion 
on  the  principle  that  a  stout  ligament  is  stronger  than  cancellous  bone, 
so  that  the  latter  gives  way  first.  Most  fractures  are  probably  produced 
in  one  or  the  other  of  the  first  two  ways.  There  is  no  doubt  that  it  can  be 
and  sometimes  is  produced  by  avulsion.  This  theory  rests  upon  experi- 
ments on  the  cadaver,  and  is  supported  by  many  French  and  German 
writers  on  surgical  anatomy  (Tillaux,  Joessel,  etc.). 

Epiphyseal  separation  is  probably  more  often  due  to  this  mechanism. 
The  epiphysis  joins  the  shaft  in  the  twentieth  year;  it  includes  the  inser- 
tion of  the  brachioradialis  and  the  facet  for  the  ulna.  The  line  of  the 
epiphyseal  cartilage  is  nearly  horizontal  and  may  be  intrasynovial  inter- 
nally. Arrest  of  growth  of  the  radius  has  followed  epiphyseal  separation 
in  young  subjects. 

Complete  reduction  of  the  displacement  in  Colles'  fracture  is  often 
difficult,  but  is  essential  to  prevent  permanent  deformity  and  to  insure 
perfect  function.  In  some  cases,  especially  in  adults,  complete  reduction 
of  the  deformity  is  impossible  on  account  of  the  crushing  and  comminu- 
tion. In  such  cases  some  permanent  shortening  of  the  radius  and  promi- 
nence of  the  ulna  is  inevitable.  In  spite  of  such  persistent  moderate 
displacement  the  function  of  the  wrist  may  be  very  good.  Retention  is 
easy  after  reduction. 

Amputation  at  the  Wrist  Joint. — Amputation  at  the  wrist  joint  is 
rarely  performed.  Its  principal  object  is  to  save  the  movements  of  prona- 
tion and  supination.  In  most  cases  of  injury  it  will  either  be  necessary 
to  amputate  higher  or  it  will  be  possible  to  save  more,  even  a  finger,  which 
is  most  desirable.  In  cases  of  disease  the  necessary  skin  covering  is 
involved  and  the  movements  of  rotation  are  often  lost  from  the  disease. 
In  general,  amputations  in  which  the  bones  are  left  covered  with  cartilage 
are  objectionable,  as  the  latter  has  almost  no  reparative  action.  The 
elliptical  method,  resembling  that  by  a  long  palmar  flap,  is  the  best.  In  it 
the  cicatrix  is  dorsal,  the  stump  is  covered  by  the  tough  and  well-nourished 
tissues  of  the  palm,  and  the  styloid  processes  are  well  covered.  The  great 
tendency  to  retraction  of  the  skin  on  the  dorsum,  due  to  the  looseness  of 
the  subcutaneous  tissues,  should  be  remembered.  Disarticulation  is 
easier  from  the  dorsum.  The  radial  artery  is  cut  at  the  outer  end  of  the 
dorsal  wound,  the  ulnar  at  the  inner  and  the  superficialis  voice  at  the 
outer  part  of  the  palmar  flap. 

Excision  of  the  Wrist. — Excision  of  the  wrist  includes  the  removal  of 
the  carpal  bones  and  usually  the  articular  ends  of  the  bones  of  the  forearm 
and  metacarpus.  As  the  joints  are  covered  and  protected  by  strong 
tendons  which  move  the  wrist  and  fingers  and  which  (save  those  of  the 
palmaris  longus  and  flexor  carpi  ulnaris)  are  surrounded  by  synovial 
sheaths,  the  incisions  are  planned  so  as  to  spare  these  tendons  and  their 
sheaths  as  far  as  possible.  Including  that  of  the  pisiform,  there  are  seven 
sepirate  synovial  sacs  in  the  joints  of  the  wrist  and  carpus.  It  is  important 
to  spare  the  radial  artery,  which  is  close  to  the  first  carpometacarpal 


THE  HAND  AND  FINGERS  215 

joint  (dorsally),  the  deep  palmar  arch  (see  p.  220),  and  if  possible  the 
annular  ligaments.  In  Oilier' s  method  the  dorsoradial  incision  is  along 
the  radial  border  of  the  extensor  indicis  tendon,  between  it  and  that  of 
the  extensor  longus  pollicis,  the  ulnar  incision  is  along  the  inner  side  of  the 
extensor  carpi  ulna ris  tendon.  The  pisiform  bone  may  usually  be  left,  and 
the  trapezium  should  be  when  possible.  Unless  the  subperiosteal  method 
is  employed,  and  this  is  often  difficult,  the  tendons  of  the  extensors  and 
flexors  of  the  carpus  are  severed  or  detached.  Another  simple  and  satis- 
factory method  is  to  split  the  hand  between  the  second  and  third  meta- 
carpal bones,  between  the  trapezoid  and  os  magnum,  and  between  the 
scaphoid  and  semilunar  bones,  by  an  incision  between  the  extensor  indicis 
and  the  extensor  communis  tendons.  Since  the  more  general  use  of  the 
./•-rays,  fracture  of  the  carpal  scaphoid  has  been  found  to  be  not  uncom- 
mon. The  fracture  passes  through  or  near  the  middle  third  of  the  bone 
and  the  central  fragment  is  not  infrequently  dislocated,  usually  backward. 
Stiffness,  with  abduction,  of  the  wrist  and  tenderness  in  the  tabatiere  are 
the  common  symptoms.    If  a  fragment  is  dislocated  it  should  be  removed. 

THE  HAND  AND  FINGERS. 

Surface  Markings  and  Landmarks. —Palmar  Surface. — Between  the 
thenar  eminence  on  the  radial  side  and  the  hypothenar  eminence  on  the 
ulnar  side  is  the  "hollow  of  the  hand,"  a  concavity  of  a  somewhat  tri- 
angular outline.  Its  apex  is  above  and  it  is  limited  below  by  three  little 
elevations  opposite  the  clefts  between  the  fingers.  These  elevations  are 
due  to  the  projection  of  the  fatty  tissue  between  the  flexor  tendons  and 
the  overlying  digital  slips  of  the  palmar  fascia,  which  form  the  grooves 
between  these  elevations.  The  hollow  of  the  hand  is  more  marked 
in  muscular  subjects  and  when  the  fingers  are  flexed  and  the  eminences 
adducted.  The  bony  prominences  at  the  proximal  ends  of  the  thenar 
and  hypothenar  eminences  have  already  been  referred  to. 

Three  of  the  many  creases  in  the  skin  of  the  palm  deserve  notice. 
The  first  marks  off  the  thenar  eminence  from  the  hollow  of  the  palm. 
It  starts  ;it  the  wrist  near  the  middle  line  and  ends  at  the  radial  border 
of  the  palm  at  the  base  of  the  first  phalanx  of  the  index  finger.  The  second 
-t;irt>  on  the  radial  border,  at  or  just  below  the  last,  and  crosses  the  palm 
obliquely  inward  and  upward  to  the  hypothenar  eminence.    The  third 

and   lowest  starts  from   the  elevation  Opposite  the  cleft   between  the  first 

and  second  fingers  and  rims  obliquely  inward  and  upward  to  the  ulnar 
border.    The  first  is  due  to  the  opposition  of  the  thumb,  the  second  to  the 

flexion  ;it  the  metacarpophalangeal  joint  of  the  index  and  middle  fingers, 
the  third  to  the  similar  flexion  of  the  inner  three  fingers.  Topographically, 
the  second  fold,  where  it  crosses  the  third  metacarpal  bone,  is  just  below 
the  lowest  point  of  the  superficial  palmar  arch,  and  the  third  fold  crosses 
the  necks  of  the  metacarpal  bones,  roughly  indicates  the  upper  limit  of  the 
synovial  sheath  of  the  middle  and  ring  ringers,  and  lies  a  little  above  die 
division  of  the  palmar  fascia  into  it.  digital  slips.  The  metacarpophalan- 
geal joints  lie  aboUl  midway  between  this  fold  ii  nd  the  ueb-  of  the  fingers. 


216 


THE  UPPER  EXTREMITY 


The  uppermost  of  the  folds  across  the  front  of  the  fingers  separate  them 
from  the  palm,  and  are  on  a  line  with  the  webs  of  the  fingers  and  12  to  15 
(^  in.)  below  the  metacarpophalangeal  joints.    The  upper  of  the 


mm. 


middle  series  of  folds  are  opposite  the  first  interphalangeal  joints  and  the 
lowest  set  of  folds  are  2  to  3  mm.  above  the  second  interphalangeal 
joints.  On  the  thumb  the  two  creases  correspond  to  the  two  joints,  the 
upper  crease  crossing  the  joint  obliquely. 


Fig.  80 


SUPERFICIAL^ 
PALMAR  ARCH 


DEEP 
PALMAR  ARCH 


ULNAR 
ARTERY 


RADIAL  ARTERY 


Position  of  the  principal  creases  of  the  palmar  surface  and  of  the  palmar  arches. 


Dorsal  Surface. — The  proximal  ends  of  the  first  and  fifth  metacarpal 
bones  are  prominent  and  can  be  readily  felt.  A  line  slightly  concave 
downward,  joining  the  upper  ends  of  these  and  1  cm.  (§  in.)  below  the 
lowest  skin  crease  in  front  of  the  wrist,  indicates  the  line  of  the  carpometa- 
carpal joints.  When  the  fingers  are  flexed,  the  prominences  of  the  knuckles 
are  formed  by  the  distal  ends  of  the  proximal  bone  of  each  joint  (Fig.  81), 
so  that  the  joint  line  lies  below  the  prominences  by  2  mm.  (y1^  in.)  in  the 
distal,  4  mm.  (^  in.)  in  the  middle,  and  8  mm.  (^  in.)  in  the  proximal 
joints.  The  first  dorsal  interosseous  muscle  forms  a  prominence  between 
the  first  and  second  metacarpal  bones  when  the  thumb  is  adducted. 


THE  HAND  AND  FINGERS 


217 


Fig.  81 


Outline  to  show  the  relation 
of  the  bent  knuckles  to  the 
joint  lines.  The  shaded  por- 
tions represent  the  epiphyses. 


The  Skin  of  the  Palm. — The  skin  of  the  palm  and  of  the  palmar  surface 
of  the  fingers  is  thick  and  dense  and  without  hairs  or  sebaceous  glands. 
Beneath  the  epidermis,  which  is  particularly  thick,  small  subepidermal 
abscesses  not  infrequently  develop.  Beneath  the  thinner  skin  of  the  distal 
phalanges  the  fibro-fatty  layer  forms  the  "pulp"  of  the  finger,  which  lies 
directly  upon  the  periosteum.  The  skin  of  the  dorsum  of  the  hand  is 
much  thinner,  and  down  to  the  second  or  third  phalanges  is  supplied  with 
numerous  hairs  and  sebaceous  follicles,  and  hence  is  liable  to  furuncles 
and  other  lesions  associated  with  these  structures.  The  skin  of  the  palm 
is  more  abundantly  supplied  with  sweat  glands 
than  any  other  part  of  the  body,  four  times 
more  so,  according  to  Sappey.  Hence  the 
profuse  perspiration  that  may  occur  here,  as  is 
well  known.  The  Pacinian  bodies  and  tactile 
corpuscles  in  connection  with  the  abundant 
cutaneous  nerve  supply  are  more  numerous  on 
the  palmar  aspect  of  the  fingers  than  elsewhere 
in  the  body.  The  palmar  aspect  of  the  third 
phalanx,  especially  that  of  the  index  finger,  is 
most  sensitive,  and,  with  the  exception  of  the 
tip  of  the  tongue,  possesses  more  acute  tactile 
sensibility  than  ony  other  part.     The  dorsum 

of  the  hand,  on  the  contrary,  has  but  little  tactile  sensibility.  The  area 
around  the  upper  end  of  the  nail  is  liable  to  superficial  subepidermal 
abscesses  ("run  around,"  paronychia),  which  develop  quickly.  The 
spaces  beneath  and  around  the  nail  and  the  various  glands  of  the  skin 
render  sterilization  of  the  hand  more  difficult  than  that  of  most  parts 
of  the  body. 

The  Subcutaneous  Tissue. — The  subcutaneous  tissue  on  the  palmar 
aspect  intimately  connects  the  overlying  skin  with  the  underlying  fascia 
in  the  palm,  and  with  the  tendon  sheaths  in  the  fingers.  Hence  subcu- 
taneous inflammatory  or  bloody  extravasations  and  edema  are  practically 
impossible  here,  while  on  the  dorsum,  where  the  subcutaneous  tissue  is 
lax  mid  abundant,  swelling  and  edema  may  be  very  marked.  For  the 
same  reason  skin  wounds  do  not  gape  on  the  palmar  surface,  but  gape 
widely  on  the  dorsum.    The  denseness  of  the  skin  and  underlying  tissues 

on  the  palm  renders  inflammation  very  painful  on  aeeounl  of  the  tension 

caused  by  the  inflammatory  products,  while  on  the  dorsum  the  reverse  is 
th<-  case.  Another  particular  in  which  the  coverings  of  the  /><dm  resemble 
ilir  sen//)  is  in  the  arrangement  of  the  subcutaneous  fat,  the  lobules  of 
which  are  contained  in  small  fibrous  compartments  of  the  subcutaneous 
This  arrangement  of  the  akin  and  underlying  tissues  of  the  palm 
adapts  it  f<>  resist  the  effects  of  pressure  mid  friction.  Thus  the  ulnar 
border  of  the  palm  is  much  used  in  resting  on  the  hand  and  in  hammering 
movements,  and  it  is  also  noteworthy  that  the  soft  pa rts  here  a  re  singula  il\ 
free  from  large  nerves.  The  entire  palmar  aspect  is  singularly  free  from 
large  surface  veins,  which  are  abundantly  found  on  the  dorsum  of  the 
hand.  Thelymph  vessels,  on  the  contrary,  are  more  numerous  on  the 
palmar  surface  of  the  band  and  fingers. 


218  THE  UPPER  EXTREMITY 

The  Palmar  Fascia. — The  palmar  fascia,  in  its  central  'portion  beneath 
the  hollow  of  the  palm,  is  very  dense  and  thick  and  is  triangular  in  form. 
Its  upper  end  is  connected  with  the  lower  border  of  the  annular  ligament 
and  receives  the  insertion  of  the  palmaris  longus,  of  which  it  is  sometimes 
regarded  as  the  degenerated  distal  end.  Its  lower  end  or  base  splits 
into  four  slips,  which  are  inserted  into  the  skin  at  the  bases  of  the  fingers 
and  send  fibers  to  the  fibrous  tendon  sheaths  of  the  fingers  and  the 
superficial  transverse  ligaments.  The  digital  vessels  and  nerves  and  the 
lumbricales  muscles  emerge  in  the  interval  between  these  slips.  The 
denseness  of  the  fascia  well  protects  the  soft  parts  beneath. 

Dupuytren's  contracture  is  a  peculiar  contraction  of  the  palmar  fascia 
and  its  slips,  especially  those  going  to  the  ring  and  little  fingers.  It  usually 
begins  about  opposite  the  metacarpophalangeal  articulation  and  extends 
in  both  directions.  It  occurs  especially  in  men  after  middle  life,  and  may 
be  associated  with  traumatism.  It  gradually  flexes  the  first,  then  the 
distal,  and  finally  the  second  phalanges  onto  the  palm.  The  tendons  are 
not  involved,  but  between  them  and  the  thickened  projecting  cord-like 
slips  of  fascia,  which  are  connected  with  and  wrinkle  the  skin,  is  a  layer 
of  fatty  connective  tissue. 

Laterally  the  palmar  fascia  is  continued  as  a  thinner  layer  over  the 
thenar  and  hypothenar  eminences.  A  fibrous  membrane  connects  the 
deep  surface  of  the  palmar  fascia,  on  each  side  of  the  central  portion,  with 
the  interosseous  fascia  covering  the  palmar  interossei.  In  this  way  two 
lateral  (thenar  and  hypothenar)  and  a  central  compartment  are  formed  in 
the  palm.  Suppuration  commencing  in  any  of  these  spaces  may  be 
limited  to  that  space  for  a  time,  but  the  membranous  septa  are  thin  and 
may  soon  yield.  The  central  compartment  is  continuous  above,  beneath 
the  annular  ligament  and  along  the  flexor  tendons,  with  the  wrist  and 
forearm.  It  is  continuous  below  with  the  sheaths  of  the  flexor  tendons  and 
the  three  intervals  between  the  digital  slips  of  the  fascia,  which  corre- 
spond to  the  webs  between  the  fingers.  Hence  pus  in  the  central  compart- 
ment of  the  palm  makes  its  way  up  into  the  forearm  or  down  along  or 
between  the  fingers.  The  resistance  offered  by  the  palmar  fascia  is  so 
firm  that  rather  than  perforate  it  pus  makes  its  way  through  the  inter- 
osseous spaces  to  the  dorsum,  though  this  course  is  resisted  by  a  layer 
of  fascia  covering  the  deep  palmar  arch  and  the  interossei  muscles. 
This  deep  fascia  joins  the  membranous  septa  separating  the  central 
compartment  of  the  palm  from  the  thenar  and  hypothenar  compartments 
in  front  of  the  third  and  fourth  metacarpal  bones  respectively. 

Practically  abscesses  of  the  palm  may  be  divided  into  those  in  front  of 
and  those  behind  the  palmar  fascia.  Abscesses  in  front  of  the  fascia, 
whether  subepithelial  or  subcutaneous,  are  small,  confined  to  the  palm, 
and  very  painful;  but  the  pain  is  limited  to  the  palm,  movement  of  the 
fingers  is  not  very  painful,  and  there  is  no  tendency  to  extend  to  the 
wrist  or  to  cause  swelling  of  the  dorsum  unless  it  occurs  in  the  areas  just 
above  the  interdigital  clefts.  Subfascial  infection  or  abscess  may  spread 
to  the  fingers,  wrist,  and  forearm  by  following  the  flexor  tendons,  or  to  the 
dorsum  after  perforating  the  interosseous  fascia.    The  dorsum  is  usually 


PLATE  XXII 


FIG.  82 


r — MEDIAN     NERVE 

A     SHEATH    OF    FLEXOR 


ULNAR    NERVE 


PALMAR    SHEATH    OF 
FLEXOR    TENDONS 
OF    FINGERS 

TENDON    OF    FLEX.      \ 
SUBL.     DIGIT. 


tendon  of  flex 
prof.   d:g;t 


ARPI     RAOIALIS 


SHEATH    OF 
FLEXOR 

LONGUS 
POLLICIS 


DIGITAL    SHEATH 
OF    LONG    FLEX. 

TENDONS 


Tendon  Sheaths  and  Muscles  or  the  Palmar  Surface  of  the 
Left  Hand.     (Joessel.) 


THE  HAND  AND  FINGERS  219 

much  swollen.  Pointing  of  such  abscesses  may  also  occur  just  at  or  above 
the  clefts  of  the  fingers.  The  pain  is  intense,  is  felt  along  the  course  of  the 
nerves,  and  is  increased  by  movements  of  the  fingers.  In  opening  abscesses 
of  the  palm  and  in  all  operations  on  the  palm  the  incision  should  be  ver- 
tical, parallel  with  the  tendons  and  digital  nerves,  and  above  or  below  the 
superficial  palmar  arch  (see  p.  197).  If  an  incision  is  required  in  the 
wrist  it  should  be  vertical,  and  if  made  on  the  ulnar  side  of  the  palmaris 
longus  tendon  it  will  avoid  the  ulnar  and  radial  arteries  and  the  median 
nerve. 

The  fibrous  sheaths  of  the  flexor  tendons  extend  from  the  metacarpo- 
phalangeal joints  to  the  upper  ends  of  the  last  phalanges  at  the  insertion 
of  the  flexor  profundus  tendons.  There  being  no  intervening  fascia  in 
the  fingers,  the  skin  and  subcutaneous  tissues  are  connected  with  these 
sheaths  in  the  same  intimate  way  as  with  the  fascia  in  the  palm.  The 
fibrous  sheaths  arch  across  the  front  of  the  phalanges  between  their 
lateral  margins  and  thus  form  semicvlindrical  canals  which  lodge  the 
synovial  sheaths.  The  fibrous  sheaths  are  dense  and  rigid,  so  as  to  remain 
open  when  cut,  so  that  in  amputation  of  the  fingers  an  open  channel, 
leading  up  to  the  palm,  is  left  for  the  spread  of  infection.  Opposite  the 
joints  of  the  fingers  the  sheaths  are  thin  and  lax,  leaving  spaces  between 
their  obliquely  decussating  fibers,  through  which  the  synovial  lining  may 
protrude  and  suppuration  may  find  its  way  into  the  interior  of  the  sheath. 

Synovial  Sheaths. — Two  synovial  tendon  sheaths  are  found  in  the  palm, 
the  outer  for  the  flexor  longus  pollicis,  the  inner  for  the  superficial  and 
deep  flexors  of  the  fingers.  These  extend  up  beneath  the  annular  liga- 
ment, where  they  are  constricted,  and  for  about  3  cm.  (lj-  in.)  above  it 
into  the  wrist.  Inferiorly  the  outer  one  extends  to  the  insertion  of  the 
flexor  longus  pollicis,  the  inner  one  to  the  insertion  of  the  flexor  profundus 
of  the  little  finger,  and  to  about  the  middle  of  the  metacarpal  bone  for  the 
other  three  fingers,  but  farther  down  on  the  tendons  of  the  ring  finger 
than  on  those  of  the  other  two.  On  the  ring,  middle,  and  index  fingers  the 
digital  synovial  sheaths  commence  opposite  the  heads  of  the  metacarpal 

bones  and  extend  to  the  insertion  of  the  profundus  tendons,  being  con- 
tained within  the  fibrous  sheath  ( Fig.  82).  They  are  thus  separated  by 
12  to  25  nun.  (\  to  1   in.)  from   the  main  palmar  synovial  sheath  of  the 

flexor  tendons.    Hence  operations  on  and  inflammation  of  the  thumb 

and  little  finger  are  more  serious  than  of  the  other  fingers,  for  inflamma- 
tion in  the  former  may  more  readily  spread  to  the  main  synovial  sacs, 
Causing  a  swelling  of  the  palm,  which  is  constricted  beneath  the  annular 

ligament  and  is  expanded  again  in  front  of  the  wrist,  "hour-glass  shape." 

Thi~  i      seen,  not   infrequently,  in  case  of  felon  of   these  two  fingers.      As 

the  two  ,,;ks  may  communicate  normally  or  pathologically,  inflammation 

may  spread  from  the  thumb  to  the  little  finger,  or  vice  versa,  giving  rise 

to  a  horseshoe^haped  swelling.  The  two  palmar  sacs  may  be  the  seat 
of  cysts  which  show  their  characteristic  form.  In  case  "I  tuberculous 
inflammation  here,  and  in  the  sheaths  of  the  extensor  tendons  al  the  back 

of  the  writ,  the  sheaths  are  often  filled  with  fibrinous  masses  known  as 

rice  bodies.    The  tendons  within  their  synovial  sheath    do  not  lie  \H-\-, 


220  THE  UPPER  EXTREMITY 

but  are  connected  with  them  by  synovial  folds,  like  mesenteries,  which 
contain  the  nutrient  vessels  and  may  be  ruptured  in  severe  sprains, 
causing  an  effusion  in  the  sac.  In  the  digital  sheaths  these  folds  are 
almost  wanting. 

The  Superficial  Palmar  Arch  (Figs.  76,  80). —  The  superficial  palmar 
arch  lies  beneath  the  palmar  fascia  and  superficial  to  the  flexor  tendons. 
Its  course  is  represented  by  a  line,  slightly  convex  downward,  commenc- 
ing at  the  radial  side  of  the  pisiform  bone  and  crossing  the  palm  in  line 
with  the  palmar  aspect  of  the  thumb  when  abducted  at  right  angles  with 
the  index  finger.  This  line  should  be  avoided  if  possible  in  incisions  in  the 
palm.  The  deep  arch  (Fig.  80)  lies  about  12  mm.  (|-  in.)  nearer  the  wrist, 
in  front  of  the  bases  of  the  metacarpal  bones,  and  beneath  the  deep  or 
interosseous  fascia.  It  is  nearer  the  dorsal  than  the  palmar  surface  and 
is  more  liable  to  injury  from  the  former  side.  The  bifurcation  of  the 
digital  arteries  occurs  about  12  mm.  (^  in.)  above  the  webs  of  the  fingers. 

The  blood  supply  of  the  fingers  is  very  abundant,  the  pulp  of  the  fingers 
being  one  of  the  most  vascular  parts  of  the  body.  It  is  owing  to  this  fact 
that  in  so  many  cases  the  tip  of  the  finger,  accidentally  cut  off,  has  grown 
on  again  when  reapplied  at  once. 

Wounds  of  the  palmar  arches  and  their  branches  are  serious  on  account 
of  the  difficulty  of  checking  the  hemorrhage.  This  is  due  to  the  danger  of 
damaging  important  structures  of  the  palm  and  to  the  free  anastomoses, 
whereby  ligature  of  either  the  radial  or  ulnar  or  both  does  not  control 
the  bleeding,  for  the  arches  anastomose  with  each  other  and  with  the 
carpal  arches,  which  communicate  with  the  two  interosseous  vessels 
above.  Hence  the  two  ends  of  the  divided  artery  should  be  secured  if 
possible,  but  if  the  wound  is  deep  or  narrow,  pressure  may  often  arrest 
the  bleeding.  The  possibility  that  pressure  may  cause  gangrene,  owing 
to  the  rigidity  of  the  parts,  should  be  borne  in  mind. 

Beneath  the  superficial  arch  and  superficial  to  the  flexor  tendons  is 
the  median  nerve  in  the  groove  between  the  long  flexor  of  the  thumb 
and  the  flexors  of  the  fingers  (Figs.  76,  82).  The  nerve  supply  of  the 
hand  and  fingers  is  of  interest  and  practical  importance. 

Cutaneous  Nerve  Supply  (Figs.  83  and  84). — Palmar  Surface. — The 
palm  is  supplied  by  the  median  and  ulnar  nerves  which  anastomose  with 
one  another.  The  palmar  aspect  of  the  little  finger  and  the  ulnar  side  of 
the  ring  finger  are  supplied  by  the  ulnar,  that  of  the  other  fingers  by  the 
median.  On  the  dorsum  of  the  hand  the  radial  and  ulnar  nerves  supply 
its  radial  and  ulnar  sides  respectively,  and  anastomose  with  one  another. 
The  dorsal  aspect  of  the  thumb  is  supplied  by  the  radial  nerve,  as  is  that 
of  the  index  and  the  radial  side  of  the  middle  finger,  as  far  as  the  second 
phalanx.  The  dorsal  branch  of  the  ulnar  nerve  supplies  the  dorsal 
aspect  of  the  little,  ring,  and  ulnar  side  of  the  middle  fingers  as  far  as  the 
second  phalanx.  In  some  cases  the  contiguous  halves  of  the  dorsum  of 
the  first  phalanx  of  the  ring  and  middle  finger  is  supplied  by  the  radial 
nerve  or  partly  by  the  radial  and  partly  by  the  ulnar.  The  dorsal  aspect 
of  the  second  and  third  phalanges  of  the  four  fingers  are  supplied  by 
branches  from  the  nerves  supplying  their  palmar  surfaces. 


THE  HAND  AND  FINGERS 
Fig.  83 


221 


ipply  .,f  the  uppei  limb,  ■..-., n-.i  i  peel      l  W    Kelller.) 


222  THE  UPPER  EXTREMITY 

The  occasional  apparently  contradictory  results  of  nerve  lesions  are 
partly  due  to  the  above-mentioned  variation  (on  the  ring  and  middle 
fingers)  and  to  the  anastomoses  between  the  nerves  on  the  dorsal  and 
palmar  surfaces  of  the  hand.  Thus  the  loss  of  sensation  is  often  quite 
slight  in  comparison  with  the  area  supplied,  and  the  same  facts,  and  not 
"immediate  union,"  probably  help  to  explain  the  cases  where  sensation 
has  returned  within  a  few  hours  after  suture  of  one  of  the  nerves. 

Motor  Nerve  Supply. — The  ulnar  nerve  supplies  the  interossei,  adductor 
pollicis,  inner  head  of  the  flexor  brevis  pollicis,  and  the  two  inner  lum- 
bricales,  as  well  as  the  muscles  of  the  hypothenar  eminence  and  the  inner 
half  of  the  flexor  profundus.  Hence  paralysis  of  the  ulnar  is  followed  by 
inability  to  adduct  the  thumb  (adductor),  to  flex  the  last  phalanx  (pro- 
fundus) of  the  two  inner  fingers,  or  to  flex  the  first  (interossei)  or  extend 
the  last  two  phalanges  (interossei)  of  all  the  fingers.  Hence  the  hand  is 
held  with  the  first  phalanges  extended  and  the  other  phalanges  (except 
the  terminal  phalanges  of  the  two  inner  fingers)  flexed,  giving  the  position 
known  as  "claw  hand."  Abduction  and  adduction  of  the  fingers  is 
interfered  with,  owing  to  paralysis  of  the  interossei.  The  muscles  of  the 
hypothenar  and  ulnar  part  of  the  thenar  eminences  are  paralyzed  and 
become  atrophied. 

As  the  median  nerve  supplies  the  rest  of  the  long  flexors  and  those 
thumb  muscles  not  supplied  by  the  ulnar,  and  also  the  two  outer  lum- 
bricales,  its  paralysis  is  followed  by  inability  to  flex  the  second  phalanx 
of  all  fingers,  the  last  phalanx  of  the  middle  and  index  fingers,  to  flex 
or  abduct  the  thumb,  to  pronate  the  hand,  and  to  flex  the  wrist,  except 
by  means  of  the  flexor  carpi  ulnaris.  The  thumb  is  held  adducted  and 
extended.  After  the  last  phalanges  of  the  two  inner  fingers  is  flexed, 
continued  action  of  their  flexor  profundus  tendons  will  flex  the  second 
phalanges.  Flexion  of  the  first  phalanges  with  extension  of  the  last  two 
can  be  performed  in  all  fingers  by  means  of  the  interossei.  Except  as  the 
result  of  wounds  of  the  axilla  or  wrist  isolated  paralysis  of  the  median 
nerve  is  rare. 

On  the  dorsum  of  the  hand  the  extensor  tendons  are  united  together 
by  connecting  slips  (Fig.  77) ,  so  that  it  is  difficult  to  extend  one  without 
the  neighboring  finger.  The  index  finger  can  be  extended  alone  most 
readily,  next  the  little  finger,  for  they  are  joined  by  only  one  band  to  the 
tendon  of  the  neighboring  finger.  The  ring  finger  is  extended  alone  with 
the  most  difficulty.  The  extensor  tendons  serve  the  place  of  posterior 
ligaments  for  the  three  joints  of  the  fingers.  When  the  last  two  phalanges 
alone  are  flexed,  the  first  is  steadied  by  the  extensor  tendons,  so  that 
in  paralysis  of  the  latter  this  movement  is  not  possible.  When  a  finger 
is  torn  out  it  takes  with  it  one  or  more  tendons,  most  often  the  flexor 
profundus  tendon  if  only  one  is  avulsed. 

Felon  or  whitlow  is  an  inflammation  usually  commencing  on  the  palmar 
aspect  of  the  terminal  phalanx,  in  the  soft  parts,  tendon  sheaths,  or  peri- 
osteum. However  it  begins,  unless  it  is  promptly  incised,  it  is  liable  to 
extend  to  the  synovial  sheath  of  the  tendon  or  to  the  periosteum.  The 
latter  is  readily  attacked  as  it  is  not  covered  by  the  tendon  sheath  beyond 


THE  HAND  AND  FINGERS 


l>l';; 


Fig.  84 


Cutana  apply  of  the  upper  limb,  doml  •  pecti     (W,  Keillei  I 


224  THE  UPPER  EXTREMITY 

the  base  of  the  terminal  phalanx.  As  the  result  of  the  involvement  of 
the  periosteum,  the  bone  often  necroses,  but  usually  only  the  terminal 
part,  for  the  base,  which  is  an  epiphysis  not  uniting  with  the  shaft  until 
about  the  eighteenth  year,  is  protected  by  the  insertion  of  the  flexor 
profundus  tendon,  probably  by  keeping  up  its  blood  supply.  Owing 
to  the  absence  of  the  tendon  sheath  over  the  distal  phalanx,  except  at  its 
base,  the  infection  is  not  so  likely  to  extend  to  the  sheath  unless  it  involves 
the  middle  or  proximal  phalanges.  When  the  synovial  sac  is  involved 
the  inflammation  extends  to  the  end  of  the  sac,  opposite  the  head  of  the 
metacarpal  bone,  except  in  case  of  the  thumb  or  little  finger,  in  which  it 
may  extend  into  the  palm,  beneath  the  annular  ligament  and  up  into  the 
wrist,  etc.  (see  p.  218-19). 

Bones  and  Joints. — In  fracture  of  the  metacarpal  bones  but  little  dis- 
placement is  allowed,  as  they  are  splinted  to  the  neighboring  bones  by  the 
interosseous  muscles  and  the  transverse  ligaments.  The  carpometacarpal 
joints  of  the  first  three  fingers  allow  of  but  little  motion,  that  of  the  little 
finger  and  especially  that  of  the  thumb  allow  more  free  motion.  The 
preservation  of  these  joints  is  of  great  importance  to  the  usefulness  of 
the  hand.  Under  all  circumstances  as  much  of  the  thumb  as  possible 
and  a  portion  of  the  fingers  or  hand,  to  oppose  it,  should  be  saved,  to 
preserve  the  forceps  or  grasping  function  of  the  hand. 

Dislocations  of  the  metacarpophalangeal  and  interphalangeal 
joints  are  common.  Dislocation  of  the  first  phalanx  of  the  thumb  backward 
is  the  most  common  and  the  most  important  on  account  of  its  common 
occurrence  and  the  frequent  difficulty  in  its  reduction.  The  condylar 
head  of  the  metacarpal  bone  is  most  prominent  on  its  outer  side.  The 
tendon  of  the  long  flexor  muscle  lies  nearer  the  inner  than  the  outer  side. 
Its  containing  sheath  extends  up  to  and  is  connected  with  the  glenoid 
ligament.  The  short  muscles  of  the  thumb  are  relaxed  by  pressing  the 
metacarpal  bone  into  the  palm  (adduction).  The  extensors  and  long 
flexors  are  relaxed  by  slight  abduction  of  the  wrist.  As  the  attitude  of 
dislocation  (hyperextension)  is  maintained  by  the  tension  of  the  short 
muscles  attached  to  the  thumb,  these  two  movements,  relaxing  as  much 
as  possible  the  muscles  attached  to  the  thumb,  favor  the  reduction  of  a 
dislocation.  The  difficulty  in  reduction  has  been  explained  in  many  ways : 
the  buttonholing  of  the  head  of  the  metacarpal  bone  between  the  two 
sets  of  muscles  which  centre  in  the  sesamoid  bones,  the  entanglement  of 
the  long  flexor  tendon  around  the  inner  side  of  the  neck  of  the  metacarpal 
bone,  the  intervention  of  the  anterior  glenoid  ligament  between  the  two 
joint  surfaces,  etc.  The  latter  explanation  is  thought  by  Faraboeuf  to 
cover  most  cases.  The  glenoid  ligament  is  torn  from  the  metacarpal 
bone,  to  which  it  is  loosely  attached,  but  remains  fixed  to  the  phalanx  and 
is  carried  back  with  it.  If  now  the  thumb  is  straightened,  as  it  may  be, 
and  traction  is  made  in  this  position,  the  muscles  attached  to  the  sesa- 
moid bones,  which  are  attached  to  the  ligament,  pull  the  latter  back,  and 
if  the  phalanx  is  brought  into  place  by  this  traction,  the  glenoid  ligament 
lies  between  the  joint  surfaces  with  its  anterior  face  applied  to  the  head  of 
the  metacarpal  bone.     In  any  case  traction  in  the  straightened  position 


THE  HAND  AND  FINGERS  225 

should  never  be  employed  in  reduction  for  fear  of  changing  a  simple  into  a 
"complex  dislocation,"  but  rather  traction  in  the  hyperextended  position 
followed  by  flexion.  According  to  Stimson,  the  resistance  to  reduction  is 
due  to  the  torn  edges  of  the  anterior  ligament  drawn  closely  about  the 
metacarpal  bone  behind  its  head.  This  condition  is  frequently  found  on 
arthrotomy,  performed  to  reduce  the  dislocation,  and  a  slight  nicking  of 
the  tense  edge  makes  reduction  easy. 

As  it  is  important  to  know  from  which  spinal  nerves  and  segments  the 
various  nerves  of  the  arm  spring  and  the  muscles  supplied  by  them  are 
innervated,  for  the  purpose  of  diagnosis  of  nerve  injuries  of  the  upper 
limb,  the  following  table  is  added: 

Nerves. — Suprascapular  and  circumflex  nerves,  5,  6,  C;  posterior 
thoracic  (nerve  of  Bell)  and  musculocutaneous,  5,  6,  7,  C;  internal 
cutaneous  and  ulnar,  8,  C.,  and  1,  D.;  lesser  internal  cutaneous  (nerve  of 
Wrisberg),  1,  D.;  musculospiral,  5,  6,  7,  8,  C;  median,  6,  7,  8,  C,  and 
1,  D.;  nerve  to  rhomboids,  5,  C;  nerves  to  subscapulars  and  teres  major 
(upper  and  lower  subscapular),  5,  6,  C;  nerve  to  latissimus  dorsi  (middle 
or  long  subscapular),  6,  7,  8,  C. 

The  entire  brachial  plexus  may  be  ruptured  or  torn  away  from  its 
attachments  to  the  cord,  or  one  or  more  of  its  cords,  primary  divisions  or 
branches  may  be  torn,  stretched,  or  compressed.  The  common  cause 
of  rupture  of  one  or  more  cords  of  the  brachial  plexus  is  the  violent  abduc- 
tion of  the  head  from  the  shoulder,  and  a  common  example  of  this  is  seen 
in  brachial  birth  palsy,  in  which  this  abduction  occurs  during  delivery. 
The  upper  cords  or  roots  are  first  and  most  often  involved  in  brachial 
palsy.  The  cutaneous  distribution  of  the  nerves  of  the  arm  is  shown  in 
Figs.  83,  84. 


CHAPTEE  III. 

THE  THORAX. 
THE  THORACIC  WALLS. 

Shape  and  Size. — The  adult  thorax,  covered  by  the  soft  parts,  appears 
conical,  with  its  base  above  and  its  apex  below,  and  flattened  from  before 
backward.  Its  circumference  at  the  apex  of  the  axilla  is  considerably 
greater  in  the  male  than  that  at  the  level  of  the  nipple  or  at  the  base  of  the 
xiphoid  process.  In  the  female  the  circumference  at  the  nipple  is  nearly 
as  great  as  that  at  the  axilla  and  the  latter  is  considerably  less  than  the 
similar  measurement  in  the  male.  In  the  'phthisical  the  upper  circum- 
ference is  less  than  the  lower  (Hirtz).  The  senile  thorax  is  narrowed 
above  and  lengthened  so  as  to  be  conical  with  the  base  below.  This  is 
due  to  a  sinking  of  the  front  of  the  ribs,  due  to  the  relaxed  tone  of  the 
muscles.  In  the  fetus  it  is  flattened  laterally,  the  anteroposterior  diameter 
being  the  greater.  In  the  infant  at  birth  the  thorax  is  short,  nearly  circular 
on  cross-section,  and  conical,  with  its  base  below.  These  differences  in  the 
infant  are  due,  respectively,  to  the  more  horizontal  position  of  the  ribs, 
the  absence  of  the  angles  of  the  ribs,  and  the  greater  size  of  the  liver,  as 
compared  with  the  lungs. 

The  length  of  the  posterior  wall  is  over  twice  that  of  the  anterior  wall 
in  the  median  line  (31.5  cm.  to  15.5  cm.)  and  the  length  of  the  side  of  the 
thorax  is  greater  than  that  of  the  posterior  wall.  The  height  of  the  thorax 
increases  with  that  of  the  body,  but  not  proportionally,  the  transverse 
diameter  increases  less  and  the  anteroposterior  diameter  still  less.  The 
greater  height  of  the  body  is  largely  due  to  the  length  of  the  lower 
extremities.  However,  a  too  small  circumference  of  the  thorax  in  a  tall 
subject  is  thought  to  indicate  a  predisposition  to  phthisis.  In  the  Prus- 
sian army  those  whose  chest  circumference  is  less  than  half  the  body 
height  are  regarded  as  narrow-chested  and  predisposed  to  tuberculosis, 
unless  the  chest  is  widened  by  drill.  The  thorax  of  the  female  is 
relatively  smaller  than  that  of  the  male,  is  less  flattened,  and  more 
rounded.  The  tivo  halves  of  the  thorax  are  usually  unsymmetrical,  the 
right  measuring  more  (1  to  1|  cm.),  owing  to  the  greater  use  of  the  right 
side. 

When  the  soft  parts  covering  it  have  been  removed,  the  thorax  is 
seen  to  be  conical  in  shape  with  the  apex  above.  Hence  the  lung  capacity 
is  not  indicated  by  the  breadth  of  the  shoulders,  but  rather  by  the  size 
of  the  base  of  the  neck. 

Abnormal  and  Pathological  Forms  of  the  Thorax. — Occupation 
may  affect  the  shape,  as  by  the  pressure  of  tools  depressing  the  ster- 


THE  THORACIC    WALLS 


007 


quid  and  flattening  the  thorax.  Corsets  may  so  press  in  the  lower  ribs 
as  to  make  the  thorax  spindle-shaped,  or  even  smaller  below  than  above. 
In  pigeon  breast  the  sternum  and  eostal  cartilages  are  protruded  in 
relation  to  the  ribs,  like  the  sternum  of  a  bird,  and  the  sides  of  the  chest 
are  flattened.  It  occurs  especially  in  rickety  children,  in  whom  the  long- 
bones  are  not  properly  ossified,  particularly  at  their  epiphyseal  junctions, 
as  at  the  costochondral.  In  such  a  case  there  is  often  obstruction  in  the 
respiratory  passages,  due  to  adenoids  or  hypertrophied  tonsils,  so  that  in 
inspiration  the  air  cannot  enter  the  chest  fast  enough  to  make  the  air 
pressure  within  equal  to  the  atmospheric  pressure  without  the  thorax. 
Hence  the  weakest  part,  or  that  along  the  costochondral  line,  is  pressed 

Fig.  85 


Outlines  of  I,  normal  chest;    II,  emphysematous  cheat;    III,  pigeon  breasted  chest;    IV,  Sat 
or  tuberculous  chest;   V,  scoliotic  oblique  chest.      Diagrammatic. 


inward,  becoming  a  deep  groove  and  making  the  sternum  relatively 
prominent.    In  rickets  da-  enlargements  of  die  cuds  of  the  ribs  along  this 

line  is  often  palpable  and  sometimes  visible,  receiving  the  name  of  headed 
ribs,  or,  if  numerous  and  bilateral,  "rickety  rosary." 

Two  opposite  pathological  types  of  thorax  may  be  distinguished. 
The  emphysematous  type  or  //"■  type  of 'permanent  inspiration  is  like  thai 
Been  in  pulmonary  emphysema.  The  chest  is  barrel-shaped,  enlarged 
in  circumference  but  shortened  vertically.     As  it  is  in  (he  position  of 

inspiration    at    all    times,    the     capacity    of     the    chest    cannot    be    much 

increased.  The  upper  pari  is  chiefly  affected.  An  approach  to  this  type 
i^  normal  as  adult  life  advances.  The  type  of  permanent  expiration  or  the 
phthisical  type  (habitus  paralyticus)  is  the  opposite  of  the  above.  The 
die  i  appears  flattened  and  lengthened.  It  may  predispose  to  phthisis 
or  be  (hi-  result  of  it.  The  upper  pari  of  the  thorax  is  especially  con- 
tracted. 


228  THE  THORAX 

Again,  in  posterior  and  lateral  curvatures  of  the  thoracic  spine  the  thorax 
is  deformed.  In  posterior  curvature  of  the  spine  (usually  the  result  of 
Pott's  disease)  the  sternum  is  thrust  forward  and  the  ribs  are  more 
oblique,  approaching  the  pelvis  so  that  the  free  ribs  overlap  the  iliac 
crests.  In  lateral  curvature  the  ribs  on  the  convex  side  of  the  curve  are 
more  separated  from  one  another  than  normal,  those  on  the  concave  side 
more  pressed  together  and  sometimes  so  depressed  as  to  touch  or  even 
overlap  the  iliac  crests.  Owing  to  the  rotation  of  the  vertebrae  the  ribs 
on  the  convex  side  bulge  posteriorly  on  account  of  the  prominence  of 
their  angles,  and  the  scapula  is  carried  back  with  them,  making  a  "hump" 
on  that  side.  On  the  concave  side,  usually  the  left,  the  front  of  the  chest 
is  abnormally  prominent.  As  a  result  of  pleuritic  or  pericardial  effusions, 
aneurysm,  tumors,  etc.,  the  thorax  may  become  protruded  and  it  may 
become  sunken  in  from  retraction  of  an  adherent  lung,  etc.  Such  pro- 
trusions and  retractions  may  involve  a  part  or  the  whole  of  one  or  both 
halves  of  the  thorax. 

The  Internal  Configuration. — The  internal  configuration  of  the  thorax 
is  somewhat  heart-shaped,  owing  to  the  forward  projection  of  the  verte- 
bral bodies,  which  renders  the  internal  sagittal  diameter  but  1  cm.  more 
than  one-half  the  same  measurement  externally.  Owing  to  the  backward 
projection  of  the  angles  of  the  ribs  and  the  fact  that  the  line  of  gravity 
descends  in  the  cord  of  the  backward  curve  of  the  thoracic  vertebrae 
there  is  nearly  as  much  space  within  the  thorax  behind  the  line  of  gravity 
as  there  is  in  front  of  it.  Hence  the  erect  position  is  easily  maintained 
without  the  excessive  muscular  action  which  is  necessary  in  animals,  in 
which  these  conditions  do  not  prevail.  Furthermore,  in  the  human 
subject,  the  backward  projection  of  the  angles  of  the  ribs  on  either  side  to 
about  the  level  of  the  vertebral  spines  renders  possible  the  supine  posi- 
tion, which  is  not  possible  in  animals,  as  in  them  the  spines  project 
mesially  without  the  corresponding  lateral  projection  of  the  ribs. 

Boundaries  of  the  Thorax. — The  thorax  is  bounded  in  front  by  the 
sternum,  costal  cartilages  and  the  spaces  between  them,  laterally  by  the 
ribs  and  intercostal  spaces,  behind  by  the  thoracic  vertebrae  and  the  pos- 
terior ends  of  the  ribs  and  intercostal  spaces.  The  bony  thorax  covers 
several  of  the  abdominal  viscera  in  addition  to  the  thoracic,  hence, 
besides  the  thoracic  cavity  proper,  it  bounds  part  of  the  abdominal 
cavity,  the  two  being  separated  by  the  obliquely  placed  diaphragm  (see 
p.  239).  The  latter,  therefore,  forms  the  convex  floor  of  the  thoracic 
cavity  proper.  The  apices  of  the  lungs  and  the  domes  of  the  pleural 
cavities  extend  through  the  small  superior  aperture  of  the  thorax,  as  well 
as  the  trachea  and  esophagus  and  the  vessels,  nerves,  and  muscles  which 
pass  between  the  neck  and  the  thoracic  cavity.  This  superior  aperture 
connects  the  neck  and  the  thoracic  cavity.  It  is  formed  by  the  first  ribs, 
first  thoracic  vertebra,  and  the  top  of  the  sternum,  is  kidney-shaped,  and 
slanted  slightly  downward  from  behind  forward.  It  measures  5.5  cm. 
(2\  in.)  from  behind  forward  and  10.5  cm.  (4£  in.)  transversely. 

To  assist  in  the  topography  of  the  chest  we  distinguish  certain 
vertical  lines  in  addition  to  the  median  or  midsternal  line,  i.  e.,  the  sternal 


THE  THORACIC  WALLS  229 

line  along  the  side  of  the  sternum,  the  mammary  line  through  the  nipple, 
the  midclavicular  line  through  the  middle  of  the  clavicle,  practically 
identical  with  the  mammary  line,  the  axillary  line  midway  between  the 
the  anterior  and  posterior  axillary  lines,  which  are  drawn  through  the 
lower  ends  of  the  anterior  and  posterior  axillary  folds,  and  the  scapular 
line  drawn  through  the  inferior  angle  of  the  scapula.  The  parasternal 
line  is  midway  between  the  sternal  and  mammary  lines  and  the  costo- 
clavicular line  connects  the  sternoclavicular  joint  with  the  tip  of  the 
eleventh  rib  on  the  same  side. 

Landmarks  of  the  Thoracic  Walls.— In  the  median  line  anteriorly  the 
top  of  the  sternum  corresponds  to  the  cartilage  between  the  second  and 
third  thoracic  vertebrae;  the  junction  of  the  manubrium  and  body  of  the 
sternum  is  indicated  by  a  readily  palpable,  prominent,  transverse  ridge 
(angulus  Ludovici),  which  is  continuous  with  the  second  costal  cartilages. 
This  is  the  easiest  and  most  reliable  point  to  start  from  in  counting  the 
ribs.  It  corresponds  to  the  disk  between  the  fourth  and  fifth  thoracic 
vertebrae.  The  junction  of  the  body  and  ensiform  process  of  the  sternum 
is  readily  palpable  as  a  ridge,  for  the  ensiform  is  at  a  deeper  level  than 
the  sternal  body.  This  junction  corresponds  to  the  articulation  of  the 
seventh  costal  cartilage  with  the  sternum,  and  to  the  lower  part  of  the 
ninth  thoracic  vertebra  behind.  It  is  also  on  a  level  with  the  lowest 
point  of  the  fifth  rib. 

Laterally  the  nipple  lies  on  a  level  with  the  anterior  end  of  the  fourth 
rib  (Hyrtl)/  or  in  the  fourth  space,  nearly  2.5  cm.  (1  in.)  external  to  the 
costal  cartilage  and  vertically  in  line  with  the  middle  of  the  clavicle.  The 
virgin  breast  covers  the  ribs  from  the  third  to  the  sixth.  The  lowest 
point  of  the  seventh  rib  (the  junction  of  the  rib  and  costal  cartilage)  lies 
in  the  mammary  line.  The  costochondral  junction  of  the  ribs  above  the 
seventh  lie  internal  to  this  line,  that  of  the  lower  ribs  external  to  this 
line,  in  an  oblique  line  extending  downward  and  outward.  The  lower 
border  of  the  peetoralis  major  corresponds  to  the  fifth  rib,  the  first 
visible  serration  of  the  serratus  magnus  to  the  fifth  rib,  the  largest  ser- 
ration to  the  sixth  rib.  Posteriorly  the  scapula  covers  the  ribs  from  the 
second  to  the  seventh  (sometimes  the  eighth).  Hence  the  first  interspace 
below  the  scapula  is  the  seventh  (sometimes  the  eighth).  Owing  to  the 
obliquity  of  the  ribs  we  find  in  a  sagittal  section  in  the  mammary  line  th;il 
the  first  rib  in  front  corresponds  to  the  fourth  rib  behind,  the  second  to  the 
sixth,  the  third  to  the  seventh,  etc.,  each  rib  below  the  first  in  front  corre- 
sponding to  the  fourth  one  lower  in  the  scries  behind. 

The  Layers  of  the  Thoracic  Wall.  The  Skin  over  the  Sternum.  The 
skin  over  the  sternum  is  a  favorite  locality  for  keloid  growths.  Gummata 
also  are  often  found  in  the  soft  parts  covering  the  sternum,  especially 
the  periosteum.    The  subcutaneous  tissue  of  the  thoracic  wall  may  be  the 

seat  of  extensive  em pli y.srnia  in  some  fractures  of  the  ribs  or  in  perfor- 
ating wounds  of  the  thorax. 

The  Sternum.  The  sternum  is  very  variable  in  length  and  is  often  not 
in  proportion  to  the  height  of  the  body.  I  have  seen  the  sternum  26  cm. 
(10!  in.) long  in  ;<  man  of  average  height.     In  women  the  sternum, and 


230  THE  THORAX 

especially  its  body,  is  relatively  shorter  than  in  men.  The  holes  or  clefts 
in  the  lower  part  of  the  sternum,  due  to  defects  in  its  development  from 
two  lateral  halves,  may  afford  pus  an  entrance  to  or  an  exit  from  the 
mediastinum.  After  a  median  division  of  the  sternum  the  two  halves 
may  be  retracted  so  as  to  expose  for  ligation  the  great  vessels  in  the 
mediastinum.  It  may  be  trephined  to  open  mediastinal  abscess  or  for 
pericardial  paracentesis. 

The  sternum  may  be  fractured  by  direct  violence,  as  by  the  violent 
contact  with  the  chin,  or  by  indirect  violence,  as  by  the  traction  of  the 
muscles  when  the  body  is  forcibly  bent  backward.  It  is  often  associated 
with  fracture  or  dislocation  of  the  spine  due  to  hyperflexion  or  exten- 
sion. The  fracture  is  usually  transverse  and  occurs  most  often  at  or  near 
the  juncture  of  the  manubrium  and  body,  the  narrowest  part  of  the  bone. 
The  body  of  the  sternum  with  the  ribs  is  commonly  displaced  forward. 
The  lesion  is  often  a  dislocation  in  whole  or  in  part  through  the  joint 
between  the  manubrium  and  body.  In  old  age  when  this  joint  is  ossified 
the  tendency  to  fracture  is  increased  by  making  the  chest  more  rigid. 
Fracture  of  the  sternum  is  not  common  owing  to  the  elasticity  of  the  ribs 
and  costal  cartilages  which  support  it,  the  elasticity  of  the  sternum 
which  is  formed  of  two  parts  articulated  together  at  a  slight  angle,  and 
the  soft  cancellous  character  of  the  bone.  The  cancellous  structure  and 
its  exposure  to  slight  injuries  accounts  for  its  being  often  attacked  by 
tuberculous  or  syphilitic  caries  and  for  its  ready  absorption  from  the 
pressure  of  an  aneurysm. 

The  tip  of  the  ensiform  cartilage  may  bend  forward  or  backward. 
The  ensiform  often  presents  median  apertures,  and  it,  as  well  as  its 
articulation  with  the  sternum,  may  become  ossified  in  advanced  age. 
The  costal  cartilages  by  their  elasticity  increase  the  resistance  of  the 
sternum  and  ribs  to  injury.  When  they  become  ossified  in  advanced 
age  the  ribs  and  sternum  are  more  exposed  to  fracture.  They  increase 
in  obliquity  from  the  third  down,  and  in  length  down  to  the  seventh. 
When  the  ribs  are  raised  in  inspiration,  the  costal  cartilages  are  raised 
and  become  more  horizontal.  This  throws  the  ribs  outward,  increasing 
the  transverse  diameter  of  the  thorax.  When  inspiration  is  completed 
their  resiliency  brings  them,  and  with  them  the  ribs,  into  their  normal 
position  so  that  quiet  expiration  requires  no  muscular  action.  At  the 
border  of  the  sternum  only  the  first  two  or  three  interspaces  between  the 
costal  cartilages  are  wide  enough  to  operate  through,  as  in  ligation  of  the 
internal  mammary  artery.  Below  this  the  spaces  are  so  narrow  that 
resection  of  the  cartilages  is  necessary  to  expose  the  parts  beneath. 

The  Ribs. — The  ribs  increase  in  obliquity  from  above  downward. 
They  increase  in  length  as  far  as  the  seventh,  and  thence  they  decrease. 
The  raising  of  the  ribs  in  inspiration  shortens  the  thorax  but  increases 
the  anteroposterior  and  the  transverse  diameters.  The  latter  diameter 
is  also  increased  by  the  throwing  out  of  the  ribs  at  the  side,  in  the  rotation 
that  occurs  on  an  axis  passing  through  their  two  articulations.  This 
rotation  accounts  for  all  the  movements  of  the  ribs. 

The  ribs  are  unequally  exposed  to"  injury.    The  upper  ribs,  first  and 


PLATE  XXIII 


FIG.  86 


.NTERCOSTAL  VEIN 
.NTERCOSTAL  ARTERY 
INTERCOSTAL    NERVE 

INT.    INTERCOS- 
TAL   FASCIA 
INT.    INTERCOS- 
TAL   MUSCLE 
PLEURA 


SUPERFICIAL    FASCIA 
EXT.    INTERCOSTAL 

FASCIA 
EXT.     INTERCOSTAL 

MUSCLE 


PERIOSTEUM 


Vertical  Section  of  the  Sixth  Intercostal    Space   at   the  Junction 
of  its  Posterior  and  Middle  Thirds.     (Tillaux.) 


THE  THORACIC  WALLS  23J 

second,  are  protected  by  the  overlying  pectoral  muscle  and  the  clavicle 
the  lower  or  false  ribs  by  their  small  size  or  their  mobility,  due  to  their 
long  cartilages,  etc.  Hence  it  is  the  ribs  in  the  middle  of  the  series, 
fourth  to  eighth,  that  are  most  often  fractured.  In  advanced  age  the  ribs 
are  more  liable  to  fracture,  owing  to  the  ossification  of  the  cartilages. 

Fracture  may  be  due  to  direct  or  indirect  violence,  most  often  to  the 
former.  It  may  also  be  due  to  muscular  violence  as  in  coughing,  partu- 
rition, etc.;  but  in  such  cases  the  ribs  are  probably  pathologically  weak- 
ened. Indirect  fractures  are  due  to  some  excessive  pressure,  such  as  being 
run  over.  This  tends  to  increase  or  decrease  the  curve  of  the  ribs,  by  press- 
ing their  extremities  together  or  apart,  until  they  break,  theoretically  near 
the  middle  of  their  curve,  but  practically  in  their  anterior  third  near  the 
point  of  application  of  the  violence  or  in  the  posterior  third.  Such  violence 
usually  fractures  more  than  one  rib,  and  is  liable  to  injure  the  viscera  as 
well.  Theoretically,  the  ends  should  project  outward  toward  the  skin, 
but  practically,  we  find  that,  owing  to  the  thick  periosteum  and  the  inter- 
costal muscles  which  bind  the  ribs  firmly  together,  displacement  of  the 
ends  does  not  occur  to  any  great  extent,  especially  if  only  one  rib  is  frac- 
tured. Hence  there  is  rarely  any  deformity  unless  several  consecutive 
ribs  are  fractured.  For  the  same  reason,  and  the  intraperiosteal  character 
of  many  fractures,  crepitus  and  false  motion  are  often  not  to  be  elicited. 
It  is  probably  true,  however,  that  injury  of  the  lung  by  the  fragments, 
though  it  may  occur  in  indirect  fractures,  is  less  common  than  in  direct 
fractures,  in  which  the  lesion  is  beneath  the  blow  and  the  fragments,  if 
displaced  at  all,  tend  to  be  driven  inward,  lacerating  the  pleura  and  lung, 
and  causing  hemo-  or  pneumothorax,  subcutaneous  emphysema,  hemop- 
tysis, pleurisy,  etc.  In  both  forms  of  fracture  the  side  of  the  chest  injured 
is  strapped  to  lessen  the  movements  of  the  ribs  and  thereby  the  pain  on 
thai  side.  The  tendency  to  involuntary  immobilization  of  the  chest  wall 
in  inflammatory  affections  or  after  injury  is  of  some  diagnostic  value. 

Notwithstanding  the  constant  movement  at  the  articulations  of  the 
ribs,  they  are  singularly  i'n-<-  from  disease,  and  dislocation  is  very  rare. 

Resection  of  one  or  more  ribs  is  practised  for  necrosis  or  caries,  often 
tuberculous,  syphilitic,  or  post-t  yphoidal,  for  drainage  of  an  empyema,  or 

in  the  Estlander  or  Schede  operation  for  chronic  empyema.  In  resection 
the  periosteum  is  incised  and  separated  from  the  rib,  i.  <•.,  the  rib  is 

resected  SlAperiosteoUy.     In  this  way  we  avoid  injury  to  the  pleura,  which 

i^  separated  from  the  ribs  by  the  periosteum  and  the  endothoracic  fascia 

lining  the  chest  cavity.    The  intercostal  vessels  (tin/  nerves,  in  the  grooves 

behind  the  lower  border  of  the  rib,  are  also  avoided,  for  they  lie  behind 

the  periosteum  (Fig.  86).    Resection  of  an  inch  or  so  of  rib  is  done  to 

allow  more  tree  drainage  than  is  secured  through  the  narrow  intercostal 

ipaces.    The  seventh  rib,  or  the  rib  above  or  beloia  it,  in  the  midaxillary 

line  j^  ii  ii;illv  selected.  In  the  scapular  line  we  m.i  s  reseet  ;i  rib  or  two 
lower.     As  the  ribs  form  ;i  linn  inch,  there  i,  no  opportunity  lor  retraction 

of  the  thoracic  wall  to  obliterate  the  cavity  of  ;i  chronic  empyema,  and 
the  lungs  me  bound  down  and  cannoi  expand.  The  Estlander  and 
Schede  operations  meet  this  difficulty  by  resecting  several  inches  of  ;i 


232  THE  THORAX 

number  of  consecutive  ribs  over  the  cavity.  The  arch  of  the  ribs  is 
thus  broken,  and  both  ends,  as  well  as  the  intervening  soft  parts,  may 
sink  in  and  help  to  close  the  cavity  beneath. 

The  Intercostal  Spaces. — The  intercostal  spaces  are  narrower  behind 
than  in  front,  in  expiration  than  in  inspiration,  and,  in  lateral  inclination 
of  the  thorax,  on  the  side  toward  which  it  is  inclined  than  on  the  opposite 
side.  The  third  space  is  the  widest,  and  next  in  order  the  second,  first, 
fourth,  etc.  Any  of  the  first  five  spaces  will  admit  the  index  finger.  The 
contents  of  the  intercostal  spaces  include  the  external  and  internal  inter- 
costal muscles,  covered  externally  by  a  thin  fascial  layer  and  internally 
by  the  endothoracic  fascia  and  separated  from  one  another  by  a  layer  of 
cellular  tissue  in  which  lie  the  intercostal  vessels  and  nerves  (Fig.  86). 
Between  the  endothoracic  fascia  and  the  pleura  is  a  loose  subpleural 
cellular  layer.  Pus  from  disease  of  the  thoracic  vertebrae  or  the  posterior 
part  of  the  ribs  may  work  around  in  the  intercostal  spaces  and  appear 
even  as  far  forward  as  the  sternum. 

Vessels  of  the  Thoracic  Wall. — The  Intercostal  Arteries. — The  aortic 
and  superior  intercostals  supply  intercostal  arteries  for  each  space. 
Between  the  vertebrae  and  the  angles  of  the  ribs  the  intercostal  vessels 
pass  more  horizontally  than  the  ribs  till  they  reach  the  cover  of  the  lower 
border  of  the  ribs,  near  the  angles.  In  crossing  this  part  of  the  intercostal 
spaces  they  give  off  smaller  branches  which  pass  to  and  along  the  upper 
margins  of  the  ribs,  and  they  are  exposed  to  injury  by  incisions  or  para- 
centesis. Similarly  in  the  anterior  third  of  the  intercostal  spaces,  where 
they  anastomose  with  branches  from  the  internal  mammary  artery,  they 
abandon  the  protection  of  the  ribs  and  are  more  or  less  exposed.  But 
here,  owing  to  their  small  size,  their  injury  is  not  as  serious  as  posteriorly, 
where  a  fatal  hemorrhage  may  result.  Hence  incision  and  paracentesis 
are  to  be  avoided  posteriorly  and  anteriorly  and  practised  more  at  the 
sides.  As  the  vessels  lie  much  nearer  the  pleura  than  the  surface,  they 
are  likely  to  bleed  into  the  pleural  cavity  when  wounded  unless  the  wound 
is  very  freely  open  superficially.  It  is  remarkable  that  the  intercostal 
vessels,  lying  in  such  close  contact  with  the  ribs,  are  almost  never  injured 
in  fractures  of  the  ribs.  This  is  explained  by  the  protection  afforded  by 
the  periosteum  and  the  fact  that  the  fragments  are  rarely  displaced. 
Owing  to  the  protection  of  the  ribs,  in  the  greater  part  of  their  course  the 
intercostal  arteries  are  seldom  wounded,  but  if  wounded  they  are  diffi- 
cult to  secure  without  injury  to  the  pleura. 

Paracentesis  may  be  done  with  care  in  any  space  within  the  limits  of 
the  pleura  where  fluid  can  be  diagnosticated.  It  is  usually  performed  in 
the  sixth  or  seventh  spaces  midway  between  the  axillary  lines,  where  the 
overlying  muscles  are  thin,  or  near  the  posterior  axillary  line,  or  in  the 
seventh  or  eighth  spaces  just  outside  the.angle  of  the  scapula,  where  the 
latissimus  dorsi  must  be  punctured.  Especial  care  must  be  taken  in 
the  lower  spaces,  like  the  ninth  in  the  posterior  axillary  line,  not  to 
puncture  the  diaphragm,  but  when  there  is  much  fluid  the  diaphragm 
is  much  pressed  down.  The  needle  or  trocar  is  entered  midway  between 
the  ribs,  to  avoid  the  intercostal  vessels,  and  in  inspiration,  for  the  spaces 


THE  THORACIC  WALLS  233 

are  then  wider.  The  spaees  maybe  widened  laterally  by  bending  to  the 
opposite  side.  The  same  rules  apply  to  incisions,  which,  however,  can 
be  made  in  the  lowest  spaces  with  greater  safety  than  puncture,  as  they 
are  not  made  blindly. 

The  Intercostal  Veins. — The  intercostal  veins  accompany  the  arteries, 
lying  above  them.  Those  in  the  upper  six  or  seven  spaces  anastomose 
with  the  branches  of  the  axillary  vein  (Braune).  The  subcutaneous 
veins  of  the  thorax  form  an  anastomosis  between  the  axillary  and  the 
femoral  veins,  usually  through  the  superficial  epigastric  veins  (see  the 
Veins  of  Abdominal  Wall). 

The  Internal  Mammary  Artery. — The  internal  mammary  artery  runs  a 
finger's  breadth  from  the  sternal  margin  behind  the  cartilages  and  inter- 
spaces. It  is  separated  from  the  pleura  in  the  upper  two  spaces  by  the 
endothoracic  fascia,  which  is  here  thicker  than  elsewhere,  and  in  the 
succeeding  four  spaces  by  the  triangularis  sterni  muscle.  As  it  is  a  vessel 
of  some  size,  serious  or  fatal  hemorrhage  may  follow  its  injury,  and  the 
bleeding  is  most  likely  to  occur  internally  into  the  pleural  cavity.  As 
wounds  of  this  artery  are  uncommon,  its  ligation  is  seldom  called  for 
but  may  be  done  in  one  of  the  three  or  four  upper  spaces.  Below  this 
the  spaces  are  so  narrow  as  to  require  resection  of  the  cartilages.  The 
third  space  is  preferable,  as  this  is  wider  in  front  than  the  fourth  and  the 
pleura  is  protected  by  the  intervention  of  the  triangularis  sterni  and  not 
merely  by  the  endothoracic  fascia,  as  in  the  second.  On  either  side  of 
the  artery,  especially  mesially,  wre  may  find  sternal  lymph  nodes. 

The  Intercostal  Nerves. — The  intercostal  nerves  (or  anterior  divisions 
of  the  thoracic  nerves)  lie  below  the  arteries  in  their  course  behind  the 
lower  border  of  the  ribs,  though  they  are  at  first  above  them  in  the  upper 
four  spaces.  They  supply  the  costal  pleura  as  well  as  the  skin  over  the 
greater  part  of  the  abdominothoracic  region,  so  that  pain  over  the  upper 
part  of  the  abdomen  may  be  peripheral  pain  due  to  pleurisy  or  to  pressure 
on  the  nerves  by  pleural  collections  of  fluid,  thoracic  tumors,  curies  of  the 
lower  thoracic  vertebrae,  etc.  The  lateral  cutaneous  branches  perforate 
the  thoracic  wall  at  the  digitations  of  the  serratus  magnus  and  the  external 
abdominal  oblique.  In  intercostal  neuralgia  "tender  points"  are  found 
where  these  lateral  branches,  the  anterior  cutaneous  and  less  often  the 
cutaneous  branches  of  the  posterior  primary  division,  pierce  the  muscles, 
i. e.t midway  between  the  mammary  and  axillary  lines,  near  the  para- 
sternal  line,  and  near  the  median  line  posteriorly,  respectively.  The  lateral 
cutaneous  branch  of  the  second  nerve  crosses  the  axilla  (Fig.  67)  to  end 
in  the  skin  of  the  inner  and  back  pari  of  the  arm  (intercostohumeral 
nerve),  when-  pain  may  be  fell  in  pleurisy  of  the  upper  pari  of  the  pleura, 

in  angina  pectoris,  or  from  pressure  on  the  nerve  in  axillary  suppura- 
tion or  in  enlargement  of  the  axillary  lymph  nodes.    The  intercostal 

nerves  supply  both    the   intercostal  and   the  abdominal   mUScleS   (see  also 

Nerves  of  Abdominal  Muscles).  It  should  be  remembered  that  the  skin 
over  tli<-  upper  part  of  the  thorax  is  also  supplied  by  the  superficial 

tiding  bra  riches  of  the  cervical  plexus.    The  posterior  divisions  of  the 
thoracic  nerves  descend  a  considerable  distance  before  ending  in  the  skin. 


234  THE  THORAX 

This  partly  accounts  for  the  fact  that  the  line  of  anesthesia  in  fracture  of 
the  thoracic  spine  and  the  line  of  pain  and  cutaneous  eruption  in  herpes 
zoster  is  nearly  horizontal  and  not  oblique.  This  also  depends  upon 
the  fact  that  the  lesion  involves  the  spinal  segments  rather  than  the 
peripheral  nerves. 

The  superficial  lymphatics  mostly  enter  the  axillary  nodes;  others,  near 
the  sternum,  may  enter  the  sternal  nodes  along  the  internal  mammary 
artery  or  cross  the  median  line  to  the  opposite  axilla ;  while  others  above 
may  cross  the  clavicle  and  enter  the  subclavian  nodes.  The  deeper 
lymphatics  in  the  intercostal  spaces  run  in  two  sets,  the  deeper  ones,  just 
beneath  the  pleura  and  receiving  its  lymph  channels,  pass  forward 
to  the  sternal  nodes  along  the  internal  mammary  artery;  the  more  super- 
ficial ones  pass  backward,  through  small  nodes  at  the  back  of  the  inter- 
costal spaces,  and  enter  the  thoracic  duct.  These  deeper  vessels  anas- 
tomose with  those  entering  the  axillary  nodes. 


THE  BREAST. 

The  breast  {mamma)  at  birth  and  up  to  puberty  is  equally  undeveloped 
in  both  sexes.  A  slight  secretion  of  a  collostrum-like  fluid,  with  evi- 
dences of  inflammation,  may  sometimes  occur  in  the  newborn  and  in 
boys  at  the  time  of  puberty.  Very  rarely  the  breast  is  well-developed 
and  functionally  active  in  men. 

The  female  breast,  though  it  develops  much  at  puberty,  does  not  reach 
its  full  functional  development  until  the  end  of  pregnancy  and  during 
lactation.  After  lactation  the  breast  returns  to  its  former  condition  until 
again  stimulated  by  a  subsequent  pregnancy.  After  the  menopause  the 
breast  atrophies,  and  at  this  time  is  quite  likely  to  be  attacked  by  cancer. 

The  virgin  breast  is  hemispherical,  extending  between  the  third  and 
sixth  ribs  and  between  the  sternal  and  anterior  axillary  borders.  Its 
circumference  is  not  quite  circular,  but  presents  three  cusps,  one  toward 
the  sternum  and  two  toward  the  axillary  line,  one  above  and  one  below. 
After  repeated  pregnancies  the  breast  becomes  more  flabby  and  pendent, 
so  that  its  position  is  not  a  reliable  landmark.  In  certain  black  races,  as 
in  the  Basutos,  it  is  flask-shaped  and  may  even  be  flung  over  the  shoulder 
or  beneath  the  axilla,  so  that  the  infant  may  suckle  on  the  back. 

The  breast  (Fig.  87)  lies  upon  the  pectoralis  major  muscle,  about  one- 
third  of  the  gland  overlapping  it  onto  the  serratus  magnus,  and,  if  large, 
onto  the  origins  of  the  external  oblique  and  rectus.  The  superficial  fascia 
of  the  region  splits  to  enclose  and  support  it,  and  sends  fibrous  processes 
to  connect  the  several  lobes  together.  Fibrous  trabecular  connect  the  gland 
with  the  overlying  skin  and  more  loosely  with  the  underlying  pectoral 
fascia.  The  enclosing  fascia  is  rich  in  fat,  which  thus  comes  to  lie  in  front 
and  behind  the  gland  and  between  its  lobes.  Except  during  lactation,  and 
oftentimes  then,  the  size  of  the  mamma  is  largely  due  to  the  relative  amount 
of  this  fat,  which  gives  the  breast,  with  its  15  to  20  lobes,  its  smooth  and 
uniform  contour  and  elastic  consistency.      Hence  the  large  size  of  the 


THE  BREAST 


235 


breast  is  no  indication  of  good  nursing  qualities  but  often  the  reverse, 
the  fat  being  developed  at  the  expense  of  the  gland  tissue.  During  lacta- 
tion and  in  conditions  of  emaciation  the  fat  is  largely  absorbed,  so  that 
the  gftind  feels  more  distinctly  lobular.  Posteriorly  the  mamma  is  loosely 
connected  with  the  pectoral  fascia  by  loose  connective  tissue  which  may 
enclose  large  lymph  spaces,  the  so-called  submammary  bursa.  This 
is  one  of  the  sites  selected  for  injection  of  hot  normal  saline  solution  in 
shock  or  sepsis. 

Fig.  87 


FIRST 
RIB 


TORALIS 

NOR 

1COSTAI.ES 
ATH    OF    PEC- 

LIS     MAJOR 

B 


ISSUE 
kl_    PLANE 
PLE 


Right  bread  in  aogittal  lection,  innei  surface  of  outer  segment.     (Gerriah,  after  Testul  I 

Normally  the  breast  should  be  movable  in  nil  directions  on  the  pec- 
toral muscle;  the  failure  of  such  mobility  indicates  deep  extension  of  the 
growth  in  cancer  of  the  breast.  This  mobility  should  be  tested  after  the 
muscle  is  made  firm  by  its  contraction,  and  especially  in  the  line  of  its 
fibers.  At  the  lame  time  the  breast  moves  somewhat  with  the  movement 
of  the  muscle,  hence  the  arm  should  be  held  at  nest  in  inflammation  of 
the  gland. 

It  i  mo  i  important  to  remember  thai  imall  glandular  extensions 
may  pass  from  the  base  of  the  gland  to  and  even  through  the  pectoral 


236  THE  THORAX 

fascia  so  as  to  lie  upon  or  in  the  muscle.  It  follows  that  every  operation 
of  excision  of  the  breast  for  cancer,  to  be  thorough,  should  remove  this 
fascia  and  the  surface,  if  not  the  entire  thickness,  of  the  underlying 
pectoral  muscle.  Similarly  the  fibrous  trabecules  (suspensory  ligaments 
of  Cooper),  which  connect  the  gland  with  the  skin,  may  contain  true 
glandular  tissue  (Stiles),  and  explain  the  frequent  extension  to  the  skin; 
hence  no  overlying  skin  should  be  left  in  excision  for  cancer.  The  con- 
traction of  a  carcinoma  pulling  on  these  trabecular  may  produce  a  number 
of  small  depressions  or  dimples,  like  those  on  an  orange,  which  is  a  very 
valuable  diagnostic  sign  of  cancer. 

The  overlying  skin,  except  that  of  the  areola,  should  be  freely  movable, 
but  in  abscess  or  advanced  carcinoma  it  may  become  adherent,  and 
in  some  cases  of  the  latter  it  is  infiltrated  with  small  nodules  of  carci- 
noma. In  lactation  or  in  cases  of  carcinoma  or  sarcoma  the  large  and 
numerous  subcutaneous  veins  are  often  very  plainly  visible.  The  skin  of 
the  areola  and  nipple  is  fatless,  pigmented,  very  thin  and  sensitive,  and 
adherent  to  the  parts  beneath.  Besides  highly  developed  papillae,  the  skin 
of  the  nipple  contains  numerous  sebaceous  glands,  whose  secretion  protects 
the  nipple  from  the  saliva  of  the  infant  and  guards  it  from  fissures.  The 
latter  occur  most  often  in  the  groove  between  the  nipple  and  the  areola, 
where  none  of  these  glands  open. 

Beneath  the  skin  of  the  nipple  and  areola  are  pale  muscle  fibers,  both 
circular  and  radiating,  which  act  as  a  sphincter  on  the  lacteal  ducts 
traversing  the  nipple.  By  their  contraction  a  part  of  the  areola  is  drawn 
up  into  the  nipple,  thus  lengthening  and  erecting  the  latter,  which  is  not 
really  an  erectile  body.  The  lacteal  ducts,  one  for  each  lobe  of  the  gland, 
after  enlarging  into  a  spindle-shaped  ampulla  or  reservoir  beneath  the 
areola,  converge  to  and  traverse  the  nipple  to  open  separately  by  fine 
orifices  (J  mm.  in  diameter)  near  its  tip. 

Besides  ordinary  eczema  of  the  areola  and  nipple,  these  may  be  the 
seat  of  a  chronic,  superficial,  finely  granular,  raw  condition  known  as 
Paget' s  disease  of  the  nipple,  which  usually  results  in  epithelioma  of  the 
lacteal  ducts.  By  a  contraction  of  the  lacteal  ducts,  or  of  new  connective 
tissue  about  them,  in  scirrhus  cancer,  centrally  situated,  the  nipple  may 
be  retracted  so  as  to  present  a  depression  instead  of  a  projection. 

The  Nipple. — The  nipple  averages  12  mm.  Q-  in.)  in  length,  lies  a  little 
below  and  internal  to  the  centre  of  the  gland,  and  points  outward.  In  the 
virgin  it  corresponds  to  the  fourth  interspace  (or  fifth  rib)  10  cm.  (4  in.)  from 
the  median  line,  but  its  position  is  very  variable  after  pregnancy  or  in  old 
age.  In  some  cases  it  is  depressed  below  the  surface  so  as  to  prevent 
nursing.  The  consistency  of  the  breast  is  firm  without  being  hard.  It  is 
not  entirely  uniform  in  all  parts,  but  if  any  part  is  distinctly  hard  it  is 
pathological.  To  detect  neoplasms,  cysts,  etc.,  the  breast  should  be 
palpated  against  the  chest  wall  and  compared  with  the  opposite  breast. 
The  normal  breast,  if  palpated  between  the  fingers  and  thumb,  may  be 
mistaken  for  a  tumor. 

Abscess  of  the  Breast. — Abscess  of  the^breast  is  not  uncommon  during 
lactation,  and  is  usually  due  to  an  infection  carried  by  the  lymphatics 


THE  BREAST  237 

from  a  fissure  or  eczema  of  the  nipple  or  areola.  It  may  occur  in  three 
situations:  (1)  in  the  fatty  connective  tissue  superficial  to  the  breast; 
(2)  in  the  breast  tissue  itself  or  its  interlobular  tissue;  and  (3)  in  the 
loose  submammary  connective  tissue.  It  occurs  most  often  in  the  breast 
tissue,  and  one  or  more  lobes  or  the  entire  organ  may  be  involved.  Inci- 
sions to  open  mammary  abscess  should  radiate  from  the  nipple  to  avoid 
damage  to  the  lacteal  ducts. 

The  Blood  Supply. — -The  blood  supply  of  the  mamma  comes  mainly 
from  the  long  thoracic  artery  (external  mammary) ,  which  follows  the  outer 
border  of  the  pectoralis  minor,  and  from  the  second,  third,  fourth,  and 
fifth  perforating  intercostal  branches  of  the  internal  mammary  artery, 
and,  in  addition,  from  the  corresponding  aortic  intercostals  and  perhaps 
from  the  acromiothoracic.  The  veins  follow  the  same  course.  These 
arteries  and  veins  are  divided  in  excision  of  the  breast. 

The  Lymphatics. — The  lymphatics  are  of  special  importance,  as  it 
is  through  them  that  metastatic  infection  occurs  in  carcinoma  of  the 
breast.  The  superficial  or  subcutaneous  lymphatics  at  the  periphery 
of  the  breast  do  not  differ  from  those  of  adjacent  regions,  but  beneath 
the  areola  they  form  a  very  close  network  from  which  many  small  trunks 
pass  to  the  subareolar  plexus,  in  which  the  majority  of  the  deep  or  glandu- 
lar set  of  lymphatics  also  terminate.  Its  principal  outlet  is  by  two  or  three 
large  vessels  which  pass  directly  outward  and  then  along  and  beneath 
the  external  border  of  the  pectoralis  major,  perforate  the  axillary  aponeu- 
rosis, and  terminate  in  the  pectoral  group  of  the  axillary  nodes.  (See  Lym- 
phatics of  Axilla,  p.  188.)  The  first  two  nodes  which  these  vessels  enter, 
and,  consequently,  the  first  to  be  affected  by  metastatic  growth  in  cancer 
of  the  breast,  usually  lie  on  the  third  rib  on  the  serration  of  the  serratus 
magnus.  From  these  the  infection  spreads  to  other  axillary  nodes  and 
finally  to  the  subclavicular  nodes.  Hence  we  see  the  necessity  of  complete 
removal  of  the  axillary  nodes  and  contents  in  any  operation  for  carcinoma. 
In  addition  there  are  certain  accessory  lymph  channels,  of  importance  in 
metastasis.  From  the  inner  part  of  the  gland  Lymph  vessels  perforate  the 
pectoral  muscle  and  pass  through  the  intercostal  spaces  to  the  sternal 
nodes, along  the  internal  mammary  artery,  and  thus  reach  the  mediastinal 

nodes,  whence  indirectly  the  liver, pleura, and  lungs  may  become  involved. 

Involvement  of  the  eternal  nodes  is  rare,  probably  due  to  the  atrophy  of 

this  channel  in  senile  mamma?,  in  which  cancer  usually  occurs.     In  10 

per  cent,  of  cases  a  lymph   trunk  from   the  posterior  surface  perforates 

the  pectoralis  major  and,  ascending  between  it  and  the  pectoralis  minor, 
reaches  the  subclavicular  nodes.  As  the  superficial  lymphatics  of  the  inner 

pari  of  the  breast  may  crOSS  the  median  line  and  enter  the  nodes  in  the 
opposite  axilla,  the  in  vol  Yemeni  of  the  latter  sometimes  occurs. 

\      the    mamma    is   supplied   by    the   ClUaneOUS  branches  of  the  second, 

third,  fourth,  and  fifth  intercostal  nerves,  abscess  or  other  painful  affections 

of  the  breast   may  cause  pain   referred   to  the  side  or  back  of  the  thorax 

intercostal  trunks),  the  region  over  the  scapula  (posterior  divisions  of 

the   thoracic  nerves),  or  down  the  arm  (intercostolniincra  I  branch  of  the 

ond  intercostal).     Tain  shooting  up  the  nek  is  probably  along  the 


238 


THE  THORAX 


supraclavicular  branch  of  the  cervical  plexus,  which  reaches  the  upper 
part  of  the  gland  and  also  communicates  with  the  second  intercostal. 

Of  the  neoplasms  of  the  female  breast  85  per  cent,  are  carcinomatous. 
They  originate  most  frequently  in  the  upper  and  outer  quadrant.  From 
what  has  been  said  above,  as  to  the  lymphatics  and  the  extensions  from 
cancer  of  the  breast,  it  follows  that  in  operations  for  carcinoma  it  is 
necessary  to  remove  a  liberal  area  of  overlying  skin,  the  entire  contents 
of  the  axilla,  so  as  to  include  all  the  lymphatics,  and  not  only  the 
surface  of  the  pectoralis  major  but  the  entire  muscle  beneath  the  breast. 
Benign  tumors  include  fibromata  and  adenomata.  Sarcoma  of  the  breast 
develops  from  the  connective-tissue  stroma  of  the  gland,  carcinoma 
from  the  epithelial  elements  of  the  ducts  and  glands. 


Fig. 


DELTO-PECTORAL      HUMERAL  CHIilN 


THORACIC 
CHAIN 


CUTANEOUS  COLLECTING 

TRUNK    FROM   THE 

THORACIC   WALL 


MAMMARY   LYMPHATIC 
ENDING  IN  SUB- 
CLAVIAN GLANDS 


THORACIC 
CHAIN 

MAMMARY   COL- 
LECTING TRUNKS 


SUBAREOLAR 
PLEXUS 


CUTANEO 
'-ECTING 


LLECTING  TRUNKS! 
PASSING  TO  INTERNAL 
MAMMARY   GLANDS 


Axillary  glands  and  lymphatics  of  the  breast. 


Abnormalities. — Small  supplementary  glands  are  not  infrequently 
present  around  or  near  the  mamma,  and  may  be  the  starting  point  of 
tumors.  Occasionally  additional  mammw  or  nipples  exist,  sometimes 
in  the  axilla,  but  more  often  (90  per  cent.)  below  the  regular  glands, 
converging  toward  the  median  line  so  as  to  follow  the  course  of  the 
internal  mammary  and  deep  epigastric  vessels.  They  may  even  occur 
in  the  groin.  As  many  as  three  pair  in  one  case  and  in  another  five 
milk-secreting  glands  have  been  observed.  The  occurrence  of  these  is 
explained  by  reversion  or  atavism.  Absence  and  imperfect  development 
of  the  breasts  are  rare  and  usually  associated  with  absence  or  arrested 


THE  DIAPHRAGM  239 

development  of  the  sexual  organs.  The  nipples  on  either  or  both  breasts 
may  be  double  or  even  triple,  or  again  they  may  be  wanting.  Asymmetry 
of  the  breast  is  common,  the  left  is  usually  the  larger  and  is  more  often 
the  seat  of  newgrowths  and  of  hypertrophy. 


THE  DIAPHRAGM. 

The  diaphragm,  situated  at  the  junction  of  the  superior  third  with  the 
inferior  two-thirds  of  the  trunk,  forms  the  floor  of  the  thoracic  cavil ij 
and  the  roof  of  the  abdomen.  It  is  a  double  or  bilateral  muscle,  with  a 
central  tendon.  Its  muscular  fibers,  arranged  peripherally,  may  be 
divided  into  sternal,  costal,  and  lumbar  (or  vertebral)  portions.  Between 
these  portions  the  muscle  fibers  may  be  wanting  over  a  greater  or  less 
>]>ace,  so  that  the  serous  or  subserous  layers  on  either  side  come  together. 
Thus  the  muscle  fibers  are  often  wanting  between  the  vertebral  part, 
comprising  the  crura  and  the  fibers  from  the  arcuate  ligaments,  and  the 
costal  part  (hiatus  diaphragmaticus),  favoring  the  passage  of  inflamma- 
tion or  pus  from  a  perinephritic  abscess  into  the  pleural  cavity,  or  the 
occurrence  of  a  hernia.  Similarly  between  the  sternal  portion,  from  the 
back  of  the  xiphoid  cartilage,  and  the  costal  portion  on  either  side  are 
gaps  devoid  of  muscle,  covered  above  by  pleura  on  the  right  side  and 
pericardium  on  the  left.  Through  these  gaps  pass  the  superior  epigas- 
tric arteries  and  some  hepatic  lymphatics,  on  their  way  to  the  mediastinal 
glands.  Also  between  the  two  halves  of  the  sternal  (xiphoid)  insertion 
is  usually  a  gap  through  which  the  cellular  tissue  of  the  mediastinum  is 
continuous  with  the  subperitoneal  connective  tissue,  and  through  this 
gap  inflammation  and  pus  may  pass  from  the  mediastinum  to  the  epi- 
gastric region  or  vice  versa. 

Through  some  one  of  the  above  gaps  diaphragmatic  hernia,  usually 
congenital,  sometimes  acquired,  is  most  likely  to  occur.  In  the  former 
variety  one  of  the  gaps,  especially  the  xiphocostal,  may  be  congenita  lb- 
large  or  a  portion  of  the  diaphragm  may  be  deficient.  The  acquired  form 
is  due  to  a  muscular  strain  or  external  violence.  It  may  be  suddenly 
acquired,  as  by  a  full  or  blow,  in  which  case  there  is  likely  to  be  rupture 
of  the  peritoneum  and  hence  no  sue;  or  gradually  acquired,  as  by  strain- 
ing, coughing,  etc.,  when  a  sac  is  usually  present.  Almost  any  of 
tin'  abdominal  viscera,  but  especially  the  stomach,  colon,  and  omentum, 

form    the   contents  of  such    ;i    henii;i    in    the    pleural    cavity.      The   lungs, 
owing  to  their  elasticity,  are  never  herniated  into  the  abdomen.      .Many 

of  iIk-  acute  acquired  cases  are  rapidly  fatal  and  often  are  not  diagnos- 
ticated antemortem,  but    if  diagnosticated  surgical  intervention  offers 

tin-  only  hope. 

The  fleshy  portion  of  the  diaphragm,  arising  in  an  oblique  line  from 

the  baw  of  the  xiphoid  cartilage  to  the  lasl   rib,  passes  at  lirst   vertically 

upward,  connected  with  the  inner  surface  of  the  thorax  by  connective 

lie,  to     the    lower    limit     of     flic     pleura    (see    p.   I'll').       Thence    lined 

above  by  pleura  (diaphragmatic)  it  is  separated  from  die  thoracic  wall  l>\ 


240  THE  THORAX 

a  cleft-like  space  lined  by  pleura  (costophrenic  sinus),  into  which  the  lung 
does  not  descend  in  deep  inspiration.  From  the  level  of  the  lower 
border  of  the  lung  the  diaphragm  curves  upward  and  inward,  concave 
inferiorly,  into  the  trefoil  central  tendon.  Hence  in  the  lower  part 
of  the  bony  thorax  a  wound  involves  the  thoracic  wall,  diaphragm, 
and  peritoneal  cavity;  at  a  higher  level  it  involves  the  thoracic  wall, 
pleural  cavity,  diaphragm,  and  peritoneal  cavity;  still  higher  the  lung 
intervenes  in  the  pleural  cavity.  Unless  the  lower  part  of  the  pleural 
cavity  is  filled  with  fluid  or  gas  the  diaphragm  is  in  close  contact  with  the 
chest  wall  below  the  lower  border  of  the  lung,  a  fact  to  be  remembered 
in  incision  and  aspiration  here. 

The  level  of  the  diaphragm  varies  between  expiration  and  inspiration. 
The  middle  portion  or  central  tendon,  on  the  central  and  left  leaflet  of 
which  rests  the  heart,  stretches  from  the  base  of  the  ensiform  process 
nearly  horizontally  backward  to  the  vertebrae.  This  portion  moves 
slightly  in  respiration  (about  2.5  cm.  [1  in.],  Sibson),  though  Hyrtl 
thought  it  stationary.  The  pericardium  and  heart  must  necessarily 
follow  its  movements,  hence  its  motion  is  slight.  The  dome,  or  highest 
point  of  the  diaphragm,  reaches  the  level  of  the  fifth  chondrosternal  joint 
on  the  right  side,  or  less  than  2.5  cm.  (1  in.)  below  the  nipple,  on  the  left 
the  breadth  of  a  cartilage  lower,  the  presence  of  the  liver  making  the 
right  side  higher.  In  early  life  the  diaphragm  is  higher  than  given 
above,  and  it  is  lower  in  old  age.  The  height  of  the  diaphragm  is  altered 
by  pathological  condition  in  the  thoracic  and  abdominal  cavities.  Thus 
it  is  lowered  in  pleural  or  pericardial  effusions  and  in  emphysema,  and 
raised  when  extensive  adhesions  exist  in  the  pleural  cavities  with 
retraction  of  the  lung,  or  when  tumors,  fluid,  or  tympanites  are  present 
in  the  abdomen.    Its  level  may  be  determined  by  the  x-rays. 

As  to  the  three  openings  in  the  diaphragm,  the  aortic  opening  in  front 
of  the  twelfth  thoracic  vertebra  lies  in  or  slightly  to  the  left  of  the  median 
line.  The  inner  portion  of  the  two  crura,  which  arch  in  front  of  the  aorta 
to  form  the  aortic  orifice,  is  fibrous,  so  that  the  contraction  of  the  dia- 
phragm does  not  cause  compression  of  the  aorta.  The  esophageal  open- 
ing, above  and  in  front  of  the  aortic  opening  and  to  the  left  of  the  latter 
and  the  median  line,  is  oval  and  surrounded  sphincter-like  by  fleshy 
crural  fibers.  It  lies  in  front  of  the  ninth  thoracic  vertebra.  Very  rarely 
the  esophageal  opening  is  found  in  the  right  crus,  in  the  median  line, 
or  to  the  right  of  it.  I  have  found  this  condition  in  one  case  of  gastrotomy, 
preliminary  to  a  retrograde  dilatation  of  an  esophageal  stricture,  and 
another  similar  case  has  been  reported. 

The  pleura  of  both  pleural  cavities  and  the  pericardium  are  closely 
connected  with  the  diaphragm,  the  peritoneum  more  loosely.  The  under 
surface  of  the  heart  resting  on  the  central  tendon  of  the  diaphragm 
explains  the  presence  of  the  heart  beat  in  the  epigastrium,  and  its  exag- 
geration in  hypertrophy  of  the  right  ventricle.  The  liver,  stomach, 
spleen,  pancreas,  kidneys,  and  suprarenals  are  in  contact  with  the  under 
surface  of  the  diaphragm,  the  lungs  and  heart  with  the  upper  surface. 
Subphrenic  abscesses  occur  in  the  subphrenic  space  between  the  under 


THE  PLEURA  241 

surface  of  the  diaphragm  and  the  viscera  in  contact  with  it,  especially 
the  liver.  This  space  is  divided  into  a  right  and  a  left  half  by  the  sus- 
pensory ligament  of  the  liver.  These  abscesses  are  often  secondary  to 
gastric  ulcer. 

The  diaphragm  is  supplied  by  the  phrenic  nerves,  in  paralysis  of  which 
respiration  is  carried  on  almost  entirely  by  the  intercostals,  and  the  epi- 
gastrium sinks  instead  of  protrudes  on  inspiration,  as  the  diaphragm 
no  longer  pushes  the  abdominal  viscera  downward  and  forward.  In 
action  the  diaphragm  increases  the  vertical  diameter  of  the  thorax,  but 
as  it  also  raises  the  lower  six  ribs  it  increases  the  other  two  diameters  in 
the  lower  part.  When  fixed  in  the  position  of  inspiration  by  the  closure 
of  the  glottis,  it  assists  the  abdominal  muscles  in  expulsive  efforts,  defeca- 
tion, parturition,  etc.,  by  pressing  down  the  abdominal  viscera  and  holding 
them  there.  The  abdominal  viscera  press  the  diaphragm  upward  in  the 
supine  position,  hence  many  patients  with  dyspnea  breathe  better  in 
the  sitting  posture. 

THE  PLEURA. 

The  pleura  of  each  side  is  a  large  serous  sac  or  lymph  space  whose 
median  or  mediastinal  wall  is  invaginated  at  one  point  (the  root  of  the 
lungs)  by  the  lung,  whose  outer  surface  it  covers  as  the  visceral  or  pul- 
monary pleura.  Normally  there  is  no  pleural  cavity,  the  opposing 
smooth,  inner  surfaces  of  the  pleura  being  in  contact  with  only  a  slight 
amount  of  fluid  between  to  diminish  friction.  Pathologically  the  pres- 
ence of  fluid  (serum,  pus)  or  air  may  make  a  cavity.  It  is  important 
to  know  the  limits  of  the  pleura  both  for  diagnosis  and  treatment. 

The  dome  of  the  pleura  is  completely  occupied  by  the  apex  of  the  lung 
and,  like  the  latter,  is  grooved  by  the  subclavian  artery  antero-internally, 
hence  in  ligation  of  the  artery  the  pleura  is  in  danger  of  injury.  The 
pleural  dome  and  the  apex  of  the  lung  extend  info  the  root  of  the  neck 
about  .'»rm.  ilj  in.  i,  or  1  to  .">  cm.  above  the  anterior  part  of  the  first 
rib,  but  never  above  its  neck,  and  1  to  3  cm.  above  the  clavicle  in  the 
upright  position,  but  scarcely  or  not  at  all  above  it  in  the  supine 
position  or  in  forced  inspiration,  in  which  positions  the  clavicle  is  ele- 
vated. Clinically  the  resonance  on  percussion  of  the  apex  extends  higher 
above  the  clavicle  than  its  actual  level.  The  dome  of  the  pleura  is  in 
relation  with,  the  SCaleni  medius  and  anticUS  and  the  deep  layer  of  the 
deep  cervical  fascia.  //  lirs  behind  the  inner  end  of  the  clavicle  and  the 
-term, mastoid  muscle,  and  projects  slightly  into  the  base  of  the  posterior 
cervical  triangle. 

The  anterior  borders,  along  which  the  costal  and  diaphragmatic  sur- 
of  the  pleura   meet   in  front,  extend  from  the  dome  downward  and 

inward  behind  the  sternoclavicular  joints  and  the  sternum,  meeting  oppo- 
site the  junction  of  the  ma  nubriiiin  and  the  body  of  that  bone  a  little 
to  the  left  of  the  middle  line.  Prom  this  point  they  descend  vertically, 
nearly,  or  lOmetimes  quite,  in  contact,  to  the  level  of  the  fourth  or 
lit'tli   cartilage,   whence  they  diverge  to  reach   the  seventh  chondroslerna  I 


242 


THE  THORAX 


junction,  leaving  between  them  a  triangular  area  of  sternum  in  contact 
with  the  pericardium.  The  left  pleura,  below  the  fourth  cartilage,  passes 
along  the  left  border  of  the  sternum,  or  at  most  the  inner  ends  of  the 
fourth  to  the  sixth  costal  cartilages,  but  does  not  bend  outward,  as  does 
the  cardiac  incisure  of  the  lung,  to  leave  the  pericardium  bare.  Hence 
under  normal  conditions  the  pericardium  cannot,  as  a  rule,  be  punctured 
through  an  interspace  without  traversing  the  pleura. 


RIGHT    INTER-  At 

LOB     INCISURE         l^fe 


MEDIAN    LOBE 


LOWER    LOBE 


COSTO    PHRENIC_f 
SINUS 


COSTO-MEDI- 
ASTINAL  SINUS 


LEFT    tNTERLOB. 

INCISURE 
CARDIAC 
INCISURE 
COSTO-PERI- 
.  CARDIAL 
SINUS   • 


—  LINGULA 


LOWER   LOBE 


MAMMARY 
LINE 


TRIANGULAR     AREA    OF 
PERICARDIUM     NOT 
COVERED   BY    PLEURA 


MAMMARY 
LINE 


Position  of  the  lungs  and  pleurae  with  reference  to  the  anterior  chest  wall.      (Joessel.) 


The  lower  border  of  the  pleura,  along  which  the  costal  and  diaphrag- 
matic surfaces  meet,  reaches  the  upper  border  of  the  seventh  cartilage  at 
the  side  of  the  sternum,  the  lower  border  of  the  seventh  rib  in  the  mam- 
mary line,  the  ninth  rib  in  the  axillary  line,  and  the  twelfth  rib  or  eleventh 
thoracic  spine  at  the  side  of  the  vertebras.  It  may  extend  slightly  below 
the  inner  end  of  the  twelfth  rib,  occasionally  even  to  the  lower  border 
of  the  first  lumbar  transverse  process  (Pansch),  an  important  point  in 
lumbar  incisions  to  reach  the  kidney  (see  p.  315).  Although  the  left 
pleura  may  extend  somewhat  lower  than  the  right,  owing  to  the  liver  on 
the  right  side,  the  difference  in  level  is  so  slight  that  clinically  it  is  not 


THE  PLEURA 


243 


worth  considering.  The  posterior  border,  extending  between  the  neck  of 
the  first  and  the  head  of  the  twelfth  rib,  is  indicated  in  part  by  a  ridge 
bounding  posteriorly  the  groove  which  on  the  left  .side  is  formed  by  the 
aorta  and  on  the  right  side  by  the  azygos  major  vein. 

Along  the  anterior  and  inferior  borders  the  lungs  do  not  reach  as 
far  as  the  pleura?,  but  leave  an  interval  or  sinus  where  two  layers  of 
parietal  pleura  are  in  contact.  The  costomediastinal  sinus,  or  that  along 
the  anterior  border,  is  filled  by  lung  in  inspiration  on  the  right  side,  but 
on  the  left  side,  opposite  the  cardiac  incisure  of  the  lung,  a  wide  interval 
remains  in  the  fullest  inspiration,  corresponding  to  the  area  of  cardiac 
flatness,  where  the  heart  is  uncovered  by  lung  (costopericardial  sinus) 
(Fig.  89). 

Fig.  90 


LEFT   INTERLOB 
INCISURE 


RIGHT    INTERLOB. 
INCISURE 


LOWER    LOBE 


COSTO-PHRENIC 
SINUS  OF   PLEURA 


LEFT    SCAPULA 
LINE 


RIGHT  SCAPULA 
LINE 


".m  of  the  lunga  .-mil  pleura  with  reference  to  the  poaterior  cheal  twill       I  Foi 


The  costophrenic  sinus,  along  die  lower  border  of  the  pleura,  is  never 
filled  on  die  deepesl  inspiration.  The  extent  of  the  contaci  of  the  costal 
and  phrenic  portions  of  the  pleura  varies  in  different  parts  and  on  inspira- 
tion and  expiration,  and  corresponds  to  the  difference  of  level  of  the 
lower  borders  of  the  pleura  and  lung.  In  quiet  breathing  (his  sinus 
_'  cm.  ;ii  ihc  sternal  and  mamman  lines,  2.5  cm.  near  die 
vertebrae,  and  6  fin.  in  the  axillary  line  (Luschka).  Pathological  fluids 
In  i  colled  here  and  can  here  be  firs!  diagnosticated.    The  presence  of 


244  THE  THORAX 

the  sinus  explains  the  fact  that  a  wound  may  penetrate  the  pleura  and  the 
diaphragm,  and  then  enter  the  peritoneal  cavity  or  the  liver,  without 
involving  the  lung.  Unless  we  are  sure  that  this  sinus  is  full  of  fluid  it  is 
not  safe  to  puncture  the  pleural  cavity  below  the  lower  limit  of  the  lung, 
though  an  incision  may  be  carefully  made  at  the  lower  limit  of  the  pleura. 
The  lower  limit  of  the  sinus  is  still  quite  a  distance  above  the  lower  attach- 
ment of  the  diaphragm  and  the  costal  margin  (about  5  to  6  cm.  [2  to  2\  in.] 
from  the  latter).  The  thin  diaphragm  alone  separates  the  lower  end 
of  the  pleurae  from  the  kidneys.  The  pleura  is  said  to  descend  lower  in 
the  child.  In  children  also  the  thymus  separates  the  anterior  borders  of 
the  pleurse  more  widely  than  they  are  separated  in  the  adult.  The  thick 
costal  pleura  is  so  connected  with  the  endothoracic  fascia-  by  loose  con- 
nective tissue  that  it  is  easily  stripped  up,  while  the  diaphragmatic 
pleura  is  closely  adherent. 

Along  the  root  of  the  lung  the  parietal  (mediastinal)  is  continuous 
with  the  visceral  pleura.  Opposite  and  below  the  root  of  the  lung  the 
mediastinal  pleura  covers  and  is  closely  attached  to  the  outer  surface 
of  the  pericardium,  with  the  phrenic  nerve  between,  hence  the  latter 
may  be  affected  by  inflammation  of  either  membrane. 

The  thin  visceral  or  pulmonary  layer  of  the  pleura,  besides  covering 
and  being  closely  adherent  to  the  surface  of  the  lungs,  dips  down  into  the 
bottom  of  the  fissures,  both  surfaces  of  which  it  lines. 

In  pleurisy,  or  inflammation  of  the  pleura,  the  opposing  surfaces,  pul- 
monary and  parietal,  are  congested  and  then  thickened  and  roughened 
by  cell  proliferation.  The  rubbing  together  of  these  roughened  areas 
during  inspiration  causes  the  friction  sounds  and  pain,  hence  the  chest 
is  strapped  in  pleurisy  to  prevent  the  movement  of  the  lungs.  If  the 
opposed  areas  lose  their  roughness,  become  adherent,  or  are  separated  by 
fluid,  the  friction  sound  disappears.  As  the  intercostal  nerves  supply  the 
intercostal  and  other  respiratory  muscles  as  well  as  the  costal  pleura,  the 
patient  with  pleurisy  neither  will  nor  can  draw  a  deep  breath  on  account 
of  pain,  hence  breathing  is  shallow  and  the  respiratory  sounds  weak. 
The  pain  may  be  referred  to  the  abdomen,  arm,  etc.,  in  the  cutaneous 
distribution  of  the  affected  nerves.  Adhesions  may  form  between 
opposed  roughened  areas  of  the  pleura.  When  fluid  is  extra vasated  this 
first  accumulates  in  the  costophrenic  sinus,  or  posteriorly  in  the  supine 
position.  If  the  fluid  is  excessive  the  lungs  are  pressed  backward  and 
inward  toward  the  hilum  and  the  costovertebral  groove,  the  intercostal 
spaces  bulge,  the  surface  veins  are  distended,  and  the  heart  is  pushed 
toward  the  opposite  side.  In  cases  of  "pleurisy  with  effusion"  running 
a  long  course,  the  hyperplastic  thickening  may  be  very  marked  and  the 
adhesions,  when  the  fluid  is  removed,  may  be  very  extensive. 

In  wounds  penetrating  the  pleura  air  may  enter  the  pleural  cavity, 
causing  pneumothorax.  If  the  opening  is  free,  the  pressure  without  and 
within  the  lung  is  balanced  and  its  elasticity  causes  it  to  collapse  and 
retract  toward  the  hilum.  In  operating  for  empyema  collapse  of  the 
lung  is  often  prevented  by  its  adhesions  to  the  chest  wall.  If  the  opening 
of  a  wound  of  the  pleura  is  not  free,  the  respiratory  movements  may  force 


THE  LUNGS  245 

the  air  into  the  subcutaneous  tissues,  producing  subcutaneous  emphysema. 
(  hvingto  the  close  contact  of  the  visceral  and  parietal  la  vers  of  the  pleura, 
the  latter  can  scarcely  be  wounded,  except  in  the  sinuses,  without  wound 
of  the  former.  Pneumothorax  or  emphysema  may  also  be  caused  by  a 
ruptured  vomica  (or  lung  cavity)  or  by  a  wound  of  the  lung  such  as  is 
sometimes  seen  in  fractured  ribs,  the  air  coming  from  the  opened  bronchi, 
etc.  see  p.  23]  ).  Some  non-penetrating  wounds  may  also  cause  such  an 
emphysema,  the  air  being  drawn  in  during  one  movement  of  respiration 
and  forced  into  the  tissues  during  another,  the  valvular  nature  of  the 
wound  preventing  its  escape.  In  hemothorax,  or  blood  in  the  pleural 
cavity,  there  is  usually  a  wound  or  lesion  of  the  lung,  but  the  blood  can 
come  in  greater  or  less  part  from  the  vessels  of  the  parietal  wound. 

THE   LUNGS. 

The  two  pyramidal-shaped  lungs  occupy  about  four-fifths  of  the 
thoracic  cavity  proper. 

Position. — Contained  in  the  two  pleural  sacs  their  apices  correspond 
in  position  to  the  domes  of  the  pleura  which  they  completely  fill.  From 
the  apices  of  the  lungs  the  anterior  borders  (Figs.  89  and  90),  which  be- 
come thin  and  sharp  about  4  cm.  (11  in.)  below  the  apices,  descend  con- 
verging! y  behind  the  sternoclavicular  joints  and  nearly  meet  behind  the 
sternum,  opposite  the  second  cartilages.  Thence  they  descend  vertically 
to  the  level  of  the  fourth  cartilages,  a  little  to  the  left  of  the  median  line. 
In  infants  the  thymus  separates  the  anterior  borders  more  widely,  the 
right  lung  barely  reaching  the  median  line,  while  the  left  only  reaches  the 
left  sternal  border  (Symington).  From  the  level  of  the  fourth  cartilages 
the  right  lung  bends  slightly  outward  to  reach  the  upper  border  of  the 
sixth  chondrosternal  junction,  while  the  left  lung  curves  sharply  outward, 
with  an  external  convexity,  across  the  fourth  space  and  the  fifth  cartilage, 
and  thence  back  nearly  to  the  inner  end  of  the  sixth  left  cartilage,  at  (lie 
lingula.  In  expiration  this  " cardiac  incisure"  may  reach  to,  or  nearly 
to.  the  apei  of  the  heart,  which  is  covered  by  the  lingula.  It  forms  the 
left  boundary  of  the  area  of  cardiac  flatness  and  the  right  border  of  the 
lingula  of  the  left  upper  lobe. 

The  level  of  the  lower  border  (Figs.  89  and  90)  is  especially  important 
for  the  diagnosis  of  certain  pulmonary  conditions.  In  (|uiet  breathing 
the  lower  border  is  at  the  upper  border  of  the  sixth  costal  cartilage  at  the 

side  of  the  sternum,  the  upper  border  of  the  seventh  rib  in  the  mammary 
line,  the  lower  border  of  the  seventh  rib  in  the  axillary  line,  the  ninth 
rib  in  the  Scapular  line,  the  upper  border  of  the  eleventh  rib  or  the  tenth 
Ipace  at  the  vertebra'.  It  will  thus  be  seen  that  the  level  <>!'  the  lung 
at  any  line  except  the  sternal  is  the  same  as  the  level  of  the  pleura  a!  the 

line  next  anteriorly  (see  p.  l'IlV     The  left  lung  is  said  to  be  longer  and 
extend  lower  than  the  right  lung,  but  the  difference  is  so  slight,  if  it  I 
that  it  i-  not  worth  considering  from  a  practical  clinical  standpoint.      In 
in   pii.ilion  the  anterior  pari     of  the  lung  n  ie  abouf   equally  with  the  ele- 
vation of  the  thoracic  wall  .    At  the  sides,  in  deep  in  ipiration,  the  lower 


246  THE  THORAX 

border  descends  about  3  to  4  cm.  (1^  in.)  (Godlee),  in  emphysema  it  is 
permanently  lower,  in  the  aged  it  is  one-half  to  one  intercostal  space 
lower,  and  in  children  the  same  distance  higher  than  in  the  adult.  The 
difference  in  level  of  the  lower  border  of  the  lung  in  extreme  expiration 
compared  with  extreme  inspiration  is  not  over  6  cm.  in  the  right  axillary 
line,  and  9  cm.  in  the  left  (Hasse).  These  borders  in  the  axillary  line 
do  not  reach  nearer  the  lower  margin  of  the  chest  than  7  and  5  cm. 
respectively.  The  posterior  border,  extending  from  the  neck  of  the  first 
rib  to  the  eleventh  rib,  is  usually  taken  to  be  the  rounded  part  occupying 
the  costovertebral  groove,  but,  as  stated  above  (see  p.  243),  it  is  better  to 
consider  it  the  ridge  bounding  the  back  of  the  groove  for  the  aorta  on 
the  left  and  the  azygos  major  vein  on  the  right.  To  this  border  is  attached 
the  ligamentum  latum,  below  the  hilum.  Normally  the  surface  of  the 
lung  is  everywhere  in  contact  with  the  parietal  pleura,  which  thus  sup- 
ports it,  and  it  is  further  held  in  position  by  its  attachment  to  the  medi- 
astinum by  means  of  the  root  of  the  lung  and  the  ligamentum  latum. 

Relations. — The  concave  base  of  the  lung  resting  on  the  diaphragm 
is  only  separated  by  the  latter  and  its  serous  coverings  from  the  abdominal 
viscera  in  contact  with  it,  liver,  stomach,  spleen,  kidneys,  suprarenals. 
Inflammation,  abscess,  and  tumors  of  these  organs,  after  penetrating  the 
diaphragm,  may  involve  the  pleurae  and  lungs,  and  vice  versa.  Liver 
abscess  is  occasionally  evacuated  through  the  lung  and  coughed  up. 
On  percussion  we  distinguish  the  lower  border  of  the  lung  on  the  right 
side  by  the  contrast  between  the  pulmonary  resonance  and  the  liver 
flatness  below  it,  and  on  the  left  side  by  the  less  marked  contrast  between 
the  tympanitic  resonance  of  the  stomach  and  the  pulmonary  resonance. 
Internally  the  heart  and  many  of  the  great  vessels  of  the  mediastinum 
are  in  relation  with  the  lungs.  The  greater  projection  of  the  heart  on  the 
inner  aspect  of  the  left  lung  inferiorly  makes  the  left  lung,  and  especially 
its  base,  narrower  than  the  right,  and  accordingly  its  bulk  and  weight  are 
less.  The  left  lung  averages  twenty  ounces,  the  right  lung  twenty-two 
ounces  in  weight,  but  the  weight  may  be  greatly  increased  by  disease. 
The  subclavian  artery  grooves  the  forepart  of  the  apex  in  a  transverse 
direction. 

The  Fissures. — The  fissures  extend  deeply  toward  the  hilum.  The 
fissure  (Figs.  89  and  90)  which  separates  the  upper  from  the  lower  lobe 
commences  on  both  sides  at  the  posterior  border  7.5  cm.  (3  in.)  below  the 
apex,  on  a  level  with  the  third  thoracic  spine  or  the  inner  end  of  the  spine 
of  the  scapula.  Thence,  sweeping  around  the  convex  surface  of  the  lung, 
it  meets  the  lower  border  in  the  mammary  line  on  the  right  side,  and  at 
the  outer  end  of  the  sixth  cartilage  on  the  left  side.  On  the  right  side  this 
fissure  crosses  the  convex  surface  somewhat  lower  than  on  the  left,  and 
from  about  its  middle,  or  where  it  crosses  the  posterior  axillary  line,  a 
second  fissure  (Fig.  89)  passes  nearly  horizontally  forward  to  the  fourth 
right  chondrosternal  junction,  separating  a  middle  lobe  from  the  upper 
lobe. 

Posteriorly,  practically  all  the  lung  above  the  level  of  the  inner  end  of 
the  spine  of  the  scapula  is  upper  lobe;  all  below  is  lower  lobe.    Laterally, 


THE  LUNGS  247 

in  the  axillary  line,  all  the  lung  above  the  fourth  rib  on  both  sides  belongs 
to  the  upper  lobe,  while  on  the  left  side  all  below  belongs  to  the  lower 
lobe,  and  on  the  right  side  from  the  fourth  to  the  sixth  rib  belongs  to  the 
middle  lobe,  all  below  the  sixth  rib  to  the  lower  lobe. 

Anteriorly,  in  the  mammary  line,  on  the  left  side  all  the  lung  above 
the  middle  of  the  fifth  space  belongs  to  the  upper  lobe,  all  below  to 
the  lower  lobe;  on  the  right  side  all  above  the  fourth  rib  belongs  to  the 
upper,  all  below  to  the  middle  lobe.  Thus  we  see  that  the  lower  lobe  is 
not  only  below  but  behind  the  upper  lobe.  It  is  in  the  posterior  part  of 
the  former  that  congestion  and  edema  in  old  people,  kept  long  supine, 
is  likely  to  lead  to  "hypostatic  pneumonia."  These  points  are  of  prac- 
tical importance  in  the  physical  examination  of  the  lungs,  especially 
when  pneumonia  or  tuberculosis  are  suspected,  for  in  the  former  the 
lower  lobe  and  in  the  latter  the  upper  lobe  are  most  often  involved. 

The  Apex. — The  apex  of  the  lung  is  a  favorite  site  for  pleural  adhesions 
a  n<  1  f(  >r  tuberculous  lesions.  The  frequency  of  adhesions  may  be  accounted 
for  by  the  fact  that  the  apex  at  all  times  fills  the  dome  of  the  pleura, 
and,  being  a  narrow  portion  of  lung  tissue,  its  motion  is  slight;  and  by 
the  fact  that  the  apex  is  frequently  the  seat  of  lesions  which  may  lead 
to  a  pleurisy.  In  proportion  to  its  bulk  the  apex  probably  expands 
as  much  as  any  other  part  of  the  lung,  and  the  prevalence  of  tuberculous 
lesions  here  is  to  be  accounted  for  by  other  factors  than  the  stagnation 
of  the  air  current  in  this  part  (see  p.  248). 

The  concave  median  surface  presents  the  oval  fissure  or  hilum,  where 
the  structures  contained  in  the  root  of  the  lungs  emerge  or  enter.  The 
upper  end  of  the  hilum  is  at  the  junction  of  the  upper  and  middle  third 
of  this  surface,  opposite  the  disk  between  the  fifth  and  sixth  thoracic 
vertebrae,  and  at  the  junction  of  the  anterior  three-fourths  with  the 
posterior  fourth  of  this  surface.  Hence  the  root  of  the  lung  is  more 
accessible  from  behind.  The  neighborhood  of  the  root  of  the  hum',  on 
account  of  the  large  vessels  here,  must  be  avoided  in  puncturing  the  lung 
with  a  needle  for  diagnosis.  This  may  be  safely  done  over  the  greater 
pari  of  the  anterior  surface  to  the  depth  of  3.5  cm.  (I  §  in.)  in  a  backward 
and   outward   direction.      In   puncturing  (lie  apical   part  from   in   front, 

through  the  first  or  second  spaces,  remember  that  die  infernal  mammary 

artery  is  a  finger's  breadth  from  the  sternum  and  the  axillary  vein  is 
8.5  cm.     '-'>\   in.)  from   the   middle  line  in   the  first  space  and    L1.5  em. 

1  |  in.  ]  in  the  second  space. 

The  Color.  The  color  of  the  lungs  changes  from  ;i  reddish  brown 
in  the  fettlS  to  a   pinkish   white  at  birth,  owing  |(,  their  insufflation  with 

air.    In  the  adult  they  are  slate-colored,  with  a  darker  mottling  of  certain 

lobules,  which  increases  with  age,  is  very  ma  iked  in  coahniners,  i-ii\, 
and  is  due  to  the  deposit  in  the  inferlobnla  r  (issue  of  ca  rhonaceoiis  par- 
ticle ab  orbed  by  tne  lymphatics.  The  specific  gravity  of  the  lungs  is 
normally  lighter  than  water,  50  thai  they  float,  bui  in  certain  diseased 
conditions  (pneumonia,  etc.)  and  in  the  fetus  thai  has  never  breathed 
ink.  This  fad  is  useful  medicolegally  to  determine  whether  an 
infanl  was  stillborn  or  born  alive.     If  the  child  has  breathed,  the  weight 


248  THE  THORAX 

of  the  lungs  also  increases  by  one-third"  (on  account  of  the  access  of 
blood),  the  size  increases,  and  the  consistency  is  altered  byaeration. 

Capacity. — While  the  capacity  of  the  lungs  after  the  deepest  inspiration 
averages  5000  c.c,  1500  c.c.  of  this  (residual  air)  cannot  be  expelled 
by  the  fullest  expiration.  The  total  capacity  minus  the  residual  air,  or 
3500  c.c,  is  the  vital  capacity  of  the  lungs,  and  is  liable  to  be  affected 
by  various  diseases  of  the  lungs.  In  quiet  breathing  1500  c.c.  of 
"reserve  air"  remain  after  expiration  in  addition  to  the  residual  air, 
and  in  inspiration  only  500  c.c.  are  breathed  in,  leaving  1500  c.c.  of 
complemented  air  to  be  inspired  by  a  forced  inspiration. 

Vessels. — The  bronchial  vessels  supply  the  mechanism  of  the  lung,  or 
the  lung  stroma.  They  anastomose  to  some  extent  with  the  pulmonary 
vessels  and  so  may  be  of  service  in  stenosis  or  closure  of  the  pulmonary 
artery,  which  is  extremely  rare.  The  pulmonary  artery  in  its  course  to  and 
through  the  lung  is  curved  with  an  upward  convexity.  From  the  convex 
surface  the  first  branch  given  off  passes  to  the  upper  lobe  and  apex. 
Solid  particles  in  the  current  which  have  a  specific  gravity  greater  than 
the  blood  tend  to  hug  the  upper  wall  and  to  pass  into  the  first  branch  given 
off  from  this  part.  Thus  they  pass  into  the  upper  lobe  and  apex.  This 
is  the  probable  explanation  of  the  more  frequent  occurrence  of  tuber- 
culosis in  the  apex,  especially  as  the  tubercles  are  first  observed  in  the 
walls  of  the  smaller  arteries  at  their  points  of  bifurcation. 

When  a  branch  of  the  pulmonary  artery  is  plugged  by  an  embolus 
the  circulation  is  stopped  in  the  area  supplied  by  it.  This  is  called  an 
infarct  and  is  wedge-shaped,  with  the  apex  at  the  embolus  and  the  base 
on  the  surface  of  the  lung,  for  such  is  the  shape  of  the  area  supplied  by 
the  vessel,  whose  circulation  is  terminal.  If  such  an  embolus  is  infective, 
an  abscess  may  result.  Only  in  the  lung  can  the  embolus  come  from  a 
systemic  vein,  so  that  the  lung  is  the  most  frequent  seat  (75  per  cent.) 
of  metastatic  pyemic  infarcts  and  abscesses. 

The  lymph  vessels  of  the  lung  empty  into  four  or  six  nodes  in  the  root 
of  the  lung  which  are  accessory  to  the  bronchial  nodes.  The  root  nodes 
are  black  from  the  pigment  absorbed  in  the  lungs.  They  are  often  dis- 
eased, and  thus  menace  the  neighboring  parts. 

In  the  bronchi  the  muscular  tissue  is  arranged  circularly,  and  by  its 
reflex  irritation  from  the  vagus,  as  in  indigestion,  or  by  direct  irritation  in 
uric  acid  or  uremic  conditions,  it  may  contract  suddenly  and  give  rise  to 
an  attack  of  spasmodic  asthma.  In  chronic  interstitial  pneumonia  the 
pull  of  the  contracting  new  tissues  draws  apart  the  walls  of  the  bronchi, 
as  these  offer  less  resistance  than  the  retraction  of  the  chest  wall.  Large 
bronchial  cavities  (bronchiectasis)  are  thus  formed,  in  which  the  fluid 
collecting  is  liable  to  decompose  and  give  rise  to  fetid  breath  and  expec- 
toration. 

The  sounds  of  breathing  are  mainly  produced  at  the  glottis  like  those 
of  the  voice.  Hence,  as  we  auscultate  them  through  the  chest  wall,  their 
loudness  varies  with  the  distance  from  the  glottis.  As  the  diameter  of 
the  tubes  and  the  volume  of  air  along  which  these  vibrations  are  carried 
diminishes  in  the  lung,  the  pitch  becomes  correspondingly  higher.    If  the 


PLATE  XXIV 


Recur,  lar.  nerve 

V.  asygo8 


Epart. 

ch  us 


I'lllm. 

veins 


]&?    m 

cuophafftt 
Thoracic  Contents  Seen  from  Behind.     (Joessel.) 


THE  LUNGS  249 

breath  sounds,  normal  in  a  given  place  (as  over  the  large  bronchi),  are 
heard  where  they  should  not  be  heard,  they  become  pathological.  The 
pathological  breath  and  voice  sounds  are  often  due  to  changes  in  the 
conducting  power  of  the  medium  through  which  the  sounds  pass  to 
reach  the  ear.  Thus  the  sounds  are  diminished  or  absent  if  they  traverse 
air  or  fluid  in  the  pleural  cavity,  while  consolidation  of  the  vesicles 
increases  the  conduction,  and  the  breath  sounds  in  the  bronchi  are 
dearly  heard  (bronchial  breathing),  the  voice  sounds  are  loud  and  seem 
close  to  the  ear  (pectoriloquy),  and  the  tremor  of  the  vocal  cords  felt  by 
the  hand  (vocal  fremitus)  is  increased.  The  normal  (vesicular)  breath 
sounds  are  also  diminished  or  lost  when  there  is  any  obstruction  or 
compression  of  the  air  passages,  immobilization  of  the  chest,  etc.  Hales 
follow  the  same  rules  as  to  loudness,  but  their  quality  varies,  some  being 
moist  and  due  to  the  bursting  of  bubbles  in  mucous  or  watery  secretion, 
others  being  dry  (crepitant)  and  due  to  the  separation  of  opposed  sur- 
faces which  were  glued  together.  They  vary  in  fineness  with  the  size  of 
the  passage  where  they  are  produced. 

The  elasticity  of  the  lung  is  one  of  its  striking  and  important  features. 
It  assists  expiration,  is  one  of  the  factors  producing  pigeon  breast  in  the 
rachitic,  explains  the  fact  that  in  rupture  or  wound  of  the  diaphragm  the 
lung  is  never  herniated  into  the  abdomen,  and  it  maintains  the  vault  of 
the  diaphragm.  If  the  lung  is  wounded  or  incised  within  the  limits  of  a 
pleural  adhesion,  subcutaneous  emphysema  may  be  produced,  but  not 
pneumo- or  hemothorax.  When  the  pleural  cavity  is  opened  through  the 
thoracic  wall,  or  through  the  lung,  the  atmospheric  pressure  within  and 
without  the  lung  is  equalized,  and  hence  it  retracts,  owing  to  its  elas- 
ticity. In  such  cases  we  have  a  serosanguineous  extravasation  and  air  in 
the  pleura]  cavity,  and  if  the  chest  wall  is  injured,  as  by  a  fractured  rib, 
subcutaneous  emphysema  is  likely  to  occur.  In  operating  on  the  thoracic 
cavity  the  collapse  of  the  lung  may  be  prevented  either  by  diminishing 
the  air  pressure  on  the  outside  or  increasing  the  pressure  within  the  lung. 
Hernia  of  the  lung,  through  a  wound  of  the  thoracic  wall,  can  only  occur 
when  the  lung  fails  to  collapse,  and  this  implies  that  the  glottis  was  closed 
;it  the  time  of  injury,  that  the  wound  was  small,  oblique,  and  valve-like, 
or  that  extensive  adhesions  bound  the  lung  to  the  chest  wall.  In  the 
latter  case  the  adhesions  would  probably  prevent  hernia.  The  gravity  of 
WOUnds  of  the  lung  depends  largely  upon  the  hemorrhage,  hence  they  are 

more  serious  near  the  large  vessels  on  the  internal  surface.     Contusion 

and    partial  rupture  of  the  lung  may  occur  without   fracture  of  the  bony 

thorax.  It  is  noteworthy  that  the  air  in  pneumothorax  seldom  contains 
germs,  or  at  least  insufficient  number  to  infect  the  extravasated  blood. 
Wounds  of  the  lung  cicatrize  rapidly  and  the  air  in  the  pleural  cavity  is 
rapidly  absorbed.     Blood  expectorated   from  the  lungs  is  necessarily 

coughed  up  and  mixed  with  air,  hence  it  is  frothy  and  bright  red.  It  is 
also  alkaline,  while  that  retched  up  from  the  stomach  is  acid  and  dark. 

Roots  of  the  Lungs  (Fig.  (.»l ).     In  the  root  of  the  lung  the  bronchus 

lux  posteriorly  with  the  artery  ami  Vein  in  front,  and  the  latter  below. 
Hence  when  an  object    is  impacted   in  the  main  bronchi  or  their  priman 


250  THE  THORAX 

divisions  they  may  best  be  reached  from  behind  by  a  posterior  thorac- 
otomy, an  opening  into  the  thorax  at  the  side  of  the  vertebrae  at  the  level 
of  the  fourth  to  the  seventh  ribs.  In  this  operation  it  is  well  to  remember 
that  the  space  between  the  tips  of  the  transverse  processes  and  the  angles 
of  ribs  varies  from  2.5  to  6  cm.  (1  to  2\  in.),  and  that  the  tips  of  the  spinous 
processes  of  the  second  to  the  eleventh  thoracic  vertebrae  correspond  to  the 
level  of  the  heads  of  the  ribs  corresponding  in  number  with  the  vertebra 
next  below  (Bryant).  The  relations  of  the  roots  of  the  lungs  are  impor- 
tant in  such  cases.  On  the  right  side  the  azygos  major  vein  is  behind  and 
arches  above  it,  to  open  into  the  superior  cava ;  while  on  the  left  side  the 
arch  of  the  aorta  is  above  and  the  descending  aorta  and  esophagus  behind 
it.  On  both  sides  the  pneumogastric  nerve  and  the  larger  or  posterior 
pulmonary  plexus  are  behind,  and  the  phrenic  nerve  and  the  smaller  or 
anterior  plexus  in  front.  Hence  the  left  side  is  more  covered  by  impor- 
tant relations  and  is  more  difficult  to  reach,  but  the  pleura  is  retracted 
with  more  difficulty  on  the  right  side,  making  it  less  easy  to  reach.  By 
stripping  back  from  the  mediastinial  side  the  pleura  covering  the  poste- 
rior aspect  of  the  root  we  expose  the  bronchi.  These  are  easily  recog- 
nizable by  touch  on  account  of  the  cartilaginous  rings,  and  may  then  be 
opened  (bronchotomy).  The  root  of  the  lung  measures  3  cm.  vertically 
and  2  cm.  anteroposteriorly;  the  right  root  is  larger,  the  left  longer. 


THE  THORACIC  PORTION  OF  THE  TRACHEA. 

This  extends  from  the  episternal  notch,  at  the  level  of  the  disk  between 
the  second  and  third  thoracic  vertebrae,  to  its  bifurcation,  opposite  the 
disk  between  the  fourth  and  fifth  thoracic  vertebra,  and  includes  about 
half  the  length  of  the  tube,  or  5.5  cm.  {2\  in.)  It  lies  in  the  superior 
mediastinum  between  the  two  pleural  sacs  and  the  vagus  nerves,  in  front 
of  the  esophagus,  and  behind  the  remains  of  the  thymus  gland,  the  left 
innominate  vein,  the  innominate  and  left  common  carotid  arteries,  and 
the  arch  of  the  aorta.  It  bifurcates  behind  the  lower  border  of  the 
aortic  arch  at  about  the  level  of  the  junction  of  the  first  and  second  pieces 
of  sternum,  or  of  the  inner  end  of  the  spine  of  the  scapula.  Hence 
abnormal  sounds  produced  at  the  tracheal  bifurcation,  or  in  the  primary 
bronchi,  can  best  be  heard  between  the  shoulders  at  this  level.  Sur- 
rounding the  bifurcation  of  the  trachea  are  twenty  to  thirty  bronchial 
lymph  nodes,  which  are  frequently  diseased  and  may  press  upon  and 
narrow  the  trachea  or  adhere  to  and  ulcerate  through  it.  Stenosis  of  the 
trachea  from  syphilitic  lesions  or  from  aneurysms  of  the  aorta  or  the 
great  vessels  are  apt  to  occur  at  its  upper  or  lower  ends,  respectively. 
Compression  of  the  trachea  is  more  serious  in  the  chest  than  in  the 
neck,  for  in  the  former  it  cannot  escape  or  avoid  the  effects  of  even 
moderate  pressure. 

Of  the  two  bronchi  the  right  is  the  larger,  so  that  the  dividing  ridge 
(carina  tracheae)  between  the  two  bronchi  lies  to  the  left  of  the  median 
line,  and  it  is  more  vertical  so  that  the  trachea  seems  to  lead  more  directly 


THE  PERICARDIUM  251 

into  the  right  bronchus.  Hence,  and  by  reason  of  the  greater  intake  of 
air,  foreign  bodies  are  more  likely  to  pass  into  the  right  bronchus,  and,  as 
we  have  already  seen,  this  is  the  side  most  safely  exposed  from  behind. 
If  small  enough,  they  may  pass  on  into  the  secondary  bronchi  with  the 
same  inspiration  with  which  they  passed  the  glottis.  Such  foreign  bodies 
cause  a  mechanical  obstruction  of  the  air  passages  and  also  a  reflex 
spasm  of  the  glottis,  together  with  cough,  dyspnea,  alteration  of  voice, 
etc.  Foreign  bodies  at  or  a  little  below  the  bifurcation  of  the  trachea 
may  often  be  removed  by  forceps  introduced  through  a  low  tracheotomy 
opening,  or  they  may  be  spontaneously  expelled  by  a  fit  of  coughing 
through  the  open  tracheal  wound  or  through  the  larynx.  They  may 
also  be  removed,  even  from  the  secondary  bronchi,  by  the  aid  of  the 
bronchoscope.  In  other  cases  they  have  caused  an  abscess  of  the  lung, 
or  have  ulcerated  through  the  bronchus  and  been  discharged  through  an 
abscess  at  the  back,  adhesions  having  shut  off  the  pleura.  Mr.  Godlee 
records  a  case  where  a  head  of  rye  so  escaped. 

The  course  of  the  bronchi  is  toward  the  hindpart  of  the  lower  surface 
of  the  lung  (i.  c,  behind  the  axis  of  the  lung).  Hence,  of  the  ventral  and 
dorsal  branches  given  off  by  the  bronchi,  the  former  are  much  the  larger. 
The  relation  of  the  left  stem  bronchus  to  the  aortic  arch,  which  arches 
above  and  then  behind  it,  explains  the  frequent  pressure  of  aneurysms 
on  this  bronchus.  The  close  relation  of  the  aortic  arch  to  the  bifurca- 
tion of  the  trachea  explains  the  sign  known  as  "tracheal  tugging"  elicited 
with  the  patient  erect,  the  chin  elevated,  and  the  mouth  closed,  by  steady 
and  gentle  upward  traction  on  the  cricoid.  If  pulsation  is  distinctly 
transmitted  to  the  hand,  aneurysm  or  dilatation  of  the  aorta  is  indicated. 
The  right  undivided  bronchus  averages  2.5  cm.  (1  in.)  in  length,  the 
left  5  cm.  (2  in.).  The  latter  enters  its  lung  2.5  cm.  (1  in.)  lower  than 
the  right,  opposite  the  sixth  thoracic  vertebra. 


THE  PERICARDIUM. 
The  pericardium,  like  the  pleura,  is  a  closed  invaginated  sac.     But 

it  is  more  complicated  than  the  pleura,  for  instead  of  one  there  are  seven 

reflections,  which  connect  the  parietal  and  viscera]  layers  and  form 
more  or  less  complete  sheaths  around  the  great  vessels  at  the  base  of  the 
heart.  Between  these  sheaths  there  are  a  number  of  pouches  or  sinuses, 
of  which  the  largest  is  the  great  or  transverse  sinus,  between  the  auricles 
behind  and  the  tubular  sheath  of  the  aorta  and  pulmonary  artery  in 

front.     An  encapsulated  effusion  may  occur  in  this  sinus,  the  pressure  of 

which  i-  exerted  principally  upon  the  thin-walled  superior  vena  cava, 
without  giving  evidence  of  pericarditis  with  effusion.  Sinuses  like  those 
of  the  pleura  exist  only  to  a  slight  extent  al  the  reflection  of  the  pericar- 
dium from  the  diaphragm.     The  tubular  pericardial  sheath  common  to 

the  aorta  and  pulmonary  artery  i-.  the  only  complete  one  i »ng  the  seven. 

It  covers  the  proximal  ;!.7  cm.  1 1 J  in.  of  the  e  ve  jels,  which  is,  therefore, 
within  the  pericardial  sac.     The  parietal  serous  layer  is  reinforced  exter- 


252  THE  THORAX 

nally  by  a  fibrous  layer,  which  blends  with  the  outer  coat  of  the  great 
vessels  beyond  their  serous  investments  and  becomes  continuous  above 
with  the  deep  cervical  fascia.  Hence  the  pericardium  is  connected  with 
the  respiratory  muscles  of  the  neck,  like  the  omohyoid,  above,  as  well  as 
with  the  diaphragm  below,  so  that  in  a  full  inspiration  it  is  pulled  upon 
from  both  directions  and  made  tense  and  resistant  to  the  pressure  on  the 
heart  by  the  inflated  lungs. 

The  elasticity  of  the  parietal  pericardium  allows  it  to  be  stretched  to 
double  its  size,  so  as  to  contain  twelve  to  eighteen  ounces  in  case  of  acute 
pericardial  effusion,  or  even  up  to  three  pints  in  chronic  cases.  It  is  only 
when  the  pericardium  is  greatly  distended  that  the  pressure  affects  the 
heart,  especially  in  diastole,  and  may  cause  a  fatal  result.  As  the  shape 
of  the  pericardium  is  cone-  or  pear-shaped,  with  the  base  below  on  the 
diaphragm  and  the  apex  above,  this  is  the  shape  of  pericardial  effusions, 
while  in  cardiac  hypertrophy  or  dilatation  the  long  diameter  is  directed 
transversely.  In  pericardial  effusion  the  dulness  reaches  beyond  the 
apex  beat,  or,  if  the  effusion  is  extensive,  the  apex  beat  may  not  be  per- 
ceptible. When  the  sac  is  but  partly  full,  the  fluid,  and  with  it  the  area  of 
dulness,  may  shift  its  position  with  that  of  the  body,  and,  as  it  presses 
upon  the  bronchi  in  the  reclining  position,  the  patient  breathes  more 
easily  in  the  upright  posture.  By  excessive  pericardial  effusion  the  lungs, 
especially  the  left,  are  pushed  aside  and  compressed  laterally,  increasing 
the  area  of  heart  dulness,  the  diaphragm,  liver,  and  stomach  are  displaced 
downward,  the  lower  two-thirds  of  the  sternum  and  the  corresponding 
left  cartilages  and  spaces  are  bulged  forward,  and  the  trachea,  left  bron- 
chus, and  esophagus  are  compressed  posteriorly,  giving  rise  to  cough, 
dyspnea,  and  dysphagia. 

Paracentesis  of  the  pericardium  is  usually  done  in  the  fifth  left  space  2.5 
cm.  (1  in.)  from  the  sternum.  If  a  point  nearer  the  sternum  is  taken  there 
is  danger  of  wounding  the  internal  mammary  artery  (p.  233),  though  if 
an  incision  is  used  and  not  a  puncture,  we  may  go  close  to  the  sternum. 
Unless  the  pleura  has  been  pushed  aside  by  the  effusion,  the  trocar  will 
puncture  two  layers  of  it  2.5  cm.  (1  in.)  from  the  sternum.  The  puncture 
may  preferably  be  made  in  the  sixth  left  space  with  less  danger  of  wounding 
the  heart,  and  if  made  close  to  the  sternum  the  danger  of  wounding  the 
mammary  artery  is  avoided.  Some  advise  puncturing  on  the  right  side 
of  the  sternum  in  the  fourth  or  fifth  space,  where  the  distended  pericar- 
dium also  bulges,  on  the  supposition  that  there  is  less  danger  of  punctur- 
ing the  heart  itself. 

Normally  the  pericardium  is  in  direct  relation  with  the  anterior  parietes 
(sternum)  only  (1)  over  a  small  area  at  its  upper  end,  where  it  is  reflected 
onto  the  aorta,  and  (2)  over  a  triangular  area  at  the  lower  end  of  the  ster- 
num, where  the  pleura?  diverge,  and  where,  by  a  trephine  opening,  the 
pericardium,  uncovered  by  pleura,  may  be  reached.  No  true  ligaments, 
only  loose  connective  tissue,  bind  the  pericardium  to  the  back  of  the  ster- 
num. Whereas  in  front  and  laterally  the  pericardium  is  largely  covered 
by  pleura,  the  phrenic  nerves  intervening  laterally,  posteriorly  it  forms 
the  anterior  boundary  of  the  posterior  mediastinum,  and  is  in  direct 


THE  HEART  253 

relation  with  the  thoracic  aorta,  azygos  veins,  thoracic  duct,  and  esopha- 
gus, which  pericardial  effusion  may  press  upon,  especially  in  the  supine 
position. 

THE  HEART. 

( )n  opening  the  pericardium  in  front  we  see  the  anterior  or  sterno- 
costal surface  of  the  heart,  comprising  a  part  of  the  two  ventricles,  the  right 
auricle  and  its  appendage,  and  the  tip  of  the  left  auricular  appendage. 
Of  these  parts,  the  right  ventricle  presents  the  greater  area,  hence  it  is 
most  often  wounded  in  wounds  of  the  heart.  As  the  right  ventricle  is 
one-third  the  thickness  of  the  left,  we  can  tell  the  two  apart  by  the  feeling. 
The  left  ventricle  is  thinnest  at  the  apex  and  thickest  at  the  junction  of  its 
upper  and  middle  thirds.  The  anterior  and  posterior  interventricular 
grooves  lie  near  the  left  and  inferior  borders  respectively,  and  meet  and 
are  continuous  to  the  right  of  the  apex. 

In  front  the  heart  is  overlapped  by  the  pleurae,  except  behind  the  lower 
end  of  the  sternum,  as  described  above  (p.  242),  and  by  the  thin  margins 
of  the  lungs,  except  for  this  area  between  the  pleura?  and  that  of  the  car- 
diac incisure,  which  corresponds  to  the  area  of  cardiac  flatness.  The  latter 
corresponds  to  a  triangular  area  bounded  below  by  the  lower  border  of  the 
heart,  on  the  right  by  the  left  sternal  margin  up  to  the  upper  border  of 
the  fourth  cartilage,  and  on  the  left  by  a  line  curved  outward  from  the 
latter  point  to  the  lower  border  near  the  apex.  A  circle  5  cm.  (2  in.)  in 
diameter,  with  its  centre  midway  between  the  nipple  and  the  sterno- 
xiphoid  junction,  would  also  approximately  represent  this  area.  Emphy- 
sema may  cause  this  area  to  be  much  diminished. 

The  anterior  or  sternocostal  surface  is  the  only  one  accessible  to  clinical 
investigation  by  percussion,  etc.  Besides  the  area  of  cardiac  flatness,  we 
have  the  area  of  cardiac  dvlness,  which  corresponds  to  that  part  of  the 
anterior  surface  overlapped  by  the  lungs  and  sternum.  Owing  to  the  modi- 
fication of  the  percussion  note  by  the  sternum  and  the  margin  of  the  right 
lung,  the  right  border  of  the  heart  cannot  be  definitely  determined.  As 
the  heart  dulness  merges  into  that  of  the  liver  below,  the  lower  border 
cannot  be  determined  by  percussion,  but  may  be  constructed  by  con- 
tinuing the  lower  border  of  the  right  lung  through  the  sternoxiphoid 
junction    to   the  apex   of   the   heart.     The  left  border  alone   is   tolerably 

ible  to  percussion,  and  by  this  we  determine  changes  in  the  size 

and  position  of  the  heart. 

Laterally  tin-  heart  is  in  contact  with  the  lungs,  separated  by  the  peri- 
cardium, pleura-,  and  phrenic  nerves.  It  encroaches  more  on  the  left 
side  of  the  chest  ;i 1 1<  1  the  left  lung,  SO  that  two-thirds  of  the  heart  are  on 
dc.  Only  the  right  auricle  and  a  small  part  of  the  left  auricle  and 
right  ventricle  arc  on  the  righi  side  of  a  median  sagittal  plane.  The 
auricles  lie  above,  behind,  and  to  the  right  of  the  mass  of  the  ventricles, 
and  correspond  to  the  sixth,  seventh,  and  eighth  thoracic  vertebra'. 
Hut  between  the  heart  and  the  thoracic  spine  lies  the  posterior  medi- 
astinum, containing  the  esophagus,  thoracic  dud,  aorta,  and  azygos  veins, 


254  THE  THORAX 

The  apex,  belonging  solely  to  the  left  ventricle,  is  directed  downward, 
forward,  and  to  the  left,  and  strikes  the  chest  wall  in  systole  in  the  fifth 
space  8  cm.  (3j  in.)  from  the  median  line,  or  5  cm.  (2  in.)  below  and 
2.5  cm.  (1  in.)  internal  to  the  male  nipple.  The  apex  beat  may  be  likened 
to  the  recoil  of  a  gun,  due  to  the  discharge  of  blood  into  the  aorta.  It  also 
depends  upon  the  lengthening  of  the  aorta  from  the  blood  entering  it  at 
the  cardiac  systole. 

Topography. — The  heart,  as  projected  onto  the  chest  wall,  may  be 
mapped  out  as  a  triangular  figure,  whose  upper  truncated  angle  repre- 
sents the  base  of  the  heart,  from  which  the  great  vessels  are  given  off. 
This  is  represented  by  a  line  across  the  sternum  at  the  level  of  the  upper 
borders  of  the  third  cartilages,  somewhat  higher  on  the  left  than  on  the 
right,  and  projecting  12  mm.  Q  in.)  to  the  right  and  nearly  2.5  cm.  (1  in.) 
to  the  left  of  the  sternum.  The  lower  border,  margo  acutus,  formed  by 
the  right  ventricle,  is  drawn  from  the  apex  to  the  junction  of  the  sixth 
(or  seventh)  right  costal  cartilage  with  the  sternum,  crossing  the  sternum 
near  the  costoxiphoid  junction.  This  line  is  nearly  horizontal  behind 
the  sternum,  slightly  convex  downward  to  the  left  of  it.  The  left  border, 
margo  obtusus,  formed  by  the  left  ventricle,  and  the  right  border,  formed 
by  the  right  auricle,  are  completed  by  lines  convex  laterally,  which  con- 
nect the  left  and  right  ends  of  these  two  lines,  representing  the  base 
and  the  lower  border.  The  right  border  projects  one  to  two  fingers' 
breadth  from  the  right  sternal  margin,  or  3.7  cm.  (1J  in.)  from  the 
middle  of  the  sternum  opposite  the  fourth  space. 

The  auriculoventricular  groove  runs  from  the  third  left  to  the  sixth 
(or  seventh)  right  chondrosternal  junction.  The  pulmonary  orifice  is  the 
most  superficial.  It  lies  behind  the  sternal  end  of  the  left  third  costal 
cartilage,  but  the  sound  of  the  closure  of  the  valve  is  transmitted  upward 
with  the  blood  stream  and  is  heard  most  plainly  in  the  second  left  space, 
close  to  the  sternum.  The  aortic  orifice  is  a  little  below  and  to  the  right 
of  the  latter,  behind  the  left  half  of  the  sternum,  opposite  the  third  space. 
The  mitral  orifice  is  just  to  the  left  of  and  behind  the  latter,  behind 
the  left  border  of  the  sternum,  and  opposite  the  third  space  or  the 
fourth  cartilage.  Notwithstanding  the  close  proximity  of  these  two 
most  important  valves  of  the  left  heart,  there  is  clinically  no  difficulty 
in  distinguishing  their  respective  sounds,  for  they  are  transmitted  in  the 
line  of  the  blood  stream,  so  that  the  sound  of  the  mitral  closure  is  best 
heard  near  the  apex  of  the  heart,  that  of  the  aortic  at  the  sternal  end  of 
the  second  right  intercostal  space.  The  points  of  greatest  intensity  of 
the  valvular  sounds  are  much  more  superficial  than  the  valves  themselves, 
especially  the  mitral  valve,  which  lies  farthest  posteriorly,  behind  and  a 
little  to  the  left  of  the  aortic  valve.  The  tricuspid  valve  lies  behind  the 
middle  of  the  sternum  about  the  level  of  the  fourth  space. 

The  first  sound  of  the  heart  occurs  during  ventricular  contraction 
(systole),  and  is  due  to  the  closing  of  the  mitral  and  tricuspid  valves  and 
perhaps  to  the  impulse  of  the  apex  beat.  The  second  sound  is  due  to  the 
closing  of  the  aortic  and  pulmonary  valves,  during  the  filling  of  the 
auricles    and    ventricles    (diastolic).      Of    the    pathological  sounds  or 


PLATE  XXV 


FIG.  92 


CALENDS 
ANTICUS 


RIGHT 

INNOM. 

VEIN 


RIGHT 

AURIC 

APPENDI) 


LEFT 

INNOM. 
VEIN 


ULMONARY 

ARTERY 
EFT 
URIC. 
PPENDIX 


EFT 

ENTRICLE 


MAMMARY 
LINE 


Relation  of  Heart  and  Great  Vessels  to  the  Anterior  Chest  Wall. 

(Joessel.) 


THE  HEART  255 

murmur*,  one  heard  before  the  first  sound  (presystolic)  is  due  to  a  stenosis 
of  one  of  the  auriculoventricular  valves,  which  makes  the  passage  of  blood 
difficult.  A  murmur  heard  with  the  first  sound,  or  with  the  radial 
pulse  (systolic),  is  due  to  insufficiency  with  reversed  flow  through  the 
mitral  (or  tricuspid)  valve,  or  to  stenosis  of  the  aortic  (or  pulmonary) 
valve.  One  heard  with  the  second  sound  (diastolic)  is  due  to  a  regurgi- 
tation at  the  aortic  (or  pulmonary)  valve.  The  murmurs  of  aortic  and 
mitral  insufficiency  are  the  most  common;  90  per  cent,  of  all  cases  of 
disease  of  the  valves  occur  in  those  of  the  left  side,  for  more  work  is 
required  of  this  side,  with  the  danger  of  greater  strain. 

Displacements  of  the  Heart. — The  position  of  the  heart  varies 
slightly  with  its  systole  and  diastole  and  with  the  position  of  the  body. 
In  children  the  apex  is  often  higher  (fourth  space),  in  the  aged  lower, 
(sixth  space) ,  than  the  position  given  above.  The  heart  is  elevated  in  case 
of  ascites,  tympanites,  or  tumors  of  the  abdomen  which  raise  the  dia- 
phragm, and  depressed  in  case  of  effusion  into  the  pleural  cavity,  emphy- 
sema, large  aortic  aneurysm,  mediastinal  tumors,  and  cardiac  hyper- 
trophy and  dilatation  (left  ventricle).  If  the  effusion  is  on  one  side  only, 
the  heart  is  displaced  to  the  opposite  side.  Effusions  on  the  left  side 
may  displace  the  apex  to  or  beyond  the  right  margin  of  the  sternum 
and  dislocate  the  heart  to  such  an  extent  as  to  disturb  the  circulation. 
The  heart  may  also  be  pulled  to  either  side  by  a  contracting  lung  or 
pleural  adhesion.  The  descent  of  the  heart  in  inspiration — about  2.5  cm. 
(1  in.) — is  not  as  great  as  it  is  made  to  appear  by  the  elevation  of 
the  ribs  in  front  of  it.  In  cases  of  transposition  of  the  viscera  the  apex 
beat  is  found  on  the  right  side,  and  the  position  of  the  heart  is  corre- 
spondingly altered.  The  heart's  position  is  affected  by  its  enlargement, 
which  causes  lateral  displacement,  as  a  rule.  This  enlargement  is  usually 
at  first  of  the  nature  of  a  dilatation,  and  then  the  walls  begin  to  thicken 
or  hypertrophy  to  compensate  for  the  dilatation.  Hence,  for  instance, 
an  aortic  obstruction,  that  may  be  the  cause  of  the  dilatation,  may  be  of 
comparatively  little  importance  if  there  is  compensatory  hypertrophy 
of  the  left  ventricle.  The  ill  effects  on  the  heart  in  valvular  heart  disease 
always  extend  in  the  opposite  direction  to  that  of  the  blood  stream. 

Increased  resistance  and  distention  cause  dilatation,  and  increased 
work,  to  overcome  the  resistance,  causes  hypertrophy  of  the  heart  as 
of  any  other  muscle.  The  increased  resistance  is  most  often  due  to 
arteriosclerosis,  increased   arterial   tension,  and    valvular  disease   of   the 

heart. 

The  right  mid  left  coronary  arteries  supplying  (lie  bear!  run  in  the 
auriculoventricular  and  interventricular  grooves.  Those  in  (he  grooves 
on  tin'  anterior  surface  are  especially  exposed  to  injury  in  wounds  of  the 
heart.    There  is  no  direct  anastomosis  between  the  branches  of  these 

.      Atheroma  of  these  arteries  causes  a    poor  blood  supply  of  the 

heart,  which  may  result  iii  tatty  or  fibroid  degeneration  of  the  heart 
muscle,  or  iii  angina  pectoris.    These  changes  in  the  heart  muscle  pre- 

«li  po  e  to  in jilurr  of  the  heart,  often  from  some  strain  or  injury.  This 
OCCUrs  iii  the  order  of   frequency  in  the  right    auricle,  left    ventricle,  let', 


256  THE  THORAX 

auricle,  etc.,  owing  to  the  relative  weakness  or  the  greater  tendency  to 
degeneration  of  the  myocardium.  An  embolus  in  one  of  the  coronary 
arteries  may  cause  sudden  death  from  paralysis  of  the  heart  muscle. 

The  size  of  the  heart  is,  roughly  speaking,  that  of  the  closed  fist;  the 
weight  varies  greatly,  averaging  266  to  292  grams.  The  size  and  weight 
of  the  heart  increase  up  to  advanced  life,  and  are  one-sixth  less  in  the 
female.  A  physiological  hypertrophy,  especially  of  the  left  ventricle, 
occurs  in  pregnancy. 

Wounds  of  the  Heart. — Wounds  of  the  heart  most  often  involve  the 
anterior  surface,  and  hence  concern  the  right  auricle  and  ventricle 
and  the  left  coronary  artery  and  its  accompanying  vein,  in  the  anterior 
interventricular  groove.  Wounds  in  the  third,  fourth,  and  fifth  spaces 
close  to  the  right  of  the  sternum  are  liable  to  injure  the  right  auricle, 
those  in  the  same  spaces  to  the  left  of  the  sternum  the  right  ventricle. 
The  superior  vena  cava  may  be  wounded  by  a  stab  wound  in  the  first 
or  second  right  interspace  close  to  the  sternum.  Wounds  of  the  auricles 
are  more  serious  and  more  rapidly  fatal  than  those  of  the  ventricles, 
owing  to  the  thicker  walls  of  the  latter  and  their  capacity  to  contract  and 
prevent  the  escape  of  blood.  For  a  similar  reason  wounds  of  the  right 
ventricle  are  more  serious  than  those  of  the  left.  Wounds  of  the  ven- 
tricles may  be  followed  by  little  or  no  hemorrhage,  owing  to  the  contrac- 
tion of  the  muscle  fibers,  which  run  in  all  directions,  and  the  resulting 
closure  of  the  wound.  Owing  to  the  position  of  the  pleura  and  its  relation 
to  the  pericardium,  a  wound  of  the  normal  heart,  unless  it  penetrates 
the  sternum  at  certain  points,  must  also  pierce  the  pleura,  hence  blood 
is  apt  to  be  found  in  the  left  (more  rarely  in  the  right)  pleural  cavity. 
Wounds  of  the  normal  heart,  except  over  the  area  of  cardiac  flatness, 
involve  also  the  anterior  margin  of  the  lung,  hence  air  may  escape  into 
the  pericardial  as  well  as  into  the  pleural  cavity,  and  the  blood  is  frothy. 
Wounds  of  the  heart  are  not  necessarily  fatal,  and  fatal  wounds  are  not 
as  instantly  fatal  as  commonly  supposed.  If  death  occurs  at  once,  it  is 
usually  due  to  interference  with  the  heart's  action  by  the  presence  of  blood 
which  has  escaped  into  the  pericardium,  and  not  to  the  effect  of  the  injury 
on  the  cardiac  nerve  centres.  Patients  with  apparently  fatal  cardiac 
injuries  have  lived  for  some  time,  and  others  have  survived  to  die  of  other 
causes.  In  a  few  cases  the  foreign  body  causing  the  injury  has  been  found 
on  postmortem  encapsulated  within  the  heart  muscle.  Punctured  wounds 
of  the  ventricle,  especially  of  the  left  ventricle,  may  be  recovered  from. 
Needles  have  not  infrequently  been  found  embedded  in  the  heart  muscle, 
having  worked  their  way  there  from  a  nearby  situation.  Operations 
for  cardiac  injuries  afford  a  better  prognosis  than  expectant  treat- 
ment. Of  reported  operations  for  wound  of  the  heart,  40  per  cent,  have 
recovered.  The  heart  is  exposed  by  dividing  the  costal  cartilages  from 
the  sixth  to  the  third  close  to  the  sternum  and  turning  the  flap  of  chest 
wall  back  to  the  left.  The  pleura  is  separated  from  within  outward  from 
the  pericardium,  which  may  then  be  opened.  Through  such  a  wound 
cardiac  massage  to  resuscitate  desperate  cases  of  syncope  during  anes- 
thesia has  been  used  of  late. 


THE  AORTA  257 


THE  AORTA. 


The  first  or  ascending  portion  of  the  aorta  extends  upward,  forward, 
and  to  the  right  in  the  axis  of  the  heart.  It  lies  behind  the  sternum 
and  passes  from  the  aortic  orifice,  behind  the  left  half  of  that  bone, 
opposite  the  third  space,  to  the  upper  border  of  the  right  second  chondro- 
sternal  junction.  It  reaches  to  within  about  1  cm.  of  the  root  of  the 
innominate  artery, and  lies  within  the  pericardial  sac, covered  by  the  sheath 
of  the  serous  pericardium  common  to  it  and  the  pulmonary  artery.  Hence 
an  aneurysm,  of  this  part,  before  it  attains  a  large  size,  very  commonly 
bursts  into  the  pericardium,  causing  sudden  death. 

The  relations  of  the  aorta  are  of  importance  in  connection  with  the 
pressure  symptoms  of  aneurysm  of  its  different  parts.  Aneurysm,  so 
common  in  the  aorta  when  its  walls  are  affected  by  disease,  is  most  likely 
to  involve  the  ascending  part,  for  this  is  not  strengthened,  like  the  arch, 
by  the  fibrous  layer  of  the  pericardium  blending  with  it.  Moreover,  it  is 
the  first  part  to  receive  the  impulse  of  the  cardiac  systole.  This  impulse 
is  felt  especially  along  its  right  anterior  aspect,  where  there  is  a  normal 
bulging  of  the  wall,  the  great  sinus  of  the  aorta,  from  which  the  current 
is  reflected,  as  it  were,  toward  the  left  into  the  arch.  Aneurysm  of  the 
ascending  portion  usually  bulges  to  the  right  and  forward.  Hence  it 
presses  on  the  superior  cava  on  the  right,  causing  congestion  of  the  head, 
upper  extremities,  and  chest  wall,  which  may  result  in  lividity,  swelling, 
and  edema  of  these  parts,  and  in  dizziness  and  headache.  It  presses  on 
the  sternum  in  front,  from  which  it  is  normally  separated  by  the  over- 
lapping right  lung  and  the  remains  of  the  thymus  gland.  The  pulsating 
tumor  first  appears  in  the  second  right  space,  but  after  erosion  of  the 
sternum  this  and  the  upper  right  cartilages  may  bulge  forward.  If  the 
tumor  is  directed  backward  it  may  press  upon  the  right  pulmonary  artery, 
which  lies  behind  it,  or  on  the  right  bronchus  behind  the  artery,  causing  a 
deficient  blood  and  air  supply  to  the  right  lung  and  consequent  dyspnea. 
Again,  the  aneurysm  may  start  from  one  of  the  .sinuses  of  Valsalva, 
usually  the  right  or  anterior  one,  as  the  regurgitation  of  blood  after 
systole  occurs  particularly  here.  Such  a  tumor,  usually  sacculated, 
projects  chiefly  forward  and  to  the  right,  pressing  on  the  pulmonary 

artery  in  front  and  the  right  auricle  and  superior  vena  cava  on  the  right. 
The  great   sinus  of   the   ascending  aorta   projects   a    slight    and    varying 

degree  to  the  right  of  the  sternum,  depending  partly  on  the  breadth  of 
the  sternum,  and  might  be  wounded  in  the  right  second  space. 
The  Arch  of  the  Aorta.     The  arch  of  the  aorta  is  badly  named  the 

transverse   portion   of  the  arch,   for  its  principal  direction   is  backward, 

from  about  6  iimi.    5  in.)  behind  the  sternum,  at  the  second  right  chon- 

drOSternal    junction,   to  the   left   side  of  the  body  of  the   fourth    thoracic 

vertebra.  Its  transverse  course  corresponds  only  to  about  the  width  of 
the  iternum.  The  downwardly  directed  concavity  or  lower  border  cor- 
responds to  the  junction  of  the  manubrium  and  body  of  the  sternum. 
1 1  i    also  concave  to  the  right  and  posteriorly.     Its  convexity  or  upper 

17 


258  THE  THORAX 

border  corresponds  to  the  level  of  the  third  thoracic  spine,  the  middle  of 
the  first  costal  cartilages,  the  middle  of  the  manubrium,  or  a  point  about 
2.5  cm.  (1  in.)  below  the  episternal  notch.  In  feeble  and  small-chested  per- 
sons it  may  reach  nearly  to  the  top  of  the  sternum,  or  in  big-chested  men 
it  may  occasionally  lie  as  much  as  4  to  6  cm.  (1|  to  2-J  in.)  below  it.  It  is 
covered  in  front  by  the  margins  of  the  right  and  left  pleura?  and  lungs, 
and  between  their  diverging  margins  by  the  remains  of  the  thymus 
gland.  Toward  the  left  side  the  left  vagus  and  phrenic  nerves  cross  in 
front  of  it.  The  left  recurrent  laryngeal  nerve  arches  beneath  and  then 
behind  it,  just  to  the  left  of  the  remains  of  the  ductus  arteriosus,  which 
connects  the  arch  inferiorly  with  the  angle  of  bifurcation  of  the  pulmo- 
nary artery,  or  the  root  of  its  left  branch.  The  root  of  the  left  lung,  includ- 
ing the  left  bronchus,  pulmonary  artery,  etc.,  lies  below  it.  Behind  it  is 
the  lower  end  of  the  trachea,  just  above  or  at  its  bifurcation,  the  esopha- 
gus, thoracic  duct,  and  the  left  recurrent  laryngeal  nerve.  Its  upper 
border  is  overlapped  by  the  left  innominate  vein,  which  covers  the  roots 
of  its  three  branches  which  are  given  off  above,  from  its  convexity. 

A  consideration  of  these  relations  will  indicate  the  pressure  symptoms 
of  an  aneurysm,  which  depend  upon  its  position  and  the  direction  of 
its  extension.  The  most  common  situation  is  on  the  posterior  or  right 
aspect,  where  it  may  press  upon  the  trachea,  causing  dyspnea,  cough,  and 
harsh  breathing,  and  on  the  left  recurrent  laryngeal  nerve,  paralyzing  the 
left  vocal  cord,  altering  the  voice  and  so  simulating  laryngitis  that  trache- 
otomy has  sometimes  been  done.  Owing  to  its  pressing  more  heavily 
upon  the  trachea  in  the  reclining  position,  the  patient  may  be  unable  to 
lie  down  with  comfort.  Extending  farther  backward  it  may  press  upon  the 
esophagus,  causing  dysphagia  and  simulating  esophageal  stricture,  upon 
the  thoracic  duct,  causing  inanition,  or  upon  the  sympathetic  nerve,  causing 
dilatation  of  the  pupil  from  irritation,  and  then  contraction  of  the  pupil 
from  paralysis  of  the  ciliospinal  fibers.  Extension  forward  would  involve 
the  sternum,  cause  its  erosion,  and  give  rise  to  a  pulsating  bulging  tumor, 
or  press  upon  the  left  vagus  or  phrenic  nerves.  In  case  of  extension  down- 
ward the  pressure  may  impede  the  circulation  through  the  pulmonary 
artery,  and  especially  its  left  branch,  causing  dyspnea  or  even  cyanosis 
from  the  scanty  oxidation  of  the  blood.  It  may  obstruct  the  left  bronchus, 
causing  cough,  dyspnea,  and  left-sided  harsh  and  diminished  breathing, 
or  it  may  affect  the  left  recurrent  laryngeal  nerve.  Upward  extension 
of  the  tumor  causes  pressure  on  the  left  innominate  vein,  resulting  in 
serious  congestion  of  the  left  side  of  the  head  and  neck  and  the  left  upper 
extremity,  or  upon  one  or  more  of  the  primary  branches  of  the  aorta, 
compressing  or  even  obliterating  them,  and  causing  inequality  of  the 
carotid  or  radial  pulses  on  the  two  sides,  or  absence  of  them,  especially 
on  the  left  side. 

The  tumor  may  extend  up  into  the  root  of  the  neck,  resembling 
aneurysm  of  the  innominate,  left  carotid,  or  subclavian  arteries,  and  cause 
difficulty  in  diagnosis.  Aneurysms  of  the  ascending  aorta  and  the  arch 
of  the  aorta  are  liable  to  lower  the  heart  and  to  disturb  the  heart's  action 
by  pressure  upon  the  cardiac  plexuses.    They  may  rupture  into  any  of 


THE  AORTA  259 

the  cavities  or  hollow  tubes  with  which  they  are  in  contact,  causing 
a  sudden  fatal  hemorrhage.  The  percussion  note  may  be  dull  over  a 
considerable  area,  owing  to  displacement  of  the  lungs  laterally. 

Most  descriptive  text-books  speak  of  a  short  third  or  descending  por- 
tion of  the  arch,  but  there  is  no  sufficient  reason  for  separating  this  from 
the  descending  thoracic  aortic,  which  extends  from  the  fourth  thoracic 
vertebra  to  the  aortic  orifice  of  the  diaphragm,  opposite  the  twelfth 
vertebra  and  slightly  to  the  left  of  the  median  line  (Joessel).  Superiorly 
it  lies  to  the  left,  interiorly  in  front  of  the  thoracic  .spine,  superiorly  to  the 
left  and  interiorly  behind  and  to  the  right  of  the  esophagus,  and  superiorly 
to  the  left  and  at  its  lower  part  in  front  of  the  thoracic  duct.  Furthermore, 
it  passes  behind  the  root  of  the  left  lung,  grooves  this  lung  just  in  front 
of  its  posterior  border,  and  lies  behind  the  pericardium  and  to  the  left 
of  the  vena  azygos  major.  Aneurysm  of  this  part  may  press  upon  and 
obstruct  any  of  the  above-mentioned  parts,  erode  the  spine  and  the 
vertebral  ends  of  the  left  middle  ribs,  cause  pressure  upon  and  neuralgia 
of  the  corresponding  left  thoracic  nerves,  and  bulge  posteriorly  to  the  left 
of  the  spine  as  a  pulsating  tumor,  sometimes  of  enormous  size.  It  may 
even  cause  compression  of  the  cord  and  paralysis.  It  may  eventually 
rupture  on  the  surface  or  into  the  esophagus,  left  bronchus,  pericardium, 
pleura,  or  posterior  mediastinum. 

Variations. — The  arch  of  the  aorta  is  liable  to  occasional  variations 
in  its  position  and  direction,  with  or  without  transposition  of  the  vis- 
cera, and  to  frequent  variations  in  the  number  and  arrangement  of  its 
primary  branches.  These  variations  may  decrease  the  number  of  pri- 
mary branches  to  two,  or  increase  them  to  four,  five,  or  six.1  These 
anomalies  are  to  be  explained  by  abnormalities  in  the  embryonic  develop- 
ment of  these  parts  from  the  ventral  and  dorsal  stems  and  the  branchial 
vessels.  The  only  variation  of  much  surgical  interest  is  the  origin  of  the 
carotid,  usually  the  left,  from  the  innominate  stem  of  the  opposite  side,  in 
which  cases  it  may  cross  the  trachea  so  as  to  be  in  danger  of  injury  in 

a  low  tracheotomy.     Not  infrequently  the  right  subclavian  arises  from 

the  left  end  of  the  arch  and  passes  behind    the  trachea  and   esophagus  to 

reach  its  normal  position. 

The  innominate  and  left,  common  carotid,  given  oil'  immediately  behind 
the  middle  of  the  manubrium,  mount  thence  to  the  right  and  left  sterno- 
clavicular joints,  the  former  artery  dividing  opposite  die  upper  border  of 

tin-  right   joint.      The  innominate  artery,    I  U)  5  cm.  |  I  J  to  '2  in. )  long,  has 

the  left  innominate  and  the  right  inferior  thyroid  veins  in  front;  the  right 
innominate  vein,  pneumogastne  nerve, pleura, and  lung  (<»  (he  right;  the 

trachea    behind    and    to  the  left,  and    the   left   carotid    artery  lo  die  left. 

These  tnosl  important  relations, and  die  occasional  Mi)  per  cent.)  origin 

from  it  of  the  thyroidea   ima  artery,  are  of  importance  in  the  diagnosis 

of  aneurysm  oi  this  artery  from  the  pressure  symptoms,  and  in  its  ligation 
for  aneurysm  of  it s  branches,  several  successful  cases  of  which  are  now 

1  For  the  above  variation!  iee  Henle'i  Anatomy,  1886,  vol,  iii.  |>|>.  203  el  wq.,  or 
.■He.  '!<•  criptive  ftnatom) 


260  THE  THORAX 

on  record.  The  chief  pressure  symptoms  are  weakness  or  absence  of  the 
radial  or  carotid  pulse;  cyanosis  and  edema  of  the  arm,  neck,  and  face, 
especially  of  the  right  side;  cough  and  hoarseness  (recurrent  laryngeal); 
dilatation  or  contraction  of  the  right  pupil  (sympathetic  nerve) ;  hiccough 
(phrenic  nerve);  dyspnea  and  dysphagia.  The  dangers  of  the  opera- 
tion itself  lie  in  the  important  structures  in  relation  with  it  and  in  the 
difficulty  of  an  adequate  exposure,  which  may  be  facilitated  by  osteo- 
plastic resection  of  the  manubrium  (Bardenheuer),  or  better  by  a  longi- 
tudinal median  section  of  the  sternum,  or  its  upper  half,  and  the  lateral 
retraction  of  the  divided  edges,  which  exposes  the  mediastinum  and  its 
contents.  The  simultaneous  ligation  of  the  right  common  carotid  and 
vertebral  lessens  the  risk  of  secondary  hemorrhage  distal  to  the  ligature. 

The  pulmonary  artery,  in  its  course  from  the  third  left  to  the  upper 
border  of  the  second  left  chondrosternal  junction,  projects  more  or  less 
beyond  the  left  border  of  the  sternum  in  the  second  space,  where  it  is 
exposed  to  injury.  Similarly  on  the  right  side  the  superior  vena  cava, 
from  its  origin  behind  the  sternal  end  of  the  first  costal  cartilage  to  its 
termination  behind  that  of  the  third  cartilage,  lies  just  to  the  right  of  the 
sternum  and  ascending  aorta,  and  is  exposed  to  injury  in  the  mesial  ends 
of  the  first  and  second  spaces.  The  left  innominate  vein  crosses  trans- 
versely behind  the  manubrium,  just  above  the  aortic  arch  and  just  below 
the  episternal  notch,  and  in  children  and  in  cases  of  great  venous  conges- 
tion or  of  high  position  of  the  aortic  arch  it  may  project  above  the  sternum, 
so  as  to  be  exposed  to  injury  in  a  low  tracheotomy  or  in  some  thyroid- 
ectomies. The  azygos  veins  are  of  practical  importance  on  account  of  the 
free  collateral  circulation  they  afford  between  the  inferior  and  superior 
cavse,  in  case  of  obstruction  of  the  former.  This  is  due  to  their  connection 
with  the  lumbar,  iliolumbar,  common  iliac,  and  renal  veins. 

The  great,  small,  and  least  splanchnic  nerves,  derived  from  the  fifth  to  the 
ninth,  the  tenth  to  the  eleventh,  and  the  twelfth  thoracic  sympathetic  ganglia 
respectively,  are  connected  with  the  correspondingly  numbered  thoracic 
nerves,  which  also  supply  the  abdominal  parietes.  Thus  the  same  seg- 
ments of  the  cord  supply  the  abdominal  viscera  and  the  skin  and  muscles 
covering  them.  As  the  splanchnic  nerves  pass  to  the  solar,  renal,  and 
other  plexuses  which  supply  the  abdominal  viscera,  they  account  for 
the  reflexes  between  the  abdominal  viscera  and  the  parietes  (see  p.  281), 
and  for  the  pain  in  some  diseases  of  the  liver  and  stomach,  in  the  region 
between  and  over  the  scapulae,  supplied  by  the  dorsal  branches  of  the 
thoracic  nerves  which  are  connected  with  the  splanchnics.  Pressure  of 
thoracic  tumors  or  aneurysms  upon  the  sympathetic  may  cause  dilatation  of 
the  pupil  of  that  side,  from  irritation  of  its  ciliospinal  fibers,  or  contraction 
of  the  pupil,  from  their  paralysis.  As  these  fibers  leave  the  cord  by  the 
first  thoracic  and  eighth  cervical  nerve  roots,  the  pressure  must  be 
exerted  at  the  upper  end  of  the  thorax  to  produce  these  pupillary  symptoms. 
As  some  filaments  of  the  right  phrenic  nerve  pass  to  the  solar  plexus  and 
the  liver,  the  pain  over  the  tip  of  the  right  shoulder  in  liver  disease  may  be 
explained  as  a  reflex  in  the  supra-acromial  filaments  from  the  third, 
fourth,  and  fifth  cervical  nerves,  from  which  the  phrenic  is  derived. 


PLATE  XXVI 


FIG.  93 


THORACIC 
DUCT 


VERTEBRAL 
VEIN 


BRACHIAL 
PLEXUS 


SUPERFIC.    CER- 
VICAL   VEIN 
SUBCLAV.    LYMFM 
-^       TRUNK 
SUBCLAV.   ARTERY 


Topography  of  the  Thoracic  Duct  in  the  Neck.     (Zuckerkandl.i 


THE   THORACIC  DUCT  261 


THE  THORACIC  DUCT. 


This  is  about  45  cm.  (18  in.)  Ioihj  from  its  commencement  in  the  abdo- 
men in  the  receptaculum  chyli,  opposite  the  second  (or  first)  lumbar 
vertebra,  to  its  termination  in  the  neck,  in  the  posterior  part  of  the  angle 
of  union  of  the  subclavian  and  internal  jugular  veins.  It  is  mostly 
contained  within  the  thorax.  Here,  after  passing  through  the  aortic 
opening  of  the  diaphragm  behind  the  aorta,  it  lies  between  the  latter  and 
the  vena  azygos  major,  in  the  posterior  mediastinum,  up  to  the  level  of  the 
fifth  thoracic  vertebra,  where  it  inclines  to  the  left  behind  the  esophagus, 
the  aortic  arch,  and  the  left  common  carotid  artery.  Thence  in  the 
superior  mediastinum  it  lies  between  the  esophagus  and  the  left  pleura, 
behind  the  left  subclavian  artery,  and  in  front  of  the  vertebral  artery. 
After  ascending  through  the  superior  thoracic  aperture  into  the  left  side 
of  the  neck  as  high  as  the  seventh  cervical  vertebra  it  arches  outward, 
forward,  and  downward  over  the  apex  of  the  pleura,  in  front  of  the  sub- 
clavian artery,  the  scalenus  anticus  muscle,  and  the  vertebral  vein,  and 
behind  the  left  internal  jugular  vein  and  carotid  artery,  becoming  exter- 
nal to  the  latter  (Fig.  93). 

The  highest  point  of  the  arch  of  the  thoracic  duct  normally  reaches  the 
level  of  the  transverse  process  of  the  sixth  cervical  vertebra.  Although 
in  the  thoracic  cavity  it  may  be  pressed  upon  by  tumors  and  aneurysms, 
and  its  rupture  is  reported  by  Krabbel  in  a  case  of  fracture  of  the  ninth 
thoracic  vertebra,  followed  by  a  chylous  effusion  of  more  than  a  gallon 
in  the  right  pleural  cavity,  it  is  /'//  the  neck  that  its  surgical  interest  lies. 
Here  it  has  been  /rounded  by  stab  and  bullet  wounds  and  in  extensive 
operations  for  tumors  or  tuberculous  glands  of  the  neck.  The  near 
neighborhood  of  many  vital  parts  would  render  rapidly  fatal  most  injuries 
of  the  duct,  unless  received  during  a  surgical  operation.  Under  normal 
anatomical  conditions  operative  injury  is  \ry\  unlikely,  as  the  duct  rises 
little  if  any  above  the  level  of  junction  of  the  two  great  veins;  but  it  not 

infrequently  rises  higher,  and  has  been  found  as  high  as  -V,  cm.  cj\  in.) 
above  the  sternum  (Dietrich).     When  injured  it  has  been  successfully 

BUtured  in  a  feu  cases,  and  in  others  its  leakage  has  been  checked  by 
clamps  or  packing. 

( Obstruction  of  the  duet  in  man  is  not  followed  by  constant  nor  always 
by  marked  symptoms,  for  the  lymphatics  .ire  continuous  with  the 
interstices  of  the  tissues  and  communicate  with  other  veins,  like  the 

azygOS  vein-  and  -mall  veins  in  the  groin  Leaf  .  hence  a  collateral  cir- 
culation may  be  established.  Chylou  a  cites  or  pleural  effusion  may  be 
due  to  obstruction  with  transudation  or  to  wound  or  rupture  of  the  duel 
or  if -,  linger  tributaries. 

■h/deroiiou  has  occurred  without  producing  any  marked  symptoms, 
though  experimental  ligation  in  dogs  has  been  followed  by  rupture  of  the 
receptaculum  chyli  or  other  fatal  lesions.  A  double  perfect  mlee  nt  iis 
entrance  into   the  vein    guard     against   regurgitation  of  lymph  or  tin 

entrance  of  blood.      It    may  enter  the   \<  in     ;i     ;i   delta.      Il    netiees  the 


262 


THE  THORAX 


lymph  and  chyle  from  all  parts  of  the  body  except  the  right  upper  extrem- 
ity, the  right  side  of  the  chest,  head,  and  neck,  and  the  convex  surface  of 
the  liver,  which  is  returned  by  the  right  lymphatic  duct  to  a  corresponding 
point  of  the  veins  on  the  right  side.    Its  injury  is  of  less  moment. 


Fig.  94 


COMMENCE- 
MENT 


FIRS. 
LATERAL- 
CURVE 


IMPRESSION 
OF    LEFT 
BRONCHUS 

SECOND  LAT- 
ERAL CURVE 


THE  ESOPHAGUS. 

Like  the  thoracic  duct,  the  esophagus  is  contained  partly  in  the  neck 
and  abdomen,  but  mostly  in  the  thoracic  cavity,  in  the  superior  and 

posterior  mediastina.  The  level  of 
the  commencement  of  the  esophagus, 
as  the  continuation  of  the  pharynx, 
depends,  like  that  of  the  trachea, 
on  the  position  of  the  head  and 
neck  and  varies  from  the  fifth  to  the 
sixth  or  seventh  cervical  vertebra. 
In  a  position  midway  between 
flexion  and  extension  of  the  neck  its 
upper  end,  behind  the  lower  border 
of  the  cricoid  cartilage,  is  opposite 
the  sixth  cervical  vertebra.  Its  lower 
end  passes  through  the  diaphragm, 
opposite  the  tenth  thoracic  vertebra, 
to  end  in  the  stomach,  opposite  the 
eleventh  vertebra.  Its  length  averages 
23  to  25  cm.  (9£  to  10  in.),  which 
with  the  distance  of  its  upper  end  from 
the  upper  incisor  teeth,  15  cm.  (6  in.), 
makes  the  average  distance  from  the 
latter  to  the  stomach  38.5  to  40  cm. 
(15-J-  to  16  in.) — 17  cm.  in  the  new- 
born (Mouton).  The  length  of  the 
cervical  portion,  i.  e.,  above  the 
episternal  notch  or  the  second  thora- 
cic intervertebral  disk,  averages  5  to 
7  cm.  (2  to  2f  in.)  and  ranges  be- 
tween 4.5  and  8.5  cm.  (Tillaux),  vary- 
ing with  the  length  and  position  of 
the  neck. 

Its  direction  (Fig.  91)  is  not  straight. 
It  inclines  to  the  left  in  the  neck  but 
is  pressed  back  to  the  median  line  by 
the  left  end  of  the  aortic  arch,  oppo- 
site   the    fourth     thoracic    vertebra. 
Below  this  it  again    curves  slightly 
to  the  left,  so  that  its  diaphragmatic  orifice  is  normally  somewhat   to  the 
left  of  the  median  line  and  to  the  left  and  in  front  of  the  aorta.    In  the 
sagittal  plane  it  follows  the  curved  line  of  the  vertebrae  to  the  fourth 


K 


Plaster  cast  of  esophagus,  showing  its 
curves  and  diameters.     (Mouton.) 


THE  ESOPHAGUS  263 

thoracic  vertebra,  below  which  it  gradually  leaves  the  vertebrae  and 
passes  more  vertically  to  its  diaphragmatic  orifice.  None  of  its  curves 
are  of  sufficient  extent  or  degree  to  interfere  with  the  passage  of  bougies 
or  straight  instruments. 

The  Lumen. — The  lumen  of  the  esophagus,  except  during  the  act  of 
swallowing  or  vomiting,  is  always  closed  in  the  cervical  portion,  some- 
times closed  and  sometimes  open  in  the  thoracic  portion,  according  as 
the  stomach  is  full  or  empty  of  gas  or  fluid.  The  caliber  of  the  esophagus, 
which  is  the  narrowest  section  of  the  alimentary  canal,  varies  and  presents 
three  constricted  parts,  one  at  its  commencement,  another  7  to  10  cm. 
(2f  to  4  in.)  below,  and  the  third  at  its  passage  through  the  diaphragm, 
22  cm.  (9  in.)  below.  The  latter  is  not  a  narrowing  of  the  tube  itself,  but 
is  due  to  the  fibers  of  the  diaphragm  which  surround  it  and  form  a  kind 
of  sphincter  for  it.  The  lowest  constriction  is  the  narroicest,  measuring 
12  mm.  in  diameter  as  compared  to  14  mm.  for  the  upper  two,  but  it  is 
more  distensible,  allowing  of  rapid  dilatation  to  22  mm.,  the  other  two  to 
18  or  19  mm. 

It  follows  that  in  an  adult's  esophagus  a  bougie  14  mm.  in  diameter 
should  pass  easily,  otherwise  there  is  a  stenosis,  and  that  in  dilating 
the  esophagus  an  instrument  of  18  mm.  diameter  should  be  the  limit. 
In  the  newborn  the  caliber  of  the  esophagus  is  4  mm.  In  passing  a  bougie, 
stomach  tube,  etc.,  the  patient's  head  is  thrown  back,  to  straighten  the 
curve  made  by  the  roof  of  the  mouth  and  the  pharynx,  the  tongue  and 
epiglottis  are  pressed  forward  by  the  finger,  and  the  point  of  the  instru- 
ment is  guided  to  the  posterior  pharyngeal  wall,  a  little  to  the  left,  and 
along  it  down  to  the  upper  end  of  the  esophagus.  On  account  of  a 
spasmodic  muscular  contraction  the  introduction  of  a  bougie  may  be 
hindered  at  the  upper  end  of  the  esophagus,  and  lower  down  it  may  be 
suddenly  held  in  the  same  way.  During  the  muscular  spasm  the  sound 
should  be  left  at  rest,  as  the  attempt  to  force  it  increases  the  spasm,  but 
the  latter  will  relax  if  the  patient  makes  the  movements  of  swallowing. 
Owing  to  the  firm  relations  in  front  of  and  behind  the  esophagus, 
/.  e.,  trachea  and  vertebrae,  it  is  less  distensible  in  these  directions  than 
laterally,  as  seen  in  sword  swallowing.  Accordingly  some  bougies  are 
made  flattened. 

Any  foreign  body  which  will  pass  the  upper  two  narrow  points  will 
probably  pa^s  the  lower  one.  Foreign  bodies  are,  therefore,  most  likely 
to  lie  arrested  at  the  upper  end  of  the  esophagus,  or  the  lower  end  of  the 
pharynx,  where  the  predominance  of  striped  muscle  tissue  in  the  walls 
often  allows  of  their  being  returned  to  the  mouth  by  a  spasmodic  mus- 
cular action.  If  this  fails,  they  may  be  removed  by  some  form  of  esophagus 
forceps,  a  may  also  those  bodies  arrest. •<!  at  the  sn'oml  inirnnr  point, 
which  begins  '■'>■'>  cm.  and  is  narrowest  7  em.  below.  If  the  forceps  or 
COin-catcher  fails  t"    remove  a  body  arrested  at   the  second  constriction, 

two  alternatives  present   themselves     pushing  it  down  to  the  stomach 
or  removing  it  by  an  external  esophagostomy. 
Strictures.     Stricturesof  the  esophagus, both  malignant  and  cicatricial, 
mo  i  likely  f<>  !"•  found  at  one  of  the  constricted  points.    The  oica- 


264  THE  THORAX 

tricial  variety  occurs  most  frequently  at  the  narrow  points  because  the 
corrosive  fluid  swallowed  takes  slightly  longer  in  passing  these  points,  and 
hence  acts  more  intensively  on  the  esophageal  wall,  causing  deeper 
ulceration  and  greater  subsequent  contraction.  Cancerous  stricture  is 
most  common  at  the  upper  or  lower  ends,  and  in  the  latter  case  the 
symptoms  are  not  infrequently  referred  to  the  upper  end. 

The  lymphatics  enter  the  mediastinal  and  the  deep  cervical  lymph  nodes 
so  that  if  cancer  of  the  esophagus  is  suspected  we  should  examine  the 
nodes  of  the  carotid  chain  at  the  root  of  the  neck. 

Relations. — The  relations  of  the  esophagus  are  especially  important  at 
the  narrow  'points,  where  lesions  are  likely  to  occur,  and  in  the  neck,  where 
esophagotomy  is  done  and  where  other  operations  and  injuries  may 
concern  it.  The  second  constriction  is  just  above  or  behind  the  aortic 
arch  and  the  left  bronchus,  and  foreign  bodies  arrested  here  have  ulcerated 
through  into  the  aorta,  causing  immediate  and  fatal  hemorrhage.  Thus, 
a  five-franc  coin  (Musee  Dupuytren),  a  fishbone  {Lancet,  1871),  etc., 
have  been  reported  ulcerating  into  the  aorta,  and  a  piece  of  bone  impacted 
in  the  esophagus  has  been  reported  (Ogle,  in  Path.  Soc.  Trans.,  vol.  iv), 
ulcerating  into  an  intervertebral  disk  and  setting  up  a  fatal  disease  of  the 
cord.  Aneurysm  of  the  aortic  arch  or  descending  aorta  may  press  upon  the 
esophagus  and  simulate  stricture  of  its  lumen.  A  bougie  passed  under 
such  conditions  may  penetrate  the  sac  and  bring  on  a  sudden  fatal 
bleeding.  Similarly  an  impacted  body  or  an  epithelioma  has  ulcerated 
into  the  lower  end  of  the  trachea,  the  left  bronchus  or  the  right  pulmonary 
artery,  which  also  lies  in  front  of  the  esophagus.  An  instrument  passed 
in  case  of  a  carcinomatous  stricture  of  the  esophagus  may  readily  pierce 
the  softened  wall  of  the  tube  and  penetrate  the  trachea  or  left  bronchus, 
setting  up  a  septic  pneumonia,  or  it  may  wound  the  aorta,  pericardium, 
pleura,  etc.,  with  a  fatal  result.  The  contiguity  of  the  esophagus  with 
the  membranous  wall  of  the  trachea  and  with  the  left  bronchus  explains 
the  effect  of  foreign  bodies  in  the  one  producing  symptoms  of  obstruction 
referable  to  the  other,  so  that  tracheotomy  has  been  done  for  a  foreign 
body  in  the  esophagus.  Of  course,  foreign  bodies,  especially  sharp  or 
irregular  ones,  may  become  arrested  elsewhere  than  at  the  narrowest 
points. 

The  aorta  winds  spirally  around  the  esophagus,  being  in  front  above, 
then  to  the  left,  then  behind,  and  finally  behind  and  to  the  right.  Below 
the  aortic  arch  the  esophagus  is  just  behind  the  bronchial  glands,  the 
pericardium  and  the  left  auricle,  so  that  in  enlargement  of  the  heart 
or  distention  of  the  pericardium  with  fluid  the  patient  may  be  unable 
to  swallow  with  comfort  in  the  supine  position.  The  esophagus  lies 
between  the  two  pleural  sacs,  but  in  more  direct  contact  with  the  left 
above  and  the  right  below.  Hence  carcinoma  of  the  esophagus  is  said 
to  extend  to  the  right  lung  and  pleura  more  often  than  to  the  left,  though  I 
have  observed  it  on  the  left  side.  The  thoracic  duct  is  to  the  right  below, 
to  the  left  above,  and  crosses  behind  it  about  the  fourth  or  fifth  thoracic 
vertebra.  Loose  cellular  tissue,  continuous  with  that  behind  the  pharynx, 
connects  the  esophagus  with  the  prevertebral  fascia,  etc.,  and  along  this 


PLATE  XXVII 


L.     PHR 
PECT 


RT.     PHRENIC   N. 


L      AURICLE 


RT.    PULMON    V. 


Transverse  Horizontal  Section  of  the  Body  at  the  Level  of  the 
Eighth  Thoracic  Vertebra.     (Joessel.) 


THE  ESOPHAGUS  265 

a  retropharyngeal  abscess  or  a  deep  abscess  of  the  neck  may  descend 
into  the  mediastinum  and  press  upon  the  esophagus. 

In  the  neck  its  relations  are  of  importance,  especially  on  the  left  side, 
on  which  external  esophagotomy  is  performed  as  the  esophagus  inclines 
to  the  left.  In  this  operation  the  left  recurrent  laryngeal  nerve,  the 
inferior  thyroid  artery,  and  the  left  lobe  of  the  thyroid  gland,  which  lie 
in  front  of  the  left  side  of  the  esophagus,  must  be  carefully  avoided. 
After  incising  along  the  anterior  border  of  the  left  sternomastoid,  from 
the  thyroid  cartilage  downward,  this  muscle  and  the  carotid  sheath  are 
retracted  outward,  the  other  structures  inward.  The  recognition  of  the 
esophagus  is  made  easier  by  a  bougie  passed  into  it  through  the  mouth. 
( )n  the  right  side  the  carotid  sheath  is  farther  removed  from  the  esophagi  is, 
and  the  recurrent  laryngeal  nerve  runs  more  along  its  lateral  border. 
The  modern  operation  of  gastrostomy  gives  good  results,  and  is  far 
preferable  to  esophagostomy.  The  thoracic  portion  of  the  esophagus 
may  be  operated  on  through  an  opening  in  the  anterior  or  posterior 
part  of  the  thorax.  The  collapse  of  the  lung  is  prevented  by  the  use  of 
increased  (positive)  pressure  in  the  lungs  or  by  operating  in  a  compart- 
ment in  which  the  pressure  is  diminished  (negative  pressure),  as  in 
Sauerbruch's  chamber.  In  cicatricial  strictures  there  is  a  pouch-like 
dilatation  of  the  esophagus  above  the  stricture,  the  opening  of  which  is 
usually  eccentric,  so  as  to  prevent  the  passage  of  bougies  from  above. 
Hence  the  retrograde  dilatation  through  an  opening  in  the  stomach  is 
the  best  method.  A  thread  swallowed  will  readily  pass  even  the  narrow 
('(•centric  strictures,  and  the  lower  end  may  be  washed  out  through  the 
<)])(■! ling  in  the  stomach.  Foreign  bodies  impacted  at  the  lower  end  may 
be  removed  by  gastrotomy  (Richardson). 

Congenitally  the  esophagus  may  be  deficient  in  part  and  open  into 
the  trachea  below  or,  more  rarely,  above,  or  it  may  also  be  the  seat  of  a 
tracheo-esophageal  fistula,  an  annular  stricture,  a  dilatation,  or  a  doubling 
or  division  of  the  tube.  The  esophagus  may  be  much  dilated  above  any 
stricture,  but  especially  above  the  spastic  condition  known  as  cardio- 
spasm, in  which  the  tube  above  the  eardia  may  contain  a  liter  or  more. 
True  diverticula,  both  pulsion  and  traction  diverticula,  are  acquired.  The 
former  are  due  to  a  hernia  of  the  mucosa  through  the  inferior  constrictor 
of  the  pharynx  on  the  posterior  wall  at  the  upper  end  of  the  esophagus  or 
die  lower  end  of  the  pharynx,  the  latter  arc  due  to  the  contraction  of  scar 
tissue  connecting  the  esophagus  with  surrounding  parts  (/.  r.,  bronchial 
glands,  etc.),  and  arc  most  often  on  its  anterior  wall  just  below  the 
bifurcation  of   the    trachea. 


CHAPTER    IV. 

THE   ABDOMEN. 

Shape. — In  general  the  abdomen  is  barrel-shaped,  flattened  from 
before  backward,  bulging  in  the  centre  and  wider  below  than  above.  In 
the  adult  female  the  larger  circumference  below  than  above  Is  due  to 
the  size  of  the  pelvis,  largely  due  to  the  accumulation  of  fat,  and  is  still 
more  marked  when  the  upper  part  has  been  compressed  by  corsets. 
In  childhood,  owing  to  the  incomplete  development  of  the  pelvis,  the 
abdomen  is  larger  above  than  below,  especially  in  its  transverse  diameter. 
The  height  of  the  abdomen  in  the  female  is  greater  than  in  the  male,  owing 
to  the  greater  size  of  the  lumbar  vertebra?.  The  long  axis  of  the  abdominal 
cavitv  is  not  vertical  but  oblique  from  above  downward  and  to  the  right, 
owing  to  the  greater  height  of  the  diaphragm  on  the  right  side.  The 
intra-abdominal  pressure  acting  most  strongly  in  this  line  is  said  to  account 
for  the  greater  frequency  of  hernia  on  the  right  than  on  the  left  side. 

In  fat  subjects  the  abdomen  protrudes  to  a  varying  degree  in  front, 
owing  to  the  deposit  of  fat  among  the  abdominal  viscera  and  the  peri- 
toneal folds  and  to  the  large  amount  of  subcutaneous  adipose  tissue.  In 
rime,  the  protrusion  is  carried  downward  by  gravity,  aided  by  the  laxity 
of  the  walls  and  the  abdomen  becomes  pendulous. 

I  infants  the  abdomen  protrudes  in  front,  owing  to  the  relatively  large 
size  of  the  liver  and  the  small  size  of  the  pelvis,  which  crowds  the  pelvic 
viscera  bladder,  rectum,  etc.  i  partly  up  into  the  abdomen.  The  latter 
condition,  apart  from  the  amount  of  fat,  accounts  for  the  protrusion  of 
the  abdomen  in  children  until  the  pelvis  enlarges  at  the  approach  of 
puberty. 

Certain  physiological  and  pathological  conditions  cause  a  general  or 
local  protrusion  of  the  abdomen,  such  as  pregnane  ascites,  distention 
of  the  hollow  viscera  (tympanites  i,  enlargement  of  the  solid  viscera, 
and  rumors  or  cysts  of  the  abdominal  contents  or  walls.  After  long- 
continued  distention,  an  undue  amount  of  prominence  or  pendulousness 
often  remains. 

In  cases  of  great  emaciation  from  starvation  or  wasting  disease,  the 
contour  of  the  abdomen  is  much  depressed  in  front  and  especially  just 
beneath  the  costal  margin  where  the  slight  normal  median  depression, 
known  as  the  "pit  of  the  stomach"  (or  scrobiculus  cordis),  may  become 
so  marked  that,  in  the  recumbent  position,  the  wall  sinks  away  almost 
vertically  from  the  costal  margin  and  the  prominence  of  the  vertebrae 
is  noticeable.  In  tuberculous  meningitis  and  lead  colic  the  abdomen 
shows  a  "boat-shaped"  depression  in  front,  owing  to  the  contraction  of 
the  empty  bowels. 


THE  ABDOMEN  2(17 

Boundaries. — The  abdomen,  including  the  pelvis,  is  bounded  above 
by  the  diaphragm,  which  separates  it  from  the  thorax,  below  by  the 
pelvic  floor.  A  plane  drawn  through  the  base  of  the  ensiform  carti- 
lage in  front  and  the  tenth  thoracic  spine  behind  suggests  the  upper 
limit  of  the  cavity,  which,  however,  ascends  even  higher  than  this  into 
the  vault  of  the  diaphragm. 

The  actual  upper  limit  of  the  abdomen,  extending  up  as  it  does  under 
cover  of  the  lower  ribs  and  costal  cartilages,  is  higher  than  the  apparent 
limit,  i.  e.,  the  costal  margin. 

It  is  bounded  behind  by  the  lumbar  vertebra?,  sacrum,  lower  two  or 
three  ribs,  diaphragm,  lumbar  muscles,  and  the  posterior  portions  of  the 
ilia;  in  front,  by  the  costal  cartilages,  forming  the  costal  margin,  the 
symphysis,  the  body  and  rami  of  the  pubis,  and  the  ventral  abdominal 
muscles;  laterally,  by  the  lower  ribs  and  diaphragm,  the  ilia  and  ischia, 
and  the  fleshy  portions  of  the  flat  abdominal  muscles. 

Except  for  operations  on  subdiaphragmatic  and  liver  abscesses  and 
wounds  through  the  diaphragm,  after  suture  of  the  diaphragm  to  the 
opening  in  the  costal  pleura,  no  operations  are  done  through  the  upper 
boundary  or  diaphragm.  Many  operations  are  performed  through  the 
perineum  and  the  pelvic  floor  on  the  rectum,  female  pelvic  organs,  and 
male  genito-urinary  organs.  Hahn's  operation  for  gastrostomy  is  done 
through  the  eighth  intercostal  space,  and  occasionally  the  iliac  fossa 
has  been  perforated  for  drainage  of  an  abscess.  Otherwise  abdominal 
operations  are  performed  through  the  soft  parts,  which  indicate  the 
apparent  limit  of  the  abdomen  and  form  an  hexagonal  area  bounded 
by  the  costal  cartilages  of  the  six  lower  ribs  and  by  the  twelfth  ribs 
above,  the  transverse  processes  of  the  lumbar  vertebras  behind,  and 
by  the   iliac  and   pubic  crests  and  Poupart's  ligaments  below. 

Superficial  Markings  and  Landmarks.— Bony  Points. — Superiorly 
the  emiform  cartilage  and  the  diverging  margins  of  the  costal  cartilages 
(bounding  the  infracostal  angle)  are  often  visible  and  always  palpable. 
Tne  tip  of  the  ensiform  cartilage  is  about  on  a  line  with  the  lower  pari  of 
the  tenth  thoracic  vertebra.  There  is  a  palpable  notch  on  the  costal  man/in 
between  the  tip  of  the  tenth  and  the  border  of  the  ninth  costal  cartilage, 
which  is  a  useful  landmark. 

The  tips  of  the  eleventh  and  twelfth  COStol  cartilages  lie  i'rvv  between 
the  abdominal  muscles.     They  can  be  readily  felt  except  in  fat  subjects, 

but  it  is  never  ^afe  to  rely  upon  palpation  alone  in  determining  the 
twelfth  rib   see  p.  315),  and  the  ribs  should  always  be  counted  from  above 

to  locate  the  twelfth  rib  in  lumbal' operations. 

As  the  spines  of  the  lumbar  vertebra  closely  correspond  with  the  level 

of  their  bodies,  sonic  of  the   relations  of  the   hitter  may  here  be  given 

according  to  Holden  and  Windle: 

First    lumbar    vertebra    and    spine:  pancreas,   pelvis   of    kidney,   with 

endings  of  renal  arteries.  Junction  of  first  and  second:  end  of  spinal 
cord.  Second:  duodenojejunal  junction;  opening  into  intestine  of 
ductus  communis  choledochus,  upper  end  of  root  of  mesentery,  com- 
mencement of  portal  vein,  superior  mesenteric  artery,  and  thoracic  duct. 


268  THE  ABDOMEN 

Third :  lower  border  of  kidney.  Junction  of  third  and  fourth :  umbilicus. 
Fourth:  highest  part  of  iliac  crest,  bifurcation  of  aorta.  Second  or 
third  sacral  vertebra:   limit  of  spinal  membranes. 

The  anterior  superior  iliac  spine  is  an  important  landmark  in  deter- 
mining the  length  of  the  lower  extremities  in  fractures  of  the  femur  and 
in  injuries  and  diseases  about  the  hip-joint.  On  a  line  between  it  and  the 
umbilicus,  about  5  to  6  cm.  (2  to  2\  in.)  from  the  iliac  spine  is  "  McBur- 
ney's  'point,"  commonly  the  point  of  greatest  tenderness  in  appendicitis. 
This  spine  is  at  the  outer  extremity  of  the  inguinal  fold  (due  to  Pou- 
part's  ligament),  where  in  thin  subjects  it  is  visible  as  a  prominence, 
in  fat  subjects  as  a  depression,  and  in  all  subjects  it  is  palpable.  It  lies 
at  or  below  the  level  of  the  top  of  the  promontory  of  the  sacrum,  in  the 
erect  position. 

Extending  outward  and  upward  from  this  spine  the  sinuous  iliac 
crest  may  be  felt  throughout,  except  mesially,  in  very  fat  subjects.  In 
muscular  subjects  it  lies  in  a  groove  {iliac  furrow)  below  the  fleshy  fibers 
of  the  external  oblique  muscle.  It  ends  mesially  in  the  posterior  superior 
iliac  spine,  often  difficult  to  feel,  but  indicated  by  a  slight  depression  on  a 
level  with  the  spinous  process  of  the  second  sacral  vertebra. 

The  pubic  spine  is  another  bony  landmark  of  special  importance  in  the 
anatomy  of  hernia,  lying  external  to  the  neck  of  an  inguinal  hernia  and 
internal  to  that  of  a  femoral.  It  lies  at  the  inner  end  of  the  inguinal 
furrow  and  of  Poupart's  ligament.  It  is  readily  palpable  except  in  fat 
subjects,  in  whom  it  may  be  found  by  following  up  the  adductor  longus 
tendon  and,  in  the  male,  by  invaginating  the  scrotum  and  thus  getting 
beneath  the  subcutaneous  fat.  It  lies  in  the  same  horizontal  plane  with 
the  upper  border  of  the  great  trochanter.  Between  it  and  the  symphysis 
pubis  the  pubic  crest  may  be  felt,  except  in  the  obese. 

Lines,  Muscles,  etc. — The  linea  alba  (see  also  p.  275),  corresponding 
to  the  fibrous  interval  between  the  two  recti  muscles,  is  marked  by  a 
slight  median  groove  (the  abdominal  furrow)  from  the  infrasternal 
depression  (pit  of  the  stomach),  below  the  ensiform  cartilage,  to  a  little 
below  the  umbilicus.  Below  this  it  is  only  visible  in  those  without 
much  subcutaneous  fat  when  the  recti  muscles  contract,  owing  to  their 
close  approximation,  and  the  concealment  of  their  lower  ends  by  a  small 
amount  of  fat. 

The  umbilicus  (see  also  p.  257)  lies  20  to  25  mm.  (f  to  1  in.)  above  the 
bifurcation  of  the  aorta,  about  on  a  line  connecting  the  highest  points  of 
the  iliac  crests  and  on  a  level  with  the  disk  between  the  third  and  fourth 
lumbar  vertebra?  and  the  lower  end  of  the  third  lumbar  spine.  Whereas, 
at  birth  it  lies  below  the  centre  of  the  body,  in  the  adult  it  is  above  this 
point,  which  lies  nearer  the  symphysis  pubis.  It  always  lies  below  the 
centre  of  the  linea  alba,  about  the  junction  of  its  upper  three-fifths  with 
the  lower  two-fifths,  and  it  is  displaced  downward  when  the  abdomen 
is  obese  or  pendulous. 

The  linea  semilunaris  (see  also  p.  274)  corresponds  to  the  outer  border 
of  each  rectus  muscle,  and  may  be  well  seen  when  that  muscle  is  in 
action,  as  a  slightly  curved  line  convex  laterally,  from  the  tip  of  the  ninth 


THE  ANTERIOR  ABDOMINAL   WALL  269 

costal  cartilage  to  the  pubic  spine.  This  border  extends  to  the  midpoint 
of  the  line  joining  the  umbilicus  and  the  anterior  superior  iliac  spine, 
except  in  a  protruding  abdomen.    It  lies,  on  the  average,  about  7.5  cm. 

(3  in.)  laterally  from  the  umbilicus,  and  above  that  level  the  line  is  indi- 
cated by  a  shallow  groove  which  ends  above  at  the  margin  of  the  thorax 
in  a  somewhat  triangular  infracostal  fossa. 

When  in  action  the  rectus  presents  three  slight  transverse  grooves 
extending  between  the  linese  alba  and  semilunaris  and  representing  the 
lineae  transversa  (see  also  p.  272).  One  is  about  the  level  of  the  tip  of  the 
ensiform  cartilage,  a  second  at  that  of  the  tip  of  the  tenth  rib,  or  midway 
between  the  first  and  the  third,  which  is  at  the  navel.  Occasionally  a 
fourth  occurs  below  the  navel,  in  the  outer  half  of  the  muscle. 

The  inguinal  furrow  corresponds  to  Poupart's  ligament,  and  is  an 
important  landmark  in  the  surgical  anatomy  of  hernia. 

Lateral  to  the  linea  semilunaris  the  upper  part  of  the  fleshy  portion 
of  the  external  oblique  is  seen  interdigitating  with  the  serratus  magnus 
in  a  zigzag  line  directed  obliquely  downward  and  backward.  Its  promi- 
nence above  the  iliac  crest  forms  the  iliac  furrow  which  corresponds  to 
the  crest. 

The  superficial  epigastric  vein  (see  also  p.  279)  is  often  visible  through 
the  skin,  especially  if  enlarged,  when  it  may  be  seen  to  communicate 
with  another  vein  (thoracico-epigastric)  which  joins  the  axillary  vein, 
as  well  as  with  the  superior  epigastric  branch  of  the  internal  mammary 
rein. 

THE  ANTERIOR  ABDOMINAL   WALL. 

Tin-  lateral  hinits  may  be  taken  to  be  the  lateral  border  of  the  external 
oblique  muscle,  which  alone  of  the  flat  abdominal  muscles  has  a  \'wr 
lateral  margin  between  the  thorax  and  the  iliac  crest  (see  p.  271).  The 
Soft  parts  may  be  Studied  by  layers  and  then  certain  important  areas 
considered  separately. 

The  Skin.  The  skin  is  thill  and  loosely  attached  to  the  tissues  beneath, 
except  around  the  umbilicus  and,  to  a  less  extent,  in  the  median  line. 
Below  the  umbilicus  the  linea  alba  IS  often  indicated  by  a  line  of  pig- 
mentation in  the  skin.  In  the  male  the  skin,  especially  above  the  pubis 
and  near  the  median  line,  is  often  beset  with  hairs.    The  numerous  hair 

follicles  may  make  it  difficult  to  make  the  skin  reasonably  aseptic.  The 
'■!<  wage  Inns  of  the  skin  are  in  general  parallel  with  the  course  of  the 
lower  intercostal  and  the  upper  lumbar  nerves.  When  the  skin  has  been 
greatly  stretched  from  abdominal  distention,  scar-like  silvery  streaks 
(stria  gravidarum)  appear,  especiall)  in  the  lower  part  where  the  dis- 
tention Is  usually  greatest.  They  are  due  to  atroph)  of  the  skin  from 
stretching,  but  are  not  evidence  of  pregnancy,  for  they  may  follow  any 
great  di  Mention. 
The  Superficial  Fascia.  The  superficial  fascia,  unlike  the  subcutaneous 
in  mo  i  regions,  con  i  I  of  two  layers,  which  are  most  distinct  in 
the  lower  half  of  the  alidomen.    Between  the  two  layers  at  the  groin  are 


270  THE  ABDOMEN 

the  superficial  bloodvessels.  Both  layers  are  continued  on  to  the  external 
genitals  and  the  perineum. 

The  Superficial  Layer. — The  superficial  layer  of  the  superficial  fascia 
contains  the  subcutaneous  fat,  the  deposit  of  which  is  greatest  toward  the 
middle  and  lower  part,  reaching  its  maximum  in  the  female  over  and 
about  the  pubis,  as  the  mons  veneris.  The  fatty  deposit  may  reach  such 
a  thickness  (15  cm.  [6  in.]  has  been  found)  as  to  make  examination  of  the 
abdominal  wall  or  contents  impossible,  and  even  to  contra-indicate 
operation.  The  thicker  the  layer,  the  longer  the  incision  required.  The 
fat  of  the  abdominal  wall  acts  as  a  non-conductor  to  prevent  changes  of 
temperature  affecting  the  viscera,  and  thus  serves  as  a  "cholera  band." 
The  comparative  thickness  of  the  belly  wall  in  different  subjects  depends 
upon  the  amount  of  this  fat  rather  than  upon  the  thickness  of  the  muscles. 

This  layer  is  continuous  with  the  superficial  fascia  on  all  sides.  In 
thin  subjects  the  fat  may  be  so  small  in  amount  that  not  only  are  the 
muscles  and  superficial  markings  very  clearly  seen,  but  intestinal  peri- 
stalsis ("peristaltic  wave")  may  be  felt  and  seen  and  visceral  tumors  may 
be  readily  outlined  through  the  thin  wall.  In  very  fat  subjects,  two  deep 
folds,  involving  the  skin  and  this  layer,  run  transversely  across  the  abdo- 
men, one  at  the  umbilicus,  concealing  it,  and  the  other  just  above  the 
pubis.  Where  the  latter  Crosses  the  median  line  the  trocar  should  be 
introduced  in  tapping  the  bladder.  These  folds  are  due  to  a  slight  absorp- 
tion of  fat,  due  to  the  pressure  of  the  creasing  of  the  skin  in  bending 
forward. 

The  Deep  Layer. — The  deep  layer  of  the  superficial  fascia  consists 
of  a  firm  membrane  containing  elastic  fibers.  It  is  firmly  attached  to  the 
deeper  parts  in  the  median  line  down  to  the  symphysis  and  to  the  fascia 
lata  just  below  Poupart's  ligament  and  along  the  iliac  crest.  Between  the 
symphysis  and  the  pubic  spines  it  is  not  attached  to  the  underlying  parts, 
but,  uniting  with  the  superficial  layer,  which  here  has  lost  its  fat,  it  passes 
down  to  become  continuous  with  the  dartos  of  the  scrotum  and  penis. 
Many  interesting  clinical  facts  depend  upon  this  arrangement.  Sub- 
cutaneous emphysema  due  to  injuries  of  the  chest,  lipomata,  blood  or 
pus  beneath  this  layer  are  arrested  at  the  median  line,  the  inguinal  fold, 
and  the  iliac  crest,  and  are  prevented  from  reaching  the  thigh  or  the  but- 
tock by  reason  of  its  firm  attachment  to  deeper  parts.  They  may,  how- 
ever, pass  down  into  the  scrotum  between  the  symphysis  and  the  pubic 
spines.  If  the  same  conditions  occur  superficial  to  this  layer,  they  may 
readily  extend  in  all  directions. 

Tillaux  describes  a  lipoma  beneath  the  deep  layer  in  the  inguinal 
region,  which  was  thought  to  be  an  inguinal  hernia,  but  was  shown 
not  to  be  by  reason  of  the  emptiness  of  the  inguinal  canal. 

In  like  manner  extravasated  urine,  pus  or  blood  in  the  scrotum  may 
ascend  onto  the  abdomen,  between  the  pubic  spines  and  the  symphysis, 
but  cannot  cross  the  median  line  or  descend  onto  the  thighs  without  first 
perforating  this  layer.  Between  the  two  layers  lie  the  superficial  vessels, 
hence  we  may  remember,  in  making  incisions,  that  the  fatty  layer  is 
free  from  large  bloodvessels. 


PLATE  XXVIII 


FIG.  96 


RECTUS 

ABDOMINAL 


LINEJE 

TRANSVERSA 
EXTERNAL 

OBLIQUE 
LINEA    ALBA 


NTERNAL 
OBLIQUE 


POUPART'S 
LIGAMENT 

INTERNAL 

ABDOMINAL 
RING 


Muscles,  Vessels,  and  Nerves  of  the  Anterior  Abdominal  Wall. 

CJoessel.) 


THE  ANTERIOR  ABDOMINAL  WALL  271 

Of  little  surgical  importance,  as  far  as  the  abdomen  is  concerned,  is 
a  thin  cellular  fascia  covering  the  external  oblique  muscle.  In  the 
inguinal  region  this  seems  to  be  continuous  with  the  intercolumnar  fibers 
and  to  be  continued  down  into  the  scrotum  as  the  external  spermatic 
fascia,  one  of  the  coverings  of  the  cord  or  of  an  inguinal  hernia. 

The  Muscular  Layers. — The  muscular  layers  present  vertically  directed 
fibers  mesially,  in  the  rectus  and  pyramidalis  muscles,  and  obliquely 
directed  fibers  laterally,  in  the  external  and  internal  oblique  and  trans- 
versals muscles.  The  strength  of  the  abdominal  walls  depends  chiefly 
upon  the  muscles.  It  should  be  remembered,  however,  that  these  muscles 
are  much  thinner,  in  most  cases,  than  one  would  be  led  to  suppose  from 
their  description  in  text-books. 

The  flat  fleshy  bellies  of  the  oblique  muscles  are  found  largely  at  the 
sides,  where  they  fill  in  the  interval  between  the  vertical  muscles  behind 
and  in  front,  except  for  a  narrow  strip  along  the  outer  border  of  the 
rectus,  where  their  aponeuroses  form  the  fibrous  semilunar  line,  and  a 
small  semilunar  area  beneath  the  conjoined  tendon. 

The  fleshy  portion  of  the  external  oblique  terminates  in  a  right  angle, 
readily  seen  in  muscular  subjects,  some  distance  from  the  border  of  the 
rectus.  It  lies  above  a  horizontal  line  drawn  from  a  point  on  the  iliac 
crest  2.5  to  5  cm.  (1  to  2  in.)  behind  the  anterior  superior  iliac  spine, 
and  external  to  a  vertical  line  from  the  lowest  point  of  the  ninth  rib. 
It  also  lies  somewhat  above  a  line  connecting  the  anterior  superior  iliac 
spine  with  the  umbilicus;  hence  only  the  upper  part  of  the  usual  oblique 
incisions  in  this  region  involves  the  fleshy  fibers  of  this  muscle.  It  is  the 
only  one  of  the  three  flat  muscles  in  question  which  has  a  free  posterior 
border,  between  its  attachment  to  the  last  rib  and  the  middle  of  the  iliac 
crest,  the  other  two  muscles  being  connected  posteriorly  with  the  lumbar 
fascia.  This  free  lateral  border  may  be  overlapped  throughout  by  the 
latissimus  dorsi,  or  a  triangular  interval  of  varying  size  may  be  left 
between  these  two  muscles  and  above  the  iliac  crest,  the  triangle  of  Petit, 
whose  floor  is  formed  by  the  internal  oblique.  This  is  a  point  of  least 
resistance  where  abscesses  may  point  or  a  rare  form  of  hernia  may  occur 
(lumbar  hernia). 

The  direction  of  the  muscular  and  aponeurotic  fibers  of  (he  external 
oblique  is  approximately  at  right  angles  to  the  line  connecting  (he  anterior 
superior  iliac  spine  and  the  umbilicus. 

The  fleshy  portion  of  the  internal  oblique  extends  beyond  that  of  the 
external  both  mesially  and  laterally,  especially  inferiorly  and  mesially. 

Th.-  lower  fibers,  blended  with  those  of  the  t raiisversalis  to  form  the 
Conjoined  tendon,  are  directed  downward  and  inward  and  arch  over  the 
inguinal  canal  to  be  inserted  into  the  inner  L'..".  cm.  (I  in.)  of  the  ilio- 
pectineal  line  and  the  pubic  spine  and  crest,  in  front  of  the  rectus.  This 
behind  the  external  abdominal  ring  and  covers  and  strengthens 
an   otherwise    \vc;ik    area    in    the    inguinal    region,    but    leaves    a    ii;iit<>\\ 

uncovered  space  between  its  lower  curved  margin  and  the  inner  half  of 
Poupart'a  ligamenl  (see  Inguinal  Region,  p.  290).  The  fleshy  libers  of 
tin-  internal  oblique  are  directed  in  :«  fan-shaped  manner,  but,  r\<-ryi 


272  THE  ABDOMEN 

those  forming  the  conjoined  tendon,  the  general  direction  is  upward  and 
inward,  crossing  those  of  the  external  oblique  nearly  at  a  right  angle, 
like  bars  of  lattice-work.  They  do  not  reach  above  a  horizontal  line 
drawn  below  the  tip  of  the  last  rib,  nor  in  front  of  a  line  drawn  upward 
and  a  little  outward  from  the  centre  of  Poupart's  ligament,  except  for 
the  conjoined  tendon. 

The  fleshy  fibers  of  the  trans versalis,  directed  for  the  most  part  trans- 
versely, present  mesially  a  concave  margin,  approaching  nearer  the 
middle  line  above  and  below.  The  upper  fibers  pass  beneath  the  rectus, 
and  therefore  underlie  the  semilunar  line  in  the  upper  part;  the  lower 
fibers  take  part  in  forming  the  conjoined  tendon,  but  arch  higher  above 
the  inguinal  canal  and  give  no  covering  to  the  cord  or  a  hernia,  as  does 
the  internal  oblique  by  means  of  the  cremaster  muscle. 

These  three  flat  abdominal  muscles  are  separated  from  one  another 
by  a  certain  amount  of  loose  connective  tissue,  which  favors  the  spread 
of  inflammation  from  a  wound  or  of  a  mural  abscess  from  spinal  caries, 
etc.  Such  abscesses  will  be  limited  by  the  semilunar  line  in  front,  the 
erector  spinse  behind,  Poupart's  ligament  and  the  iliac  crest  below, 
and  the  costal  arch  above,  and  usually  work  down  to  the  iliac  crest,  the 
inguinal  fold,  or  along  the  inguinal  canal  into  the  scrotum  or  labia. 

Between  the  internal  oblique  and  transversalis  muscles  run  the  main 
trunks  of  the  lower  thoracic  and  upper  lumbar  nerves  that  supply  the 
muscles  and  skin  of  the  abdomen. 

The  different  direction  with  the  resulting  crossing  of  the  fibers  of  the 
oblique  and  transversalis  muscles  has  the  following  practical  results: 
(1)  It  strengthens  the  abdominal  wall  and  greatly  reduces  the  possi- 
bility of  a  hernia  between  the  separated  fibers  of  the  muscles.  (2)  It 
permits  contraction  of  the  abdominal  wall  in  every  direction,  and  thus 
(3)  increases  the  amount  of  abdominal  pressure  for  the  expulsion  of 
urine,  feces,  and  the  fetus.  (4)  It  produces  greater  approximation  in 
the  movements  of  the  movable  bony  boundaries  of  the  abdomen.  (5)  It 
affords  a  landmark  or  an  index  as  to  the  depth  of  an  incision  in  operations. 

Before  studying  the  aponeuroses,  or  tendons,  of  the  above  muscles  it 
is  convenient  to  consider  the  vertical  muscles,  the  rectus,  and  pyriformis. 

The  two  recti  run  longitudinally  the  entire  length  of  the  abdominal 
parietes  on  either  side  of  the  median  line.  They  are  much  narrower 
below  than  above,  and  in  the  upper  two-thirds  are  said  to  be  about 
as  broad  as  the  hand,  at  the  heads  of  the  metacarpal  bones.  The 
longitudinal  fibers  are  interrupted  by  fibrous  intersections  at  the  lineae 
transversa,  so  that  they  do  not  run  the  entire  length  of  the  muscle. 
The  linese  transversa  represent  the  septa  which  divide  the  muscles  of  the 
abdomen  at  intervals  in  the  lower  vertebrates  and  the  abdominal  ribs 
of  the  crocodile.  The  latter  analogy  is  indicated  by  the  relation  of  some 
of  the  lower  thoracic  nerves  to  the  intersections,  similar  to  that  of  these 
nerves  to  the  ribs.  The  intersections  serve  the  important  function  of 
holding  together  the  fibers  of  the  muscle  and  preventing  the  formation 
of  ventral  hernia  in  cases  of  great  abdominal  distention  from  pregnancy, 
etc.,  but  they  do  not  offer  serious  resistance  to  the  longitudinal  separation 


THE  ANTERIOR  ABDOMINAL    WALL  273 

of  the  fibers  in  a  vertical  incision  through  the  rectus.  They  prevent  the 
extensive  retraction,  after  division  of  the  muscle,  which  would  result  if 
the  fibers  were  uninterrupted.  Resembling  as  they  do  transverse  scars, 
they  indicate  that  transverse  incisions  of  this  muscle,  if  healed  by  a  proper 
cicatrix,  only  increase  the  number  of  such  transverse  intersections  which 
nature  provides  to  strengthen  the  muscle,  and  therefore  can  do  no  harm. 
These  fibrous  intersections  are  adherent  to  the  front  but  not  to  the  back 
of  the  sheath  of  the  rectus;  hence  suppuration  in  the  rectus  may  be 
limited  to  the  interval  between  two  transverse  intersections,  or  below 
the  lower  one,  though  it  may  extend  along  its  entire  dorsal  surface 
where  the  intersections  are  not  connected  with  the  sheath. 

By  means  of  this  connection  of  the  intersections  with  the  sheath, 
the  action  of  the  rectus  may  affect  the  latter  and  the  aponeuroses  of  which 
it  is  formed,  thus  diffusing  its  action.  They  allow  part  of  the  muscle  to 
act  at  a  time,  as,  for  example,  the  lower  part  in  micturition. 

Similarly  the  rectus  may  be  the  seat  of  a  form  of  phantom  tumor  in 
hysterical  subjects,  due  to  the  contraction  of  a  part  of  the  muscle,  usually 
to  a  segment  between  two  intersections.  The  irregular  contraction  of 
other  abdominal  muscles  may  also  cause  a  phantom  tumor.  When 
associated  with  distention  of  the  bowels  from  flatus  or  feces,  and  with 
abdominal  or  pelvic  symptoms,  such  tumors  may  mislead.  The  relaxa- 
tion of  the  contraction  from  an  anesthetic,  or  otherwise,  causes  the  tumor 
to  disappear.  They  are  said  to  be  more  common  in  the  left  rectus.  The 
position  of  the  intersections  has  already  been  given  (see  p.  2G9). 

The  fibers  of  the  rectus  are  in  rare  instances  torn  by  muscular  violence 
and  in  opisthotonos. 

Below  the  umbilicus  the  two  recti  are  so  close  together  that  it  is  scarcely 
possible  to  make  a  median  incision  without  exposing  the  mesial  fibers 
of  one  or  both. 

The  pyramidalis  muscles  lie  beneath  the  sheath  of  the  recti,  in  front  of 
the  latter  muscles  and  separated  from  them  by  a  layer  of  fibrous  tissue. 
They  are  inserted  into  the  linea  alba  one-third  to  one-half  the  distance 
between  the  symphysis  and  the  umbilicus,  and,  when  large,  may  entirely 
cover  the  median  line,  so  that  division  of  (heir  fleshy  libers  cannot  be 
avoided  in  a  median  incision.  They  may  be  absent  or  unusually  small 
on  one  or  both  sides. 

The  anterior  aponeuroses  of  the  oblique  and  transversalis  muscles  extend 
from  the  mesial  borders  of  the  fleshy  portion  of  these  muscles  to  the 

median  line,  where  they  unite  with  those  <>f  the  opposite  side  to  form  the 

linea  nlhu.  Tims  the  transversalis  muscles  of  the  two  sides  may  1><'  con- 
sidered a  double-bellied  muscle  with  an  intervening  tendon,  and  the 
same  may  be  -aid  of  th<-  external  oblique  <>n  one  side  with  the  internal 
oblique  of  the  opposite  side,  \'<>v  their  fibers  run  in  a  similar  direction. 
The  aponeurosis  of  the  external  oblique  is  widest  below,  thai  of  the  inter- 
nal oblique  above,  ;in«l  thai  of  the  f  ra  nsvers:dis  in  the  middle. 

The  Inguinal  or  Poupart's  ligament  is  formed  of  the  thickened  lower 
fibers  of  the  aponeurosis  of  the  external  oblique  which  extend  from  the 
anterior  superior  iliac    pine  t.,  the  pubic  spine.    It  can  be  felt  us  a  linn 

band. 

is 


274  THE  ABDOMEN 

Beneath  it  the  iliopsoas  muscle,  the  femoral  vessels,  the  anterior 
crural,  the  external  cutaneous,  and  the  crural  branch  of  the  genito- 
crural  nerves  pass  from  the  pelvis  into  the  thigh.  It  is  somewhat  infolded 
on  itself  so  as  to  form  a  kind  of  gutter,  the  concavity  of  which  is  directed 
upward  and  inward,  and  the  dorsal  margin  of  which  is  loosely  connected 
with  the  transversalis  fascia  and,  in  the  outer  part,  with  the  iliac  fascia 
also  (Fig.  97).  Upon  the  concavity  of  this  gutter  lie  the  structures 
which  pass  out  at  the  external  abdominal  ring. 

Inferiorly  it  is  firmly  connected  with  the  fascia  lata  of  the  thigh,  which, 
in  the  extended  position  of  the  hip,  pulls  it  downward  so  as  to  make  it 
convex  downward.  Hence,  in  palpation  of  the  abdomen,  as  well  as  in  the 
reduction  of  a  hernia,  the  thighs  are  flexed  on  the  pelvis,  which  relaxes 
the  traction  of  the  fascia  lata  on  Poupart's  ligament  and  the  muscles 
and  aponeuroses  connected  with  it,  and  thus  relaxes  the  abdominal 
walls.  In  addition,  the  stomach,  bowels,  and  bladder  should  be  empty 
to  facilitate  palpation. 

Poupart's  ligament  corresponds  to  the  inguinal  fold,  and  is  an  impor- 
tant landmark  in  the  surgical  anatomy  of  hernia,  as  well  as  in  the  opera- 
tions performed  in  the  iliac  region  of  the  abdominal  parietes.  Some  of 
its  fibers  pass  nearly  horizontally  backward  to  be  attached  to  the  inner 
2.5  cm.  (1  in.)  or  so  of  the  iliopubic  line.  These  form  Gimbernat's  liga- 
ment, whose  free,  concave,  external  margin  is  at  the  inner  border  of  the 
crural  canal  (see  p.  304).  The  latter  ligament  forms  part  of  the  septum 
between  the  pelvis  and  the  thigh. 

Internal  to  the  pubic  spine  the  fibers  of  the  external  oblique  apon- 
eurosis are  attached  to  the  crest  of  the  pubis.  But  some  of  its  fibers, 
known  as  the  triangular  fascia,  cross  the  median  line,  decussating  with  fibers 
of  the  aponeurosis  of  the  opposite  side,  pass  behind  and  strengthen  the 
internal  pillar  and  the  inner  end  of  the  opposite  external  abdominal  ring, 
and  are  attached  to  the  pubic  crest  and  the  iliopectineal  line  of  that  side, 
in  connection  with  Poupart's  and  Gimbernat's  ligament  and  in  front  of 
the  conjoined  tendon. 

The  semilunar  line  (see  also  p.  268)  indicates  the  line  along  which  the 
abdominal  aponeuroses  divide  to  form  the  sheath  of  the  rectus.  Along 
this  line,  lying  between  the  rectus  and  the  fleshy  portion  of  the  lateral 
muscles,  the  abdominal  wall  is  composed  only  of  the  fibrous  tissue  of  the 
abdominal  aponeuroses,  except  above  where  fleshy  fibers  of  the  trans- 
versalis pass  behind  it.  It  is  devoid  of  large  vessels,  except  inferiorly  where 
the  deep  epigastric  vessels  cross  it,  hence  it  is  sometimes  chosen  for  inci- 
sion or  paracentesis. 

It  is  concave  mesially,  corresponding  to  the  outer  border  of  the  rectus. 
The  upper  end  of  the  line  is  at  or  slightly  internal  to  the  point  where 
the  gall-bladder  comes  in  contact  with  the  abdominal  wall.  Above  a 
level  3.5  cm.  (1J  in.)  below  the  umbilicus,  the  semilunar  line  nearly  cor- 
responds to  a  vertical  line  erected  from  the  middle  of  Poupart's  ligament. 

The  sheath  of  the  rectus  (Fig.  98)  is  formed  by  the  aponeuroses  of  the 
three  lateral  muscles.  The  aponeurosis  of  the  internal  oblique  splits 
along  the  semilunar  line  to  pass  partly  in  front  with  that  of  external 


PLATE  XXIX 


FIG.  97 


SUPERFICIAL    LAYER, 
SUPERFICIAL    FASCIA 


DEEP    LAYER, SUPER- 
FICIAL   FASCIA 


TRANSVERSALIS 

MUSCLE 
INT.    OBLIQUE 

MUSCLE 
TRANSVERSALIS 

FASCIA 
PERITONEUM 


EXT.    OBLIQUE 
APONEUROSIS 


LIAC    FASCIA 


UBPERITONEAL- 
TISSUE 


Sagittal  Section  of  Anterior  Abdominal  Wall  through  the  Outer 
Half  of  Poupart's  Ligament.     (Tillaux.) 


FIG.  98 


SHEATH    OF 
RECTUS 


SUPERFICIAL 
FASCIA 


EXTERNAL 
OBLIQUE 


TRANSVERSAL. 
FASCIA 


PERITONEUM 


Diagrammatic  Transverse  Section  of  Anterior  Abdominal  Wnl 

.J<.»essel.) 


Upper  figure  above,  lower  figure  below  the  lemilunar  fold  <>i  Do 


THE  ANTERIOR  ABDOMINAL   WALL  27.') 

oblique  and  partly  behind  the  muscle  with  that  of  the  transversalis. 
This  arrangement  holds  in  the  upper  three-fourths  of  the  muscle,  but 
in  the  lower  fourth,  a  little  above  midway  between  the  umbilicus  and  the 
symphysis,  all  three  aponeuroses  pass  in  front.  The  lower  border  of  the 
dorsal  part  of  the  sheath  formed  by  the  aponeuroses  is  concave  down- 
ward, and  known  as  the  semilunar  fold  of  Douglas.  Below  this  a  delicate 
fascia,  continuous  with  the  fold  of  Douglas,  passes  down  behind  the 
rectus  to  the  bladder  (fascia  Retzii),  in  addition  to  the  transversalis 
fascia,  which  is  here  firm  and  thickened  and  takes  the  place  of  the  dorsal 
layer  of  the  sheath. 

At  the  fold  of  Douglas  the  deep  epigastric  vessels  pass  within  the 
rectus  sheath  in  their  upward  course.  From  the  extremities  of  the  folds 
of  Douglas  thickened  bands  or  pillars  descend,  the  inner  pillar  to  the 
symphysis,  the  outer,  or  "ligament  of  Hesselbach"  (Braune),  splits  to 
enclose  the  internal  abdominal  ring,  being  attached  internally  to  the 
horizontal  ramus  of  the  pubis  (and  to  the  pectineal  fascia),  and  externally 
to  the  iliac  fascia  (over  the  psoas)  and  to  the  transversalis  muscle  where 
it  arises  from  Poupart'.s  ligament. 

The  aponeurotic  layers  which  form  the  ventral  and  dorsal  layers  of 
the  sheaths  of  the  recti  uniting  along  their  median  borders  to  complete 
the  sheaths  join  one  another  to  form  a  median  fibrous  raphe,  the  linea 
alba  (see  also  p.  268).  From  the  ensiform  cartilage  to  and  a  little  below 
the  umbilicus  it  is  wide,  apparent,  and  easily  found,  measuring  about 
6  mm.  (\  in.)  in  width  below  the  ensiform  cartilage  and  16  mm.  (f  in.) 
near  the  umbilicus.  Below  the  umbilicus  it  rapidly  narrows,  and 
thence  down  to  the  symphysis  the  sheaths  of  the  two  recti  coalesce 
and  it  is  merely  the  narrow  fibrous  interval  between  them.  This  fibrous 
interval  may  be  difficult  to  find,  and  in  fact  it  may  be  said  that  there  is 
practically  no  linea  alba  below  the  umbilicus,  and  that  it  is  rarely  possible 
to  incise  hen-  without  exposing  the  margins  of  one  or  both  recti  muscles, 
SO  that  the  knife  need  only  follow  the  median  line  and  disregard  the  linea 
alba.  Just  above  the  symphysis  the  linea  alba  expands  into  a  narrow 
triangular  band,  the  adininiciiliini,  only  visible  on  the  dosral  surface  of  the 
abdominal  wall.  The  interval  between  the  two  muscles  is  slightly  more 
marked  just  above  the  symphysis  in  front  also,  so  that  it  has  been  sug- 
gested to  incise  from  below  upward  in  this  part  of  the  linea  alba,  for  the 
■  ii  thai  it  may  be  more  easily  found. 

In  pregnancy  or  in  abdominal  distention  from  other  causes  the  linea 

alba  becomes  much  wider,  owing  to  the  separation  of  the  recti,  reaching 
'i  cm.  :;  J  '"■ '  ;,t  ''"'  umbilicus  and  •':  cm.  1 1 1  in.  |  at  the  narrowest  pari 
Cruveflhier).  In  an  otherwise  healthy  child  I  have  also  observed  such 
;i  congenital  diasta  ii  ><<  die  recti,  with  n  corresponding  widening  of  the 
linea  alba  and  ;i  slight  umbilical  hernia,  thai  the  fingers  could  readily 
I..-  thrust  between  the  recti,  belo*  the  umbilicu  \  similai  condition 
may  exisl  in  "pot-bellied/'  rickety  children.  In  such  cases  a  ventral 
hernia  ma)  occa  ionallj  occur  between  the  two  recti  muscles.  Ventral 
hernia  of  the  linea  alba,  when  no!  po  toperative,  is  usually  due  to  the 
enlargement  of  rmall  opening   which  exisl  normally,  some  of  them  for  ma 


276  THE  ABDOMEN 

passage  of  small  nerves  and  vessels.  Such  a  hernia  should  not  be  con- 
founded with  small  lipomata  which  may  grow  from  the  subperitoneal 
tissue  through  these  openings. 

The  fibrous  tissue  composing  the  linea  alba  is  thin  and  compact, 
and  cannot,  as  a  rule,  be  separated  into  layers  corresponding  to  the  three 
aponeuroses  which  unite  from  either  side  to  form  it.  As  there  are  no 
vessels  of  any  size  in  the  linea  alba,  it  is  often  selected  for  incision  or 
paracentesis. 

Contraction  of  the  muscles  of  the  abdominal  wall  make  the  latter  as 
hard  as  a  board.  In  this  condition  they  protect  the  viscera  within  from 
sudden  movement  or  pressure  in  acute  peritonitis,  or  from  a  blow.  If 
a  blow  is  expected  the  instinctively  contracted  and  rigid  abdominal 
muscles  protect  the  viscera  from  injury  like  a  firm  but  elastic  rubber 
plate,  though  they  themselves  may  be  bruised  or  even  torn.  On  the 
contrary,  an  unexpected  blow  upon  a  flaccid  abdomen  may  seriously 
wound  a  viscus  without  visibly  affecting  the  belly  wall,  the  latter  escaping 
injury  by  being  very  freely  movable  over  the  viscera.  It  is  impossible  to 
tell  the  severity  of  the  blow  or  the  seriousness  of  the  injury  from  outward 
inspection.  In  such  cases  a  thick  padding  of  fat  in  the  belly  wall  or 
omentum  helps  to  protect  the  viscera  from  injury. 

On  account  of  the  tonic  contraction  of  the  abdominal  muscles  a  posi- 
tive pressure  {intra-abdominal  pressure)  normally  exists  in  the  abdomen. 
This  pressure  is  increased  by  the  descent  of  the  diaphragm  in  inspiration, 
and  by  straining,  lifting,  coughing,  etc.,  which  favor  the  production  of  a 
hernia  and  the  protrusion  of  the  abdominal  viscera  through  a  pene- 
trating wound  of  the  belly  wall.  Diminution  of  this  pressure  and 
weakness  of  the  muscles  which  cause  it  are  important  elements  in 
constipation,  difficult  labor,  pelvic  and  abdominal  displacements  in 
women,  etc. 

The  transversalis  fascia,  not  to  be  confounded  with  the  transversalis 
aponeurosis,  lines  the  deep  surface  of  the  transversalis  muscles  and  their 
anterior  aponeuroses,  and  is  continuous  with  the  fascia  lining  the  other 
parts  of  the  abdominal  walls. 

It  is  very  thin  above  the  umbilical  level,  where  it  passes  up  to  become 
continuous  with  a  delicate  fascia  on  the  under  surface  of  the  diaphragm 
and  laterally  it  is  continuous  with  the  anterior  layer  of  the  lumbar  fascia. 
Below  the  umbilicus  it  becomes  thicker  and  firmer  as  we  trace  it  down- 
ward, and  here  it  is  important  in  strengthening  the  abdominal  wall 
where  the  tendency  to  hernia  is  greatest.  This  is  especially  so  mesially, 
where  it  supplies  the  place  of  the  posterior  sheath  of  the  rectus  below  the 
semilunar  fold  of  Douglas,  and  laterally  between  the  inner  half  of  Pou- 
part's  ligament  and  the  conjoined  tendon,  where  it  is  very  strong  and 
strengthens  an  otherwise  weak  spot. 

It  is  attached  to  the  inner  lip  of  the  iliac  crest  and  to  the  outer  half 
of  Poupart's  ligament,  blending  with  the  iliac  fascia.  Beneath  the  inner 
half  of  Poupart's  ligament,  to  which  it  is  but  loosely  attached,  it  is 
thickened  by  transverse  fibers  to  form  the  deep  femoral  arch,  and  is  con- 
tinued down  into  the  thigh  to  form  the  front  of  the  femoral  sheath.    More 


THE  ANTERIOR  ABDOMINAL   WALL  277 

internally  it  is  attached  to  the  iliopectineal  line,  behind  the  conjoined 
tendon,  and  to  the  pubic  crest,  where  it  is  continuous  with  the  pelvic  fascia. 

In  the  male,  a  pouch  of  this  fascia  shaped  like  a  funnel,  hence  called 
the  infundibuliform  fascia,  descends  in  fetal  life  with  the  peritoneal  pro- 
cessus vaginalis  along  the  inguinal  canal  into  the  scrotum,  forming  one  of 
the  coverings  of  the  spermatic  cord  and  the  testis.  After  the  descent  of 
the  testis  this  pouch  contracts,  so  that  it  closely  surrounds  the  cord  in  its 
passage  through  the  inguinal  canal,  leaving  a  slight  depression  with  a 
crescentic  mesial  border  at  the  internal  ring,  where  the  fascia  is  called 
infundibuliform.  As  the  transversalis  fascia  lines  the  anterolateral 
abdominal  walls,  no  hernia  can  occur  here  without  receiving  a  covering 
from  it. 

In  incisions  this  fascia  may  possibly  be  mistaken  for  the  peritoneum, 
and  the  subperitoneal  fat  beneath  it  for  the  underlying  omentum. 

This  fascia  will  direct  the  course  of  an  abscess,  etc.,  lying  superficial 
to  it.  Such  an  abscess  would  be  disposed  to  spread  downward,  where 
it  would  be  checked  by  and  point  above  the  attachment  of  the  fascia  to 
the  iliac  crest  and  the  outer  half  of  Poupart's  ligament,  or  more  internally 
it  might  run  along  the  inguinal  canal  into  the  scrotum. 

The  subperitoneal  (or  extraperitoneal)  connective  tissue  is  a  delicate 
layer  of  loose  connective  tissue  containing  a  varying  amount  of  fat, 
which  separates  the  parietal  peritoneum  from  the  fascia  lining  the 
abdominal  walls. 

Along  the  linea  alba  and  at  the  umbilicus  it  binds  the  transversalis 
fascia  and  peritoneum  closely  together.  Elsewhere  it  is  more  loose  and 
abundant,  and  its  looseness  favors  the  spread  of  abscess,  etc.,  on  the 
one  hand,  and  on  the  other  hand  allows  the  peritoneum  to  be  stripped 
up  from  the  fascia  in  extraperitoneal  operations  on  the  iliac  vessels, 
ureter,  etc. 

Owing  to  the  ease  with  which  this  tissue  allows  the  peritoneum  to 
be  stripped  up,  care  is  required  to  avoid  this  in  abdominal  incisions, 
especially  where  the  peritoneum  is  adherent  to  the  parts  beneath  or  is 
thought  to  be,  but  has  not  been  incised.  Thus  in  some  ovarian  cysts 
the  peritoneum  has  been  mistaken  for  the  cyst  wall  and  widely  stripped 
up.  The  presence  of  this  tissue,  especially  when  thick  or  containing  fat, 
is  useful  as  a  landmark  in  abdominal  incisions  to  indicate  that  the 
peritoneum  has  been  reached.  It  should  be  borne  in  mind  that,  in  some 
and  localities,  the  amount  of  fni  may  be  considerable  so  as  not  to 
mistake  it  for  the  omentum,  as  sometimes  happens.  The  amount  of 
fat  is  greatest  in  the  inguinal,  iliac,  and  lumbar  regions,  in  the  latter 
furnishing  the  perinephritic  fat. 

It  erves  <<>  annuel  those  viscera  having  an  incomplete  or  imperfect 
peritoneal  covering  with  the  abdominal  parietes,  and  in  such  places 
supports  a  delicate  anastomp  is  between  the  parietal  and  visceral  ves- 
-  -h.  as  in  the  liver,  kidney-.,  pancreas,  duodenum,  vertical  parts  of  the 
colon,  rectum,  bladder,  etc. 

Infection  may  extend  from  these  organs  or  from  an  external  wound  into 
thi    ti    ue,  where  it  readily    pread  .  usually  in  the  direction  of  gravity. 


278  THE  ABDOMEN 

Thus  an  abscess  from  a  neglected  appendicitis  may  extend  in  the  sub- 
peritoneal tissue  of  the  iliac  fossa  to  Poupart's  ligament,  where  it  may 
dissect  off  and  displace  upward  the  parietal  peritoneum  and  form  a  large 
abscess  that  can  be  opened  without  opening  the  peritoneum,  as  was 
done  before  the  modern  operation  for  appendicitis  (Fig.  107). 

The  looseness  of  this  tissue  allows  the  upward  displacement  of  the 
parietal  peritoneum  just  above  the  symphysis,  when  a  distended  bladder 
rises  out  of  the  pelvis,  and  thus  permits  the  extraperitoneal  tapping  or 
opening  of  the  bladder  anteriorly.  In  front  of  the  bladder  it  is  rich  in  fat, 
and  forms  the  loose  tissue  of  the  "Cavum  Retzii."  At  the  upper  end  of 
the  crural  canal  it  forms  the  septum  crurale,  and  it  descends  along  the 
inguinal  canal  to  form  a  delicate  covering  of  the  cord,  the  testis,  or  a 
hernia.  Its  adipose  tissue  is  the  starting  point  of  subserous  lipomata, 
which  may  push  through  small  openings  of  the  overlying  parts,  as  in  the 
linea  alba,  and  simulate  an  irreducible  hernia. 

At  the  internal  abdominal  ring,  especially  on  its  inner  side,  this  tissue 
contains  a  considerable  amount  of  fat  which,  if  it  be  absorbed  or  dimin- 
ished from  any  cause,  may  leave  a  depression  which  favors  the  formation 
of  a  hernia.    Its  looseness  favors  the  formation  of  the  hernial  sac. 

A  rare  form  of  preperitoneal  hernia  may  occur  in  this  tissue,  i.  e., 
between  the  peritoneum  and  the  transversalis  fascia.  The  subperi- 
toneal connective  tissue  forms  a  perivascular  sheath  for  the  large  vessels 
which  lie  in  it,  and  accompanies  them  outside  the  abdomen. 

The  Parietal  Peritoneum  is  described  later  (see  p.  317). 

Vessels  and  Nerves  of  the  Anterior  Abdominal  Wall. — Arteries. — 
The  superficial  arteries  (superficial  epigastric  and  circumflex  iliac)  are 
branches  of  the  femoral  and  lie  between  the  layers  of  the  superficial 
fascia.  They  are  of  little  importance,  although  Verneuil  has  reported 
a  case  of  bleeding  from  the  superficial  epigastric  resulting  fatally. 

Of  the  deep  arteries,  the  deep  epigastric,  a  branch  of  the  external 
iliac,  is  the  most  important.  Where  it  reaches  the  anterior  abdominal 
wall,  just  above  Poupart's  ligament,  it  lies  behind  the  inguinal  canal, 
just  internal  to  the  internal  abdominal  ring  and  a  little  above  and  to 
the  outer  side  of  the  femoral  ring.  The  vas  deferens  in  the  male,  and 
the  round  ligament  in  the  female,  loop  over  it  just  internal  to  the  inter- 
nal ring  and  draw  it  slightly  inward.  Its  direction  may  be  marked 
off  by  a  line,  slightly  curved  inward,  from  the  outer  end  of  the  inner 
third  of  Poupart's  ligament  to  a  point  2.5  cm.  (1  in.)  or  so  external  to  the 
umbilicus,  crossing  the  lateral  edge  of  the  rectus  one-third  of  the  distance 
between  the  pubic  crest  and  the  level  of  the  navel.  In  this  line  paracen- 
tesis should  not  be  performed,  for  hemorrhage*  from  this  artery  might 
be  free  in  the  loose  tissue  in  which  it  lies,  inferiorly. 

In  its  course  it  lies  at  first  lateral  to  the  rectus  and  then  behind  it. 
At  first  it  is  embedded  in  the  subperitoneal  connective  tissue,  then  it 
pierces  the  transversalis  fascia,  and  passing  within  the  sheath  of  the  rectus 
at  the  fold  of  Douglas  it  lies  behind  the  fleshy  fibers  of  the  rectus,  midway 
between  its  borders,  and  finally  within  the  muscle,  where  it  anastomoses 
with  the  superior  epigastric  branch  of  the  internal  mammary  artery. 


THE  ANTERIOR  ABDOMINAL  WALL  279 

Besides  the  latter  artery,  small  branches  derived  from  the  two  lower 
intercostals,  the  lumbar  and  the  circumflex  iliac  arteries  are  found  in  the 
abdominal  parietes.  Xo  artery  of  the  anterolateral  abdominal  parietes 
is  of  such  size  or  importance  as  alone  to  contra-indicate  a  given  incision, 
but  it  is  well  to  bear  in  mind  the  course  of  the  deep  epigastric  artery  and 
that  it  crosses  the  semilunar  line. 

Veins. — The  deep  set  of  veins  are  the  paired  vence  comites,  accom- 
panying the  deep  arteries,  in  like  manner  with  which  they  anastomose 
with  one  another  as  well  as  with  the  plexus  in  the  subperitoneal  tissue 
and  a  parumbilical  rein,  which,  passing  along  the  round  ligament  of  the 
liver  to  that  organ,  connects  the  portal  veins  with  the  deep  epigastric. 

The  subcutaneous  or  superficial  set  are  single  and  do  not  exactly  fol- 
low the  corresponding  arteries.  The  superficial  epigastric  vein  is  often 
seen  through  the  skin.  It  anastomoses  with  the  deep  and  the  superior 
epigastric  veins  and  thereby  with  the  parumbilical  and  portal  veins,  and 
also  with  a  subcutaneous  vein  (v.  tkoracico-epujastrica)  which  runs  up 
the  side  of  the  thorax  to  join  the  axillary  vein.  This  thoracico-epigastrie 
vein  may  be  continued  independently  into  the  femoral  instead  of  or  as 
well  as  joining  the  superficial  epigastric. 

The  surface  veins  may  become  enormously  dilated  or  varicose,  to  the 
size  of  the  little  finger,  and  so  become  very  distinct.  This  condition 
(caput  medusa?)  usually  depends  upon  their  affording  a  collateral  cir- 
culation in  obstruction  of  the  inferior  cava  or  the  portal  veins,  although 
this  varicosity  may  exist  without  any  such  obstruction,  and,  vice  versa, 
the  obstruction  may  exist  without  any  varicosity.  Fig.  120  shows  the 
mechanism  of  this  and  other  varicosities  in  portal  congestion. 

Although  it  has  been  shown  from  the  arrangement  of  the  valves  that 
the  current  in  these  surface  vessels  above  the  navel  is  toward  the  axilla, 
and  in  those  below,  toward  the  groin,  yet  when  the  veins  arc  dilated  the 
valves  become  insufficient  and  the  current  can  take  an  abnormal  course. 
In  portal  obstruction  the  current  in  the  superficial  epigastric  is  toward 
the  groin,  where  it  empties  into  the  femoral  or  the  internal  saphenous, 
anil  in  caval  obstruction  the  current  is  in  the  reverse  direction  and  passes 
into  the  axillary  or  innominate  through  the  thoracico-epigast  picor  superior 
epigastric  veins. 

The  direction  of  the  current  is  determined  by  emptying  the  veins  and 

allowing  them  to  fill,  and  is  a  point  that  may  be  Utilized  in  diagnosis. 

Lymphatics.  As  to  the  superficial  lymphatics,  those  above  a  level 
SOmewhai  above  the  umbilicus  go,  with  those  of  the  breast,  to  the  axillary 
nodes;  those  below   this  level,  to  the  inguinal  nodes. 

Tin-  drrp  lymphatics  accompany  the  parietal  vessels  to  the  iliac  and 
sternal  glands. 

Nerves.  The  nerves  supplying  the  anterolateral  abdominal  wall  are 
the  lower  seven  thoracic  nerves,  and  the  iliohypogastric  and  ilio-inguinal 

branches  of  the  firs(  lumbar  nerve.  The  sensory  supply  of  the  skin  is 
furnished  by  the  anterior  divisions  of  the  lateral  cutaneous  branches 
and  the  anterior  cutaneous  branches  of  the  lower   even  thoracic  nerves 

and  by  the  bvpogS   trie  branch  of  the  HiohvpOga    trie  n<i\«-. 


280  THE  ABDOMEN 

The  sixth  and  seventh  nerves  supply  the  skin  over  the  "pit  of  the 
stomach,"  the  eighth  nerve  corresponds  to  the  middle  linea  transversa, 
the  tenth  to  the  umbilicus,  the  distribution  of  the  twelfth  (or  subcostal) 
extends  to  within  5  cm.  (2  in.)  of  the  symphysis,  that  of  the  iliohypo- 
gastric is  below  this. 

The  muscles  of  this  region  of  the  abdominal  parietes  are  supplied  by 
branches  from  the  same  nerves,  with  the  exception  of  the  sixth  thoracic 
and  the  addition  of  a  few  filaments  from  the  ilio-inguinal  nerve. 

The  anterior  portions  of  these  nerves  pass  between  the  transversalis 
and  internal  oblique  muscles  to  the  outer  border  of  the  sheath  of  the 
rectus,  which  they  pierce  to  supply  the  muscle,  within  which  they  give 
off  the  anterior  cutaneous  branches.  The  fact  that  these  numerous 
nerves  supply  the  abdominal  muscles,  makes  their  position  and  direction 
of  importance  in  planning  incisions. 

These  nerves  are  placed  at  fairly  equal  distances  apart,  and  pass 
downward  and  inward  in  the  lower  third  of  the  ventral  abdominal  wall 
(i.  e.,  the  eleventh  and  twelfth  thoracic,  the  iliohypogastric,  and  the 
ilio-inguinal  nerves),  nearly  transversely  inward  in  the  middle  third 
(i.  e.,  ninth  and  tenth  thoracic  nerves),  and  somewhat  upward  and  inward 
in  the  upper  third  (i.  e.,  the  seventh  and  eighth  thoracic  nerves). 

According  to  Brewer  the  course  of  the  twelfth  thoracic  nerve  is  indi- 
cated by  a  line  from  a  point  12  mm.  (^  in.)  below  the  tip  of  the  twelfth 
rib  to  the  spine  of  the  pubis  on  the  opposite  side;  that  of  the  eleventh 
thoracic  nerve  by  a  line  from  a  point  12  mm.  (^  in.)  below  the  tip  of  the 
eleventh  rib  to  the  middle  of  Poupart's  ligament  on  the  opposite  side; 
that  of  the  tenth  thoracic  nerve  from  a  point  12  mm.  (^  in.)  above  the  tip 
of  the  eleventh  rib  to  the  anterior  superior  iliac  spine  of  the  opposite  side. 
The  line  indicating  the  course  of  the  ninth  nerve  is  from  a  point  just 
below  the  osteochondral  junction  of  the  ninth  rib  horizontally  inward, 
that  of  the  eighth  thoracic  nerve  is  from  a  point  just  below  the  outer 
end  of  the  eighth  cartilage  horizontally  inward  to  a  point  12  mm.  Q  in.) 
to  the  median  side  of  the  chondral  border  and  then  upward  and  inward 
parallel  with  the  border  and  12  mm.  Q-  in.)  internal  to  it.  In  great 
abdominal  distention  or  obesity  these  lines  would  not  hold. 

The  lower  nerves  run  somewhat  more  transversely  than  the  fibers 
of  the  external  oblique  and  its  aponeurosis,  so  that  they  are  in  some 
danger  of  injury  even  by  oblique  incisions  parallel  to  these  fibers,  as  in 
operations  for  appendicitis,  but  they  may  be  spared  with  a  little  care. 
Vertical  incisions  of  any  length,  save  in  or  near  the  median  line,  cannot 
avoid  exposure  and  division  of  one  or  more  of  these  nerves.  Division 
of  these  nerves  results  in  paresis  of  that  part  of  the  abdominal  muscles 
which  is  supplied  by  the  nerves  divided,  and  this  paresis  causes  a  weakness 
and  bulging  of  the  abdominal  walls  and  increases  the  tendency  to  hernia. 
The  direction  of  the  nerves  is  nearly,  if  not  quite,  parallel  to  the  cleavage 
lines  of  the  skin. 

An  inflammation  (perineuritis)  of  one  or  more  of  these  nerves  causes 
pain  in  the  area  of  distribution,  and  may  be  accompanied  or  followed 
by  a  vesicular  cutaneous  eruption  limited  to  the  same  area  and  known 


THE  ANTERIOR  ABDOMINAL  WALL  281 

as  herpes  zoster  (gtooTTjp,  a  girdle),  or  shingles.  Pain  or  modified  sen- 
sation (a  sense  of  constriction  or  tightness)  in  the  area  of  distribution 
may  also  be  caused  by  pressure  on  these  nerve  trunks  from  injury, 
tumors,  or  tuberculosis  of  the  spine  or  spinal  cord.  Thus  many  cases 
have  been  recorded  where  a  commencing  Pott's  disease  has  been  mis- 
taken or  treated  for  "bellyache,"  or  for  trouble  in  the  kidneys  or  bladder 
when  the  lower  nerves  are  involved.  The  position  of  the  spinal  segment 
affected  by  disease  or  injury  may  be  localized  by  the  sensory  area  or 
the  muscles  involved. 

The  lower  thoracic  nerves,  besides  furnishing  the  motor  and  sensory 
nerve  supply  to  the  abdomen,  also  supply  the  intercostal  muscles  and 
the  costal  pleurae.  This  accounts  for  the  fact  that  the  pain  of  a  pleurisy, 
especially  when  near  the  base  of  the  lung,  is  often  referred  to  the  abdo- 
men, particularly  by  children  who  seem  to  have  less  ability  to  locate 
pain  than  adults.  The  abdominal  muscles  are  concerned  with  the  inter- 
costal muscles  in  the  movements  of  respiration.  The  association  of  the 
sensory  nerves  of  the  abdomen  with  the  motor  nerves  of  the  inspiratory 
muscles  is  illustrated  by  the  violent  inspiration  or  deep  gasp  given  when 
cold  water  is  thrown  upon  the  belly.  The  lower  ribs  are  fixed  by  the 
reflex  contraction  of  the  abdominal  muscles  so  that  this  inspiration  is 
confined  to  the  upper  ribs. 

On  account  of  the  association  in  the  same  nerve  of  the  sensory  and 
motor  fibers,  the  reflex  contraction  of  the  abdominal  muscles  occurs 
more  rapidly  than  if  these  fibers  were  in  separate  nerves.  The  sensory 
nerves  are  thus  enabled  to  do  the  duty  of  a  sentinel,  to  give  warning  that 
can  be  immediately  acted  upon  by  the  motor  nerves  by  contracting  the 
muscles.  This  is  an  important  provision,  for,  as  we  have  already  seen, 
the  viscera  are  well  protected  from  contusions  only  when  the  muscles 
are  first  contracted.  The  rapidity  of  the  reflex  contraction  is  well  seen 
when  ;i  cold  hand  is  laid  upon  the  abdomen.  Rigidity  of  the  abdominal 
muscles  is  immediately  caused,  so  that  satisfactory  abdominal  palpation 
cannot  be  practised  unless  the  hands  be  warm. 

A  surface  lesion  like  a  bum,  when  rendered  painful  by  exposure  to 
the  air,  causes  the  abdominal  walls  to  become  rigid.  Not  only  painful 
surface  lesions,  but  also  painful  visceral  or  deep  lesions,  like  visceral 
injuries   and    peritonitis,   cause    by    reflex    action   a    tonic   rigidity   of  the 

muscles  or  a  muscular  spasm  on  pressure,  so  as  to  afford  complete  rest 

to  the  inflamed  surfaces.    This  is  one  of  the  mosl  important  diagnostic 

of  a  local  or  general  peritonitis.    The  patient  with  peritonitis  may 

also  be  unable  to  tolerate  the  leasl  pressure,  even  of  the  bedclothes,  such 

IS  the  reflex  sensitiveness  of  the  skin. 

The  explanation  of  this  reflex  lies  in   the  fad    thai    the  lower  seven 

thoracic    and    the    firsl    lumbar    spinal    segments,    whose    spinal    nerves 

supply    the   abdominal    parietes,  also   supply    the   abdominal   viscera 

through    the   corresponding  sympathetic  ganglia   and    the  splanchnic 

derived  from  them.    Tin-  latter  nerves  enter  the  rolar  and  other 

.(ted  plexu  es  which  provide  the  nerve  supply  of  the  abdominal 

.  i  ,,,;,.    The  "referred  pain  "  of  visceral  disease  are  due  to  the  irritation 


282  THE  ABDOMEN 

of  segments  of  the  cord  by  the  sympathetic  filaments  of  the  affected 
viscera.  This  irritation  produces  sensory  impulses  which  are  referred  by 
the  brain  to  the  surface  distribution  of  the  segments  involved  (from 
which  sensory  impulses  usually  come),  and  not  to  their  point  of 
origin. 

Reference  to  Fig.  199  shows  the  areas  of  cutaneous  distribution  to  the 
abdominal  wall  of  the  sixth  thoracic  to  the  second  lumbar  spinal  seg- 
ments. These  areas  may  be  sensitive  to  the  touch  or  the  seat  of  referred 
pains  in  lesions  of  the  viscera  whose  nerve  supply  is  connected  with  the 
same  segments.  Thus,  according  to  Head,  the  stomach  is  associated 
with  the  6  to  10  (inch)  thoracic  segments,  the  intestines  with  the  9  to  12 
(inch)  thoracic  segments,  the  liver  and  gall-bladder  with  the  7  to  10  (inch) 
thoracic  segments,  the  kidney  and  ureter  with  the  tenth,  eleventh,  and 
twelfth  thoracic  and  first  lumbar  segments. 

Congenital  Defects  of  the  Abdomen. — During  fetal  life  the  lateral 
abdominal  walls,  as  they  grow,  bend  inward  to  meet  and  unite  in  the 
median  line,  which  they  do  last  of  all  at  the  umbilicus.  In  so-called 
extroversion  (or  exstrophy)  of  the  bladder  this  median  union  has  failed 
in  the  lower  part,  where  the  base  and  posterior  wall  of  the  bladder,  whose 
front  wall  is  wanting,  is  thrust  forward  by  the  viscera  beneath,  so  as  to 
appear  at  or  in  front  of  the  level  of  the  skin  as  a  red  area  of  mucous 
membrane,  moistened  by  urine  trickling  from  the  visible  opening  of  the 
ureters.  This  condition  is  usually  associated  with  absence  of  the  sym- 
physis pubis  and  with  epispadias. 

Again,  a  failure  of  the  parietes  to  unite  mesially  may  result  in  a  pro- 
trusion of  the  viscera,  especially  near  the  umbilicus,  varying  in  size  from 
a  small  hernia  to  one  involving  all  the  movable  viscera. 

Injuries  and  Wounds  of  the  Abdominal  Wall. — In  contusions  the 
fact  should  be  remembered  that  ecchymosis  may  not  occur  even  though 
the  contusion  be  severe,  and  that  when  the  muscles  are  contracted  the 
viscera  are  likely  to  escape  injury.  A  blow  on  the  abdomen  should  never 
be  considered  trivial  and  refused  treatment  until  after  sufficient  time 
has  elapsed  without  symptoms  to  exclude  the  possibility  of  visceral  injury. 
A  blow  on  the  epigastrium  may  be  followed  by  sudden  death  without  caus- 
ing marks  of  parietal  or  visceral  injury.  The  fatal  result  is  probably 
due  to  an  inhibitory  action  on  the  heart  from  a  concussion  of  the  solar 
plexus. 

The  important  distinction  in  wounds  of  the  abdomen  is  between  pene- 
trating and  non-penetrating  wounds.  In  the  former  the  peritoneum  is 
wounded  and  their  seriousness  depends  upon  infection,  either  from  with- 
out or  from  a  visceral  wound,  and  upon  hemorrhage.  The  subjacent 
viscera  may  escape  injury  because  the  weapon  does  not  reach  them  or, 
in  rare  instances,  the  intestines  have  escaped  injury  from  a  bullet  or  a 
weapon  thrust  among  them. 

If  infection  of  an  abdominal  wound  occurs,  the  loose  connective  tissue 
between  the  several  layers  and  the  space  between  the  rectus  and  the  rear 
wall  of  its  sheath  favor  the  spread  of  inflammation  and  of  pus.  The 
number  of  layers  and  the  loose  tissue  between  many  of  them  makes  it 


THE  ANTERIOR  ABDOMINAL   WALL  283 

very  easy,  in  probing  a  bullet  or  stab  wound,  for  the  probe  to  leave  the 
track  of  the  wound  and  pass  between  the  layers  of  muscles  or  fasciae. 
Hence,  probing  such  wounds  is  unsatisfactory  and  is  to  be  condemned. 

On  account  of  the  different  direction  of  the  fibers  of  the  several  muscle 
layers  their  retraction  in  a  wound  or  incision  is  in  different  directions,  so 
that  an  irregular  wound  results.  The  contraction  of  the  muscles  may 
favor  the  protrusion  of  the  viscera  through  such  a  wound,  and,  in  replacing 
them,  care  should  be  taken  not  to  push  them  into  the  spaces  between  the 
muscles  or  beneath  the  peritoneum.  It  is  important  and  sometimes 
difficult  to  apply  the  sutures  so  that  the  cut  edges  of  each  of  the  muscular 
layers  are  in  apposition,  and  unless  this  is  done  the  strength  of  the  wall 
is  impaired.  It  is  also  of  the  utmost  importance  that  the  peritoneum  on 
the  two  sides  of  the  wound  should  be  sutured  so  as  to  bring  about  its 
speedy  union,  otherwise  a  gap  is  left  on  its  surface,  which  favors  the 
formation  of  a  hernia  at  the  site  of  the  wound.  The  constant  movement 
of  the  abdominal  wall  does  not  allow  that  rest  which  is  so  favorable  or 
even  essential  to  wound  healing,  but  in  spite  of  this  most  wounds  heal 
well  here. 

Operations  and  Incisions. — Operations  are  practised  upon  all  the 
abdominal  viscera,  and  for  exploration  or  diagnosis.  The  position  of 
the  incision  varies  with  the  viscus  to  be  approached.  The  general  rule 
that  the  incision  should  give  free  access  and  avoid  wounding  nerves  and 
large  or  important  vessels  is  to  be  followed,  but  in  addition  the  danger 
of  subsequent  hernia  is  to  be  considered.  This  danger  is  greater  in  the 
lower  part  of  the  abdomen,  for  here  gravity  adds  to  the  protruding  force 
of  the  intra-abdominal  pressure,  due  to  muscular  action.  Also,  as  Hyrtl 
says,  aponeurosis  is  less  resistant  than  muscle  and  a  scar  in  the  former 
is  more  likely  to  yield  than  one  in  the  latter. 

Incisions  (Fig.  99). — Incisions  may  be  directed  vertically,  or  obliquely. 
Vertical  incisions  an-  most  commonly  practised  along  the  two  fibrous 
or  aponeurotic  lines,  the  linea  alba  and  the  linen  semilunaris.  Through 
the  latter  line  we  may  expose  the  appendix  veruiifonnis,  the  kidney,  the 
colon,  the  gall-bladder,  and  the  bile  ducts;  but  the  incision  is  objection- 
able because  it  divides  nerves  that  supply  a  part  of  the  rectus  muscle,  and 

the  scar  is  in  relatively  thin  fibrous  tissue  and  is  liable  to  yield  and  be 
followed  by  hernia. 

Of  course,  in  ome  CS  es,  other  considerations  (greater  safely,  vie.) 
may  outweigh    the  objections.      The  danger  of  hernia   may   be   lessened 

by  incising  the  sheath  of  the  rectus  muscle  I  t<>  -.'>  cm.  i '  to  I  in.  I  internal 

to  it     outer  border,  retracting  the  muscle  inward  and  dividing  the  deep 

laser  of  the  sheath  in  line  with  the  incision  of  the    uperficial  layer,  thus 

forming  a  trap-door  incision.     In  tin-  upper  part  of  die  linea  semilunaris 

the  Incision  is  not  through  fibrou    ii   lue  only,  bui  we  meet  with  the 

fibei    of  the  transversalifl  mu  cle,  which  here  pa   les  behind 

the  rectus. 

Of  all    incisions,  thai    in  or   mar   the   linen   all>u    is    the   ino  .1    common 

It  fa  practised  in  mo  I  operatioi the  pelvic  viscera,  in  mosl  explora- 
tory operations,  and   in  many  others.     The  following  advantagt 


284 


THE  ABDOMEN 


claimed  for  incisions   through  the  linea  alba:    (1)  slight  vascularity; 
(2)  few  important  structures  to  be  divided;  (3)  accessibility  to  all  parts. 

1.  The  slight  vascularity  is  a  disadvantage,  for  it  delays  rapid  and 
firm  healing  and  so  predisposes  to  hernia. 

2.  Hernia  is  also  favored  by  the  comparatively  thin  scar  resulting 
from  the  few  blended  structures  divided  and  sutured.  The  incision  is 
also  more  difficult  to  make,  as  it  is  hard  to  tell  its  exact  depth  at  any  given 
stage  for  want  of  landmarks.  Moreover,  if  we  have  to  extend  the  median 
incision  past  the  umbilicus  we  encircle  it,  usually  on  the  left,  because  of 
the  danger  of  wounding  the  parumbilical  vein,  sometimes  of  large  size, 

Fig.  99 


Abdominal  incisions:  1,  median  incision  in  linea  alba;  2,  Kammerer  incision  (appendicitis); 
3,  McBurney  incision  (appendicitis);  4,  median  incision  encircling  umbilicus  to  left  to  avoid 
parumbilical  vein  and  round  ligament;  5,  oblique  incision  parallel  to  right  costal  margin  (gall- 
bladder), Kocher's  incision  is  parallel  and  a  little  lower;  6,  Bevan's  incision  (gall-bladder); 
7,  Mayo  Robson's  incision  (gall-bladder);  8,  posterior  gastro-enterostomy;  9,  gastrostomy 
(Witzel,  Kader,  Senn);    10,  median  incision,  gastrectomy  (partial). 

which  passes  along  the  round  ligament  of  the  liver  to  the  right  of  the 
median  line.  But  as  it  is  difficult  to  render  the  umbilicus  aseptic  there  is 
danger  of  infecting  the  incision  or  the  track  of  the  sutures  which  unite 
this  part  of  the  incision.  The  above  disadvantages  of  incisions  in  the 
linea  alba  are  avoided  and  the  advantages  shared  by  an  incision  through 
the  rectus  muscle  about  2  cm.  (-|  in.)  from  the  median  line,  separating 
bluntly  the  fibers  of  the  muscle  or  retracting  it  outward  in  the  manner  of 
a  trap-door.  The  muscle  and  its  sheath  are  then  sutured  separately. 
The  linea?  transversa  offer  no  serious  obstacle  to  the  vertical  separation 
of  the  fibers  of  the  rectus  muscle  (see  also  p.  272). 

In  the  epigastrium  the  stomach  is  well  exposed  by  a  vertical  incision, 


THE  ANTERIOR  ABDOMINAL   WALL  285 

which  may  be  median  or  through  the  inner  half  of  the  rectus  muscle. 
Occasionally  an  oblique  incision  along  the  costal  margin  external  to  the 
rectus  is  employed. 

Transverse  or  somewhat  oblique  incisions  in  the  rectus  above  the  umbili- 
cus are  not  objectionable,  if  properly  united,  for  they  only  increase  the 
number  of  linese  transversa  and  are  not  likely  to  wound  the  nerves.  But 
they  are  more  difficult  to  suture,  so  that  the  vertical  incisions  are  here 
preferred.  Below  the  umbilicus  we  should  bear  in  mind  the  position  of 
the  deep  epigastric  artery  in  transverse  section  of  the  rectus. 

The  transverse  incision  just  above  the  pubes  to  expose  the  bladder  appears 
to  offer  little  or  no  advantage  over  the  vertical,  and,  unless  properly  healed, 
it  is  likely  to  impair  the  function  of  the  muscle  as  well  as  to  lead  to  ventral 
hernia. 

In  the  area  outside  of  the  linear  semilunares  the  best  incisions  are  those 
directed  obliquely,  parallel,  or  nearly  parallel,  with  the  cleavage  lines  of 
the  skin  and  the  direction  of  the  nerves.  Here  the  incisions  are  through 
a  thin  muscular  wall  which,  if  properly  united,  affords  more  protection 
against  hernia  than  those  through  thinner  aponeurotic  structures. 

In  the  lower  half  of  this  area  we  commonly  incise  parallel  to  the  fibers 
of  the  external  oblique  and  its  aponeurosis,  i.  e.,  at  right  angles  to  a  line 
joining  the  anterior  superior  iliac  spine  and  the  umbilicus.  Separating 
the  external  oblique  fibers,  we  may  reach  the  transversalis  fascia  by  blunt 
separation  of  the  internal  oblique  and  transversalis  muscles,  which  are 
practically  in  the  same  line.  To  facilitate  this  blunt  separation  a  thin 
membranous  sheath  on  the  outer  surface  of  the  internal  oblique  should 
be  incised  in  the  line  of  the  proposed  separation.  As  this  separation  of 
the  muscular  layers  according  to  the  direction  of  their  fibers  is  in  a  dif- 
ferent line  from  that  of  the  aponeurosis,  we  may  not  get  quite  as  much 
room  from  a  given  length  of  skin  incision  as  if  we  incised  the  muscles. 
But  by  varying  the  direction  and  force  of  the  retraction  of  the  edges  of 
the  wound  almost  an  equal  amount  of  room  is  obtained.  Moreover,  we 
can  readily  enlarge  the  intermuscular  incision  by  incising  the  sheath 
of  the  rectus  toward  the  median  line  and  retracting  the  muscle  in  the 
same  direction.  The  blunt  intermuscular  incision  is  an  almost  absolute 
safeguard  againsl  hernia,  as  the  muscles  come  naturally  together  and 
close  the  wound,  and  the  more  the  muscles  contract  the  closer  conic  the 
edges  <>f  the  wound.  It  is  useful  for  colostomy  on  the  left  as  well  ;is  for 
appendectomy  on  the  right  side. 

In  tin-  upper  'part  of  this  area,  ;ni  oblique  incision,  nearly  parallel 
with  the  costal  margin,  is  nearly  in  line  with  the  nerves  and  cleavage 
line-,  of  the  -l-.in,  permits  the  blunl  separation  of  the  interna]  oblique 
and  gives  n  fairly  good  exposure  of  the  parts  about  the  liver  on  the  right 

lide  ;iik1   the  -toinaeh  or  spleen  oil  the  left  side. 

To  expose  the  liver,  gall-bladder,  etc.,  an  oblique  incision  from  a 

point  below  and  external  to  the  ensiform  cartilage,  12  mm.  i'  in.)  or 

more  to  the  inner  id.-  of  the  CO  ital  margin,  tO  a  point  half  an  inch  aho\e 
the  tip  of  the  eleventh  fib  will  only  divide  the  ninth  ihoraeie  ner\e.  The 
same  i     trii'    of  a  vertical  mci   ion  through  the  middle  or  outer  pari  of  the 


286  THE  ABDOMEN 

rectus  muscle  from  a  point  12  mm.  (^  in.)  below  the  lower  border  of  the 
eighth  costal  cartilage  to  a  point  5  cm.  (2  in.)  above  the  umbilicus.  For 
the  same  purpose  Bevan's  incision  is  serviceable,  consisting  of  a  vertical 
incision,  along  the  outer  border  of  the  right  rectus,  whose  lower  end  may 
be  prolonged  obliquely,  outward,  near  the  level  of  the  umbilicus,  and 
whose  upper  end,  18  mm.  (f  in.)  below  the  costal  margin,  may  be  pro- 
longed obliquely  inward  and  upward  by  incising  the  sheath  of  the  rectus 
and  retracing  the  muscle.  When  much  room  is  required  for  the  safety 
of  an  operation  the  incision  must  be  enlarged  or  added  to  where  and  in 
what  way  it  is  necessary,  but  in  general  the  above  considerations  should 
apply.  For  local  anesthesia  the  most  suitable  incisions  are  the  incision 
in  the  linea  alba  and  the  oblique  incision  at  the  sides,  for  there  are  no  nerve 
trunks  in  the  former  and  the  latter  incision  is  parallel  with  them. 

The  Regions  of  the  Abdomen. — The  abdomen  has  been  arbitrarily 
divided  into  nine  regions,  so  that  the  viscera  of  these  regions  may  be 
localized  with  reference  to  the  surface  area  of  these  regions.  Of  course, 
the  relation  of  the  viscera  to  the  overlying  surface  is  only  approximate, 
for  the  position  of  the  viscera  has  a  wide  range  of  physiological  variation 
in  different  subjects  or  in  the  same  subject  at  different  times.  This 
regional  division  may  be  of  service  in  medical  education,  but  in  practice 
we  determine  the  position  of  viscera  by  palpation,  etc.,  and  by  reference 
to  well-defined  landmarks. 

To  aid  the  more  precise  description  of  the  position  of  pathological  or 
medicolegal  findings  the  regions  might  be  of  more  service.  Unfortunately 
there  is  confusion  and  variation  instead  of  uniformity  in  the  boundaries 
of  these  nine  regions,  so  that  the  method  is  useless  for  accurate  descrip- 
tion. 

The  two  vertical  and  the  two  horizontal  planes  which  mark  off  these 
regions  must  be  fixed  with  reference  to  landmarks  easily  located  on  the 
living  body. 

As  usually  described,  the  vertical  planes  pass  through  the  middle  of 
the  inguinal  (Poupart's)  ligament,  and  nearly  correspond  with  the  linese 
semilunares  in  the  two  upper  zones. 

The  upper  horizontal  plane  is  best  drawn  as  a  subcostal  plane  connecting 
the  lowest  points  of  the  tenth  costal  cartilages  of  each  side. 

The  lower  horizontal  plane,  as  usually  given,  passes  through  the  two 
anterior  superior  iliac  spines. 

It  is  as  important  to  know  the  viscera  which  are  cut  by  these  planes 
as  the  viscera  in  the  areas  bounded  by  them. 

The  vertical  planes  cut  from  below  upward  on  the  right  side,  the  apex 
of  the  cecum,  small  intestine,  transverse  colon,  kidney,  and  gall-bladder 
(often) ;  and  on  the  left  side,  the  sigmoid  flexure,  small  intestine,  kidney, 
transverse  colon,  pancreas,  stomach,  and  spleen. 

The  upper  horizontal  plane  passes  through  the  second  (or  third)  lumbar 
vertebra  behind,  and  runs  5  cm.  (2  in.)  above  the  umbilicus  in  front. 
The  viscera  cut  by  it  are  the  stomach,  transverse,  ascending  and  de- 
scending colons,  duodenum  (lower  curve),  both  kidneys,  and  the  small 
intestine. 


THE  ANTERIOR  MiDoUIXM.  }YM.L 


287 


The  lower  horizontal  plane  (interspinous)  passes  at  about  the  level  of 
the  top  of  the  sacral  promontory  and  cuts  the  cecum,  small  intestine,  and 
sigmoid  flexure. 

The  names  and  visceral  contents  of  the  nine  regions  marked  off  by 
the  above  planes  may  be  seen  in  the  following  table.  The  adjacent  parts 
of  the  lower  iliac  and  hypogastric  regions  form  the  inguinal  region. 


Right. 
R.  Hypochondriac. 

Liver,  greater  part  of 
right  lobe.  Gall-bladder, 
part  of  fundus  (some- 
times').  Kidney,  upper 
and  outer  part.  Colon, 
hepatic  flexure  and  part 
of  ascending  colon. 


Middle. 
Epigastric. 

Liver,  whole  or  greater 
part  of  Left  lobe,  pari  of 
right  lobe.  Must  or  all 
of  gall-bladder.  Stomach, 
middle  and  pyloric  re- 
gions, bol  h  orifices.  Intes- 
tines; duodenum,  first  and 
second  portions  and  end 
of  third  portion.  Small 
intestine.  Transverse  colon 
(part  of).  Pancreas,  head 
and  body.  Spleen,  upper 
and  inner  part.  Kidneys, 
upper  and  inner  part. 
Adrenals. 


Left. 
L.  Hypochondriac. 

Liver,  sometimes  part  of 
left  lobe.  Stomach,  fundus. 
Spleen.,  greater  part.  Pan- 
creas, tail.  Kianey,  upper 
and  outer  part.  Colon, 
splenic  flexure,  and  part 
of  descending  colon. 


Horizontal  Plane  at  Level  of  Lowest  Point  op  the  Tenth  Costal 

Cartilages. 


Right  Lumbar. 

Kidney,  lower  and  outer 
part;  intestine;  ascending 
colon;  cecum  (part  of)  ; 
vermiform  appendix 
(often) ;  part  of  ileum  and 
its  termination. 


Umbilical. 

Kidneys,     lower     and 
inner  port  ion  wit  ii  ureters; 
tine,  t  bird  pari  duod- 
enum:    part     01    jejunum 

and  ileum;  greater  part  of 

Ira  nriif.e     colon;     part      Of 

sigmoid  flexure. 


Left  Lumbar. 

Kidney,  lower  and  outer 
part;  intestine,  jejunum; 
part  of  descending  colon; 
part,  of  sigmoid  flexure 


Horizontal  Plane  at  Level  of  Anterioh  Stjperiob  [liac  Spines. 
Right  Iliac.  Hypogastric.  Left  Iliac. 


Intestine;    ileum,    part 
of;  cecum,  lower  part  of; 
form  appendix. 


Intestine,    small    in  Intestine;      small     in- 

tines;  part  of  sigmoid  testine :  part,  of  sigmoid 
flexure,  upper  part  of  flexure. 
rectum;  tip  of  cecum, 
usually;  vermiform  ap- 
pendix 'often).  Bladder 
in  children  and,  when  dis- 
tended, in  adult  s.  '  %  /•"  , 
fundus  and  appendagt  . 

The  Umbilicus  and  Umbilical  Hernia.  In  early  fetal  life  there  vaaa 
through  the  umbilical  opening,  which  is  bordered  by  fibers  of  the  linea 
alba,  the  urachus,  the  umbilical  arteries  and  vein,  and  a  loop  of  small 
Intestine.  Oustide  of  the  body  thee  are  bound  together  by  embryonic 
Wharton's  jelly)  and  covered  with  amnion  to  form  the  umbilical 
cord.     Later  the  intestinal  loop  retracts  within  the  abdomen,  leaving 


288  THE  ABDOMEN 

within  the  cord,  for  a  time,  the  vitello-intestinal  duct,  which  connects  the 
end  of  the  loop  with  the  yolk  sac.  The  proximal  end  of  this  duct  may 
persist  as  a  finger-like  process,  Meckel's  diverticulum,  connected  with  the 
lower  end  of  the  ileum,  from  30  to  90  cm.  (1  to  3  ft.)  from  the  ileocecal 
valve. 

Occasionally,  from  imperfect  development,  the  fetal  condition  per- 
sists at  birth,  and  a  loop  of  intestine  or  an  intestinal  diverticulum  pro- 
jects a  variable  distance  through  the  umbilical  ring  into  the  cord.  This 
constitutes  a  congenital  umbilical  hernia.  If  care  is  not  exercised  in  tying 
the  cord,  this  projection  may  be  tied  or  cut  off,  causing  a  fecal  fistula,  which 
may  be  proceded  by  obstruction  if  an  intestinal  loop  is  tied.  Two  or  more 
cases  of  such  an  accident  are  on  record.  More  rarely  the  hernial  protru- 
sion is  larger  and  contains  a  larger  mass  of  intestine  or  other  viscera  with 
a  thin  covering. 

At  birth  the  cord  is  tied  a  short  distance  from  the  belly  wall  and  the 
proximal  end  shrivels,  dries  up,  and  in  about  five  days  drops  off  at  the  same 
spot  in  all  cases,  i.  e.,  the  level  of  the  abdomen,  no  matter  where  the  liga- 
ture is  applied.  This  is  accounted  for  by  the  sphincter-like  arrangement 
of  elastic  fibers  around  the  umbilicus  (especially  on  its  deep  aspect), 
which  contract  arid  shut  off  like  a  ligature  the  vessels  passing  through  the 
ring,  including  those  supplying  the  cord  itself. 

At  birth  and  for  some  time  afterward  a  distinct  ring  can  be  felt  at  the 
umbilicus.  At  the  spot  where  the  stump  of  the  cord  separates  from  the 
belly  wall  a  scar  forms  which  binds  together  the  stumps  of  the  umbilical 
vessels.  The  skin  rapidly  grows  over  this  scar,  which,  when  it  contracts, 
throws  the  surface  into  folds,  forming  the  umbilical  papilla.  It  is  on 
account  of  the  creases  between  the  folds  that  it  is  so  difficult  to  make  the 
umbilicus  aseptic  before  operation. 

As  we  look  at  this  puckered  scar  from  behind  we  see  the  converging 
obliterated  umbilical  arteries  and  the  median  urachus  running  to  it  from 
below  (Fig.  101)  and  the  empty  umbilical  vein  running  upward  from  it. 
At  first  there  is  a  slight  depression  in  the  centre  of  the  contracting  ring, 
into  which  there  is  a  little  projection  of  peritoneum.  During  infancy  a 
hernia  may  protrude  through  the  cicatrix,  not  jet  firm,  in  the  still  open 
ring,  between  the  arteries  and  the  vein,  or  above  the  latter.  This  is  known 
as  infantile  umbilical  hernia.  It  occurs  in  the  first  few  months  of  infancy, 
and  is  due  to  frequent  coughing,  crying,  or  straining  on  account  of  con- 
stipation, phimosis,  etc.  If  properly  treated  by  being  kept  reduced  it 
usually  heals  without  operation,  for  the  cicatricial  contraction  of  the  ring 
can  then  go  on  to  final  closure. 

The  umbilical  vessels  having  become  obliterated  and  reduced  to 
fibrous  cords  in  the  first  month  of  infant  life,  the  abdomen  grows  more 
rapidly  than  these  obliterated  vessels,  which,  therefore,  pull  upon  the 
umbilical  cicatrix.  The  traction  of  the  two  obliterated  arteries  and  the 
urachus  is  stronger  than  that  of  the  vein,  so  that  the  fibrous  cords  repre- 
senting all  three  vessels  are  pulled  down  to  the  lower  margin  of  the  umbili- 
cus. The  upper  half  of  the  scar  is  thin,  while  the  vessel  cicatrix,  in  the 
lower  half,  becomes  the  strongest  part  of  the  umbilicus  and  the  latter 


THE  ANTERIOR  ABDOMINAL   WALL  289 

the  strongest  point  in  the  abdominal  wall.  Consequently,  in  adult  life 
an  acquired  umbilical  hernia  either  protrudes  through  the  upper  part  of  the 
reopened  ring  or  altogether  above  it,  and  is  in  reality  a  hernia  of  the  linea 
alba,  on  the  lower  aspect  of  which  appears  the  umbilical  cicatrix.  This 
form  of  hernia  occurs  most  commonly  in  women  after  repeated  preg- 
nancies and  in  very  stout  individuals,  owing  to  the  stretching  of  the 
abdominal  walls  in  both  classes  of  cases. 

On  the  deep  aspect  of  the  umbilicus,  in  about  two-thirds  of  the  cases 
examined,1  are  seen  transverse  fibers  passing  from  the  inner  border  of 
one  rectus  sheath  to  that  of  the  other.  ;They  are  known  as  the  fascia 
umbilicalis,  are  adherent  to  the  peritoneum,  cover  the  deep  surface  of 
the  umbilical  vein,  and  represent  a  thickening  of  the  transversalis  fascia. 
In  certain  cases  they  are  present  only  above  and  below  the  umbilicus, 
leaving  the  latter  free  and,  theoretically,  more  exposed  to  hernia.  But  as 
acquired  hernia  occurs  quite  uniformly  above  the  umbilicus,  the  common 
arrangement,  where  the  fascia  ends  by  a  free  margin  a  little  above  the 
cicatrix,  may  be  equally  favorable  to  hernia  formation. 

Richet2  likened  a  canal-like  space  above  the  umbilicus,  between  the 
linea  alba  and  this  fascia,  to  the  inguinal  canal  in  relation  to  hernia 
formation.    But  the  analogy  is  purely  an  imaginary  one. 

The  umbilical  papilla,  or  cutaneous  cicatrix  proper,  is  at  the  bottom 
of  a  depression  which  is  due  to  a  lack  of  subcutaneous  fat  in  and  im- 
mediately about  it.  It  corresponds  to  the  original  fibrous  ring  of  the 
umbilicus,  derived  from  the  tissues  of  the  linea  alba.  The  layers  of  the 
abdomen  in  this  cicatricial  area,  i.  e.,  skin,  aponeurotic  scar  tissue,  fascia 
transversalis,  and  peritoneum,  are  so  thin  and  closely  adherent  that,  when 
stretched  out  by  a  hernia,  we  can  hardly  avoid  opening  the  peritoneal 
sac,  unless  by  incising  well  above,  below,  or  laterally.  The  superficial 
fascia  is  practically  wanting. 

In  congenital  and  many  infantile  herniae  the  omentum  is  not  found  in 
the  sac,  for  at  this  period  it  has  not  developed  as  low  as  this.  In  the 
acquired  form  it  is  nearly  always  present  and  frequently  adherent.  The 
colon  is  often  present  and  incarceration  is  common. 

Coverings  of  Umbilical  Herniae.  -Congenital  herniae,  embryonic  tissue 
of  the  cord  and  an  amniotic  layer  continuous  with  the  skin  at  the  ring. 
There  is  no  true  sue 

Infantile  herniae,  peritoneum,  forming  tin-  sac,  transversalis  fascia, 
skin.    (The  superficial  fascia  i-  -<>  scanty  as  to  be  practically  wanting.) 

Acquired  herniae,  the  same  as  the  infantile  variety  with  the  addition  of  the 
superficial  fascia  and  tin-  fibrous  tissue  of  the  umbilical  scar  or  of  the 
linea  alba,  for,  as  a  nil--,  the  hernia  is  really  through  the  linea  alba  above 
tin-  scar. 

The  subperitoneal  tissue  is  so  small  in  amount  as  <<>  I"-  omitted,  for 
the  peritoneum  i->  here  very  adherenl  to  the  fascia. 

In  fetal  lite  the  urachus,  derived,  like  the  bladder,  from  the  stalk  of  the 
allantois,  ha    a  lumen  connected  with  that  of  the  bladder,  etc.    Accord- 

Inh.  AH,.,  Bu  I  '  A  "■■''•  '  Ururgloale,  6th  ed„  p.  745. 

19 


290  THE  ABDOMEN 

ing  to  Luschka,  a  total  obliteration  of  the  lumen  of  the  urachus  is  not  the 
rule,  but  an  unobliterated  part  is  usually  found.  This  may  be  con- 
nected with  the  bladder  or  shut  off  from  it.  Occasionally  such  a  patent 
portion  opens  as  a  fistula  at  the  umbilicus.  A  probe  passes  a  variable 
distance  down  the  urachus,  and  a  seromucous  secretion,  not  urine,  is 
discharged  from  the  opening  of  the  fistula.  I  have  met  with  a  few  such 
cases,  which  are  readily  closed  by  scraping  and  cauterization. 

A  few  cases  are  on  record  where  the  fetal  canal  of  the  urachus  has 
remained  open  from  the  bladder  to  the  umbilicus,  so  that  on  micturition 
the  urine  would  stream  from  the  latter  when  its  passage  through  the 
urethra  was  impeded.  In  case  of  stricture  of  the  urethra  its  function 
could  be  performed  by  such  a  urachus. 

Another  abnormal  condition  observed  is  a  reopening  of  the  urachus 
during  retention  of  urine,  thus  allowing  urine  to  escape  at  the  navel 
and  relieve  the  retention.  But,  as  Hyrtl  suggests,  it  is  not  unlikely  that 
in  such  a  case  the  urachus  was  patent  as  far  as  the  umbilicus.  Urinary 
calculi  have  also  been  found  in  the  urachus,  where  the  latter  connected 
with  the  bladder,  and  in  one  case  a  stone  was  removed  from  the  bladder 
by  the  aid  of  a  finger  passed  through  a  patent  urachus.  In  the  lower  part 
of  the  median  line  the  peritoneum  is  separated  from  the  abdominal  wall 
by  the  urachus,  so  as  not  to  be  in  direct  contact  with  it. 

The  Inguinal  Region  and  Inguinal  Hernia. — The  boundaries  of  this 
region  are  Poupart's  ligament  below,  a  horizontal  line  from  the  anterior 
superior  iliac  spine  above,  and  internally  the  median  line  or,  for  practical 
purposes,  the  outer  border  of  the  rectus  muscle.  The  several  layers  of  the 
belly  wall  are  essentially  the  same  here  as  elsewhere  anteriorly,  except  that 
(1)  the  intercolumnar  fibers  and  fascia  are  closely  joined  to  the  outer  surface 
of  the  external  oblique  aponeurosis,  and  (2)  the  conjoined  tendon,  repre- 
senting the  internal  oblique  and  trans versalis  muscles,  arches  over  from 
the  outer  half  of  Poupart's  ligament  to  the  iliopectineal  line  and  the  pubic 
crest.  This  leaves  bare  of  these  muscles  the  inner  half  of  the  ligament  and 
a  narrow  semilunar  space  above  it,  corresponding  to  the  inner  two-thirds 
of  the  inguinal  canal. 

The  superficial  inguinal  lymph  nodes  are  below  Poupart's  ligament 
over  Scarpa's  triangle  (see  p.  491). 

What  gives  this  region  its  importance  is  the  presence  of  the  inguinal 
canal,  an  oblique  passageway  through  the  abdominal  wall  for  the  sper- 
matic cord  in  the  male  and  the  round  ligament  in  the  female.  This 
canal,  like  many  others  in  the  body,  is  not  an  actual  but  a  potential  canal, 
a  breach  or  track  forming  a  weak  spot  in  the  abdominal  wall  along  which 
a  hernia  may  be  protruded.  An  open  canal  is  a  pathological  condition 
due  to  a  hernia,  etc. 

The  Inguinal  Canal. — The  inguinal  canal  in  the  male  is  formed  by  the 
passage  of  the  processus  vaginalis  and  the  testis  through  the  abdominal 
wall,  which  then  closes  down  snugly  on  the  spermatic  cord,  which  follows 
the  testis. 

It  should  be  remembered  that  the  testis,  etc.,  does  not  break  through 
each  layer  as  a  bullet  through  a  board,  but  the  several  layers  are  evagi- 


THE  ANTERIOR  ABDOMINAL   WALL  291 

nated  as  a  pouch  before  it  and  stretched  out  to  form  a  laminated  cover- 
ing of  the  testis  and  the  cord. 

The  peritoneal  pouch,  evaginated  with  the  musculofascial  layers 
through  what  is  to  be  the  inguinal  canal,  forms  the  processus  vaginalis. 
This  precedes  the  descent  of  the  testis  through  the  canal.  The  testis  is 
from  the  outset  outside  of  the  peritoneum,  having  developed  behind  it, 
so  that  it  descends  alongside  of  and  outside  of  the  processus  vaginalis 
through  the  inguinal  canal  and  so  into  the  scrotum.  (See  Scrotum  and 
Testes.) 

The  two  ends  or  openings  of  the  canal  are  called  the  abdominal  rings. 
The  inferior  and  mesial  one  is  known  as  the  external  ring  because  it  is 
superficial,  though  more  internal  or  mesial  than  the  internal  ring. 

The  External  or  Superficial  Abdominal  Ring. — The  external  or  super- 
ficial abdominal  ring  is  where  the  cord,  or  round  ligament,  passes  through 
the  aponeurosis  of  the  external  oblique  and  spreads  apart  two  fasciculi 
of  this  aponeurosis  called  pillars  of  the  ring.  A  triangular  gap  is  thus 
formed  with  its  base  downward  and  inward  over  the  spine  and  outer  part 
of  the  crest  of  the  os  pubis.  The  lower  and  outer  fasciculus  or  "pillar" 
of  the  ring  blends  with  and,  in  fact,  is  the  inguinal  (Poupart's)  ligament. 
It  is  attached  to  the  pubic  spine  internally  and  the  fascia  lata  below.  It  is 
the  stronger  and  more  posterior  pillar,  and  on  it  rests  the  cord  or  round 
ligament.  The  upper  and  inner  "pillar"  is  attached  to  the  pubic  crest. 
So-called  intercolumnar  fibers,  arching  upward  and  inward  between  the 
two  pillars,  bridge  across  and  round  off  the  outer  angle  where  the  two 
pillars  meet,  and  bind  the  latter  securely  together  so  as  to  prevent  their 
further  separation.  These  intercolumnar  fibers  are  joined  together  by  a 
thin  membrane  into  a  fascia,  the  intercolumnar  fascia.  From  the 
margins  of  the  ring  this  fascia  is  prolonged  over  the  cord  and  testes 
as  the  external  spermatic  fascia.  It  represents  the  attenuated  covering 
furnished  by  the  external  oblique  aponeurosis. 

The  base  of  the  triangular  gap  is  rounded  off  by  the  triangular  fascia, 
lying  at  a  deeper  level  than  the  ring,  and  sometimes  known  as  the  pos- 
terior pillar.  Thus  the  external  ring  is  oval,  with  its  long  diameter  ob- 
liquely vertical.  It  lies  2  to  .'5  cm.  (1  in.)  from  the  median  line,  above  and 
jusl  Int.  nil  to  the  pubic  spine,  and  can  n-adily  be  felt  by  invaginating 
the  scrotum  with  the  finger  and  following  up  the  t'ronf  of  the  cord. 

li  averages  2.5  cm.  <l  in.)  by  12  nun.  {h  in.),  though  its  size  is  very 
variable  and  it  is  smaller  in  the  female  than  in  the  male.  In  cases  of  non- 
desceni  of  the  testis,  or  after  its  removal,  the  external  ring  may  be  nar- 
rowed or  even  obliterated.  Normally  ii  will  admit  die  tip  of  the  index 
finger  iii  the  adult,  thai  of  the  little  finger  in  the  child.  It  is  felt  to  be 
r,ilar<]c<l  iii  flexion,  adduction,  and  inward  rotation  of  the  thigh  by  means 

of  the  relaxation  of  the  fascia  lata  and  thereby  of  Poupart's  ligament,  the 
rnal  pillar,  which  is  attached  to  this  fascia.  I  fence  the  thigh  is  placed 
in  this  position  f<>r  taxis  or  for  examination  of  the  canal,  also  to  see  if  a 
tin  or  bandage  fits  snugly  enough  to  retain  a  hernia.  Vice  versa,  it  is 
narrowed  in  extension,  abduction  and  outward  rotation  of  the  thigh  by 

the  traction  of  the  fascia  lata  making  lense  (lie  external  oblique  aponeu- 


292 


THE  ABDOMEN 


{<■ 


EXT.   OBLIQUE 
APONEUROSIS 
INT.  OBLIQUE 
MUSCLE" 


M 


:ritoneum 


RANSVERSALIS 
FASCIA 

RANSVERSALIS 
MUSCLE 


rosis.    This  position  is  one  which  may  be  employed  after  operations  for 
hernia. 

The  Internal  or  Deep  Abdominal  Ring. — The  internal  or  deep  abdominal 
ring  is  where  the  cord  passes  through  the  transversalis  fascia,  which  is 
here  called  the  infundibuliform  fascia,  because  it  has  formed  a  funnel- 
shaped  pouch  for  the  testis  and  still  presents  a  slight  pit  or  depression. 
The  inner  fascial  margin  of  this  depression  forms  a  prominent  crescentic 

edge,  due  to  the  traction  of  the 
Fig.  ioo  vas  deferens  as  it  bends  inward 

and  downward  into  the  canal. 

This  ring  lies  somewhat  over 
12  mm.  (^  in.)  above  Poupart's 
ligament  at  a  point  slightly  in- 
ternal to  its  centre.  It  is  oval  in 
shape,  with  its  long  diameter 
directed  vertically.  The  trans- 
versalis fascia  is  not  broken 
through  by  the  passage  of  the 
testis,  but  is  one  of  the  layers  of 
the  pouch  evaginated  to  receive 
it,  and  forms  the  infundibuliform 
or  internal  spermatic  fascia, 
whose  upper  opening,  the  in- 
ternal ring,  is  closed  around  the 
cord  or  round  ligament. 

The  Inguinal  Canal. — The  in- 
guinal canal,  extending  obliquely 
between  these  two  rings,  meas- 
ures 4  to  5  cm.  (l-§-  to  2  in.)  in 
length  in  the  male  and  5  cm. 
(2  in.)  in  the  female.  Its  direc- 
tion is  somewhat  more  vertical 
than  Poupart's  ligament,  and  its 
oblique  passage  through  the  ab- 
dominal wall  serves  as  a  valve 
to  lessen  the  chance  of  a  hernia 
entering  it.  Its  size  varies  with 
that  of  the  cord  or  round  liga- 
ment which  occupies  it,  hence  it  is  smaller  in  the  female.  The  right  canal 
averages  larger  than  the  left,  a  fact  that  may  help  to  explain  the  prepon- 
derance of  hernia  on  the  right  side. 

Walls  of  the  Canal  (Fig.  100). — In  front  lie  the  aponeurosis  of  the 
external  oblique  and,  in  the  outer  third,  the  lower  fleshy  fibers  of  the 
conjoined  tendon.  These  same  fibers  arch  above  it.  Behind  lie  the  trans- 
versalis fascia  and,  opposite  the  inner  half  of  the  external  ring,  the  con- 
joined tendon  and  the  triangular  ligament.  Above  it  is  the  conjoined  ten- 
don, below  is  the  gutter  formed  by  the  junction  of  Poupart's  ligament  and 
the  transversalis  fascia,  above  which  lies  the  cord  at  a  distance  which 


m 


FASCIA    LATA- 


Sagittal  section  of  anterior  abdominal  wall  through 
the  middle  of  the  inguinal  canal.    (Tillaux.) 


PLATE  XXX 


FIG.   101 


M.  iliacu 


External 
iliac 
artery 


Extern 

i/iae 

vein. 


External 

inguinal 

fOSSO. 


Jitter, ml  imjninai 
Jussa. 


'emiirtil 

JllSSIt. 

Superior  vesical 

artery. 

\Mlildle  iiuiniiidl 

fossa. 


Posterior  View  of  the  Anterior1  Aluloi ;il   Wall    In    its    Lower 

Half.     (After  Joessel.) 


The  peritoneum  i    in  place,  and  the  variou    cord    *n  through. 


THE  ANTERIOR  ABDOMINAL  WALL 

increases,  as  we  proceed  outward,  to  12  mm.  fj  in.)  or  more  at  the  internal 
ring.  In  this  space  we  may  incise  to  open  iliac  i  sea  or  expose  the 
external  iliac  artery. 

Fat  is  abundant  in  the  subperitoneal  tissue  behind  the  rear  wall  of  the 
canal,  so  that  masses  of  fat  are  commonly  found  adherent  to  the  outer 
surface  of  the  neck  of  a  hernial  sac,  especially  on  its  mesial  side. 

Lying  in   this    -ubperitoneal   tissue   are   the   deep  epigastric   w- 
structure s  of  great  practical  importance,  which  pass  behind  the  canal  just 
mesial  to  the  internal  ring.    Between  the  internal  ring  and  these  l 
the  transversalis  fascia  is  very  strong;  internal  to  the  vessels,  where  a 
direct  hernia  makes  its  way  forward,  it  is  much  weaker. 

Besides  the  front  walls  of  the  canal  as  i  given,  other  tissue  layers, 

derived  from  the  layers  of  the  abdominal  wall  which  formed  the  i      g 
nated  pouch,  form  the  coverings  of  the  spermatic  cord  or  of  a  hernia. 
Thus  the  infundibuliform  portion  of  the  transrersalis  fascia  is  prolonged 
down  the  canal  as  a  tubular  covering  of  the  cord,  etc.,  and  the  lower 
-  of  the  internal  oblique,  in  the  conjoined  tendon,  spread  out  in  front 
and  at  the  sides  of  the  cord,  as  the  cremasteric  muscle  and  fascia.     I 
sionally  the  pouch  is  evaginated  between  instead  of  beneath  these  fibers, 
in  which  case  the  cremaster  is  found  behind  as  well  as  in  front  and  at  the 
of  the  cord,  testis,  etc. 
iinal  hernia  is  the  passage  of  one  or  more  of  the  abdominal  vis- 
cera through,  or  partly  through,  the  abdominal  wall,  following  in  whole 
or  in  part  the  inguinal  canal.    When  complete,  it  emerges  at  the  external 
ring.    They  comprise  9£  1  per  cent,  of  all  hernia?  in  the  male  a: 

to  60  per  cent,  in  the  female.     There  are  tun  principal  groups  of  inguinal 
hernia?,  according  as  the  point  at  which  they  pass  through  the  tra: 
salis  fascia  lies  external  or  internal  to  tht 

Inguinal  Fossae  (Fig.  1<>1  .  As  we  look  at  the  peritoneal  surface 
of  the  alnlominal  wall  in  the  inguinal  region  we  see  on  each  side  two 
longitudinal  ridges  or  folds  of  the  peritoneum,  which  _•   toward  a 

n  fold,  due  to  the  urachus,  as  the;  I  toward  the  umbilicus. 

The  most  lateral  fold  i>  tht  .  a  fold  of  peritoneum  «•!.- 

taied  by  the  deep  epigastric  artery  ami  forming  the  lateral  boundary 
of  //•  rial  boundary  i-  the  outer 

•  r  the  middle  line  is  t 

lue  to  the  obliterated  1: 
In  the  inguinal  region  thx  •  '1  folds  man 

ternal   to   the  ic  fold  i>  tin-  external  inguinal  fossa, 

at  the  bottom  of  which  w.  ped  depression  of  tin-  jx-n- 

.-,,,  uhi(;  the  interna]  abdominal  ring.    Thi 

ritoiM-ui  usually  ova  within 

and  looping  around  tb  J11'"" 

ic   folds    is  the  middle  inguinal  fossa,  which 
all  of  the  ii ._ 

irt  of  th< 

ic  fold  and  t;  :  teT™[ 


294  THE  ABDOMEN 

inguinal  or  supravesical  fossa,  corresponding  to  the  inner  half  of  the  external 
ring. 

When  a  hernia  pushes  through  in  the  external  fossa  we  call  it  an 
external,  indirect  or  oblique  inguinal  hernia;  when  in  the  middle  or 
internal  fossa,  it  is  known  as  an  internal  or  direct  inguinal  hernia.  These 
two  primary  varieties  of  inguinal  hernia  are  named  internal  and  external 
with  reference  to  the  relation  of  the  neck  of  their  sacs  to  the  deep  epi- 
gastric artery,  and  direct  and  indirect  or  oblique  with  reference  to  their 
straight  or  oblique  course  through  the  parietes.  The  resistance  of  the 
abdominal  wall  is  less  at  these  fossae  than  elsewhere. 

External,  Indirect  or  Oblique  Inguinal  Hernia. — These  follow  the 
course  of  the  inguinal  canal.  They  constitute  95  to  97  per  cent,  of  ingui- 
nal hernise.  An  incomplete  hernia,  or  one  not  passing  beyond  or  only 
just  beyond  the  external  ring,  is  called  a  bubonocele  from  the  bubo-like 
swelling.  A  complete  hernia  sooner  or  later  descends  into  the  scrotum,  and 
is  called  scrotal.  At  the  external  ring,  as  in  the  canal,  it  lies  in  front  and 
slightly  to  the  outer  side  of  the  cord,  which  it  follows  to  the  scrotum.  The 
coverings  of  such  a  hernia  are  the  same  as  those  of  the  cord  in  the  same 
situation,  i.  e.,  skin,  superficial  fascia,  intercolumnar  fascia  (also  called 
external  spermatic  fascia),  cremasteric  fascia,  infundibuliform  fascia 
(sometimes  called  internal  spermatic  fascia).  The  last  three  layers  form 
what  is  sometimes  known  as  the  fascia  propria,  a  term  of  no  great  impor- 
tance. The  serous  sac  is  derived  from  the  peritoneum  at  the  bottom  of 
the  external  fossa,  and  is  separated  from  the  fascial  layer  by  subserous 
tissue. 

These  hernise  are  pear-shaped,  with  the  small  end  above,  at  the  narrow 
oblique  neck  in  the  canal.  The  contents  are  not  characteristic;  almost 
any  of  the  lower  movable  viscera  may  be  within  the  sac.  Small  intestine 
(enterocele)  is  commonly  found,  omentum  (epiplocele)  often,  and  the 
latter  is  apt  to  adhere  to  the  sac  and  make  the  contents  irreducible.  Not 
infrequently,  especially  in  congenital  hernise,  the  cecum  and  appendix 
are  found  in  hernise  on  the  right  side  and  occasionally  on  the  left  side. 
A  part  of  the  bladder  is  occasionally  found  in  a  hernia  (p.  421). 

Despite  the  long  and  oblique  course  of  the  neck  of  external  inguinal 
hernia?,  in  a  canal  whose  muscular  walls  would  naturally  tend  to  close 
it,  and  despite  the  more  direct  course  of  internal  inguinal  hernise  through 
an  anatomically  weak  part  of  the  abdominal  wall,  the  former  occur  much 
more  commonly.  They  are  especially  common  in  early  life,  and  this  fact, 
as  well  as  their  greater  frequency,  is  to  be  explained  in  great  measure  by 
congenital  conditions.  In  fetal  life  one  ring  lies  in  front  of  the  other,  to 
facilitate  the  passage  of  the  testis,  so  there  is  scarcely  any  canal.  In  early 
childhood  the  inguinal  canal  passes  more  directly  and  less  obliquely 
through  the  abdominal  wall  than  in  the  adult,  a  fact  which  favors  the 
formation  of  hernia.  The  adult  obliquity  of  the  canal  is  acquired  only 
after  the  development  of  the  pelvis  is  completed. 

Varieties  of  Externnl  Oblique  Inguinal  Hernia  due  to  Congenital  Defects  in 
the  "  Vaginal  Process." — After  the  testis  has  reached  the  scrotum,  in  the 
eighth  month  of  fetal  life,  the  neck  and  upper  part  of  the  peritoneal 


THE  AXTERIOR  ABDOMIXAL   WALL 


295 


pouch,  the  processus  vaginalis,  tend  to  become  closed,  down  to  the  upper 
end  of  the  epididymis.  It  is  normally  reduced  to  a  small  cord  of  fibrous 
tissue,  lying  among  the  elements  of  the  cord,  which  is  attached  to  the 
bottom  of  the  funnel-shaped  depression  of  peritoneum  in  the  external 
fossa.  This  closure  proceeds  usually  from,  two  points,  the  internal  ring 
and  just  above  the  epididymis,  commencing,  as  a  rule,  at  the  former 
point  Part  of  the  pouch  between  these  two  points  may  remain  open  and 
giye  rise  to  an  "encysted  hydrocele  of  the  cord,"  if  fluid  collects  in  it. 

1.  Sometimes  the  vaginal  process  does  not  close,  but  remains  continuous 
with  the  peritoneal  cavity.  A  hernia  may  descend  into  this  process  as  a 
sac  which  is  preformed  or  congenital.  Hence  this  variety  is  known  as 
congenital  inguinal  hernia.  Such  a  hernia  need  not  occur  at  once  or  even 
shortly  after  birth,  though  it  is  very  common  at  this  period.  It  often 
develops  after  some  years,  in  which  case  the  upper  opening  of  the  process, 
remaining  constricted  or  closed  by  a  thin  septum,  is  dilated  or  torn  by 


Diagrammatic   representation  of  the  varieties  of  external   inguinal   hernia  due  to  congenital 
defects  in  the  vaginal  process:     1,  the  processus  vaginalis,  showing  the  two  points  where  closure 

of  the  upper  part  commences,  at  C  and  C;  2,  congenital  hernia;  3,  hemia  into  the  funicular 
process;  i,  infantile  hernia;  5,  acquired  hernia;  E,  external  abdominal  ring;  /,  internal  abdom- 
inal ring;    /'.,S'.,  peritoneal  sac;    li,  herniated  bowel;    /'./•'.,  funicular  process;    7',  testis. 

the  hernia  U>vcc(\  through  it  by  some  sudden  strain.  It  may  also  occur 
when  the  testis  has  not  descended,  provided  the  processus  vaginalis  has 
passed  into  the  scrotum,    The  presence  of  a  congenital  sac  by  no  means 

necessitates  the  occurrence  of  ;i  hernia.     Ill  congenital  hernia'  the  80C  is 

very  thin,  the  neck  long  and  narrow,  and  the  parts  aboui  it  have  been 
little  disturbed  or  distended,  so  that  strangulation  is  relatively  more 
frequent  ami  seven-  in  this  variety  than  in  the  acquired  form.  Reduction 
by  taxis  may  be  difficult  by  reason  of  ii    lung  narrow  neck.    Iii  the  attempt 

at  taxis  pressure  hould  be  made  upward  then  upward  and  outward,  in 
the  course  of  the  canal,  ami   then  backward.      As  the  natural   tendency 

of  ;i  congenital  lac  is  to  close  during  early  life,  especially  as  the  canal 
grows  longer  and  more  oblique,  we  can  often  effect  b  tun  in  children  l>\ 
Keeping  the  contents  permanently  reduced. 

_'.   The    upper  end    of   the    vaginal    process    may   dose    while    the    rest 
remains  '.pen,  ;i   condition   which  is  the  rule  in  «.mI\   infancy.      If  miller 


296  THE  ABDOMEN 

such  circumstances  a  hernia  with  its  peritoneal  sac  is  forced  down,  or, 
according  to  Lockwood's  theory,  a  peritoneal  sac  is  drawn  down  by  the 
gubernaculum,  such  a  hernia  is  called  an  infantile  inguinal  hernia,  for  it 
was  first  described  in  infants. 

As  the  sac  lies  behind  the  open  vaginal  process  we  must  pass  through 
this  process  to  open  the  sac,  and  in  so  doing  we  would  divide  three  layers 
of  'peritoneum,  two  of  the  process  and  one  of  the  sac.  The  variety  is 
uncommon  and  unimportant.  The  hernial  sac  may  occasionally  project 
into  or  invaginate  the  vaginal  process,  giving  rise  to  the  term  encysted 
hernia. 

3.  Again,  the  closure  of  the  vaginal  process  may  occur  only  below, 
just  above  the  testis,  and  a  hernia  into  this  preformed  sac  is  known  as  a 
hernia  into  the  funicular  process. 

This  sac  is  congenital,  and  it  differs  from  the  so-called  congenital 
hernia  only  in  the  fact  that  in  the  latter  the  contents  are  in  contact  with 
the  testicle,  in  the  former  they  are  separated  by  the  septum,  which  has 
shut  off  the  tunica  vaginalis  testis.  Herniae  which  become  fully  formed 
in  a  short  time  are  of  congenital  origin.  It  is  probable  that  in  a  majority 
of  cases  the  sac  of  a  hernia  is  of  congenital  origin. 

4.  Finally,  those  hernia?  whose  sac  is  formed  anew  from  the  peritoneum 
of  the  external  fossa  are  known  as  acquired  external  inguinal  hernise. 
This  variety  develops  more  slowly  and  does  not  descend  as  low  in  the 
scrotum  or  come  in  such  close  contact  with  the  testis  as  the  congenital 
varieties. 

Internal  or  Direct  Inguinal  Hernia. — Internal  or  direct  inguinal  hernia 
is  one  which  emerges  internal  to  the  deep  epigastric  vessels  and,  as  its 
name  implies,  passes  directly  forward  through  the  abdominal  wall  where 
it  appears  to  be  weakest.  Nevertheless,  it  is  far  less  common  than  the 
indirect  form,  a  fact  due  to  congenital  conditions,  the  presence  of  the  cord 
in  the  canal  and  the  funnel-shaped  depression  of  peritoneum  at  the  inter- 
nal ring  which  act  as  predisposing  causes  of  the  indirect  variety.  Direct 
hernia  occurs  most  often  when  the  abdominal  walls  have  lost  their  strength 
and  are  lax,  as  in  old  age,  after  any  prolonged  distention,  or  after  emacia- 
tion following  obesity.  Its  point  of  exit  is  usually  in  the  middle  inguinal 
fossa,  opposite  the  external  ring,  rarely  in  the  internal  fossa,  in  which  case 
it  has  been  called  "internal  oblique  hernia,"  as  its  course  is  somewhat 
obliquely  outward  to  emerge  at  the  external  ring.  The  neck  of  a  direct 
hernia  is  usually  wide,  admitting  one  or  two  fingers,  but  the  pulsation  of 
the  deep  epigastric  artery  can  rarely  be  felt  to  its  outer  side.  Strangula- 
tion is  not  common,  occurring  most  often  at  the  external  ring.  Its  cover- 
ings differ  only  normally  from  those  of  the  external  variety.  Trans- 
versalis  fascia  takes  the  place  of  that  local  subdivision  of  it,  the 
infundibuliform  fascia.  In  place  of  the  cremasteric  fascia  we  have  the 
conjoined  tendon,  except  in  certain  cases  where  the  hernia  escapes  beneath 
it  or  breaks  through  between  its  fibers  without  receiving  a  covering.  If 
it  escapes  through  the  inner  fossa,  the  triangular  fascia  may  form  one  of 
its  coverings. 

Other  features  of  this  form  of  hernia  may  be  best  brought  out  by 


THE  ANTERIOR  ABDOMINAL   WALL  297 

observing  the  differences  between   an  internal  and  an  external  inguinal 
hernia. 

The  shape  of  an  internal  inguinal  hernia  is  globular  on  account  of  its 
short  neck,  that  of  an  external  is  pear-shaped. 

The  size  of  the  former  is  smaller,  and  it  has  little  tendency  like  the 
latter  to  follow  the  cord  or  descend  low  into  the  scrotum.  The  position 
of  the  former  is  more  internal,  and  it  lies  more  internal  to  and  in  front  of 
the  cord  instead  of  in  front  of  and  external  to  it.  On  reduction  the  track 
of  the  neck  of  the  internal  is  short  and  straight,  that  of  the  external  is 
oblique  and  longer.  Also  if  the  finger  can  be  introduced  through  their 
deep  openings,  the  pulsations  of  the  deep  epigastric  artery  may  possibly 
though  rarely  be  felt  internally  in  external  hernia  and  externally  in 
internal  hernia;  while  internally  in  the  latter  may  be  felt  the  edge  of  the 
rectus  muscle. 

The  external  form  is  often  congenital,  the  internal  never.  The  external 
form  occurs  especially  in  early  life,  the  internal  late  in  life. 

From  these  differences  it  would  seem  an  easy  matter  to  distinguish 
between  the  two  forms,  and  so  it  is  where  the  relations  of  the  various 
parts  are  not  much  disturbed,  as  in  recent  or  congenital  hernise.  But 
in  old  external  inguinal  hernia  the  traction  of  an  increasing  weight 
on  the  inner  side  of  the  internal  ring  enlarges  it  on  this  side,  brings  it 
nearer  or  even  opposite  the  external  ring,  and  so  shortens  the  canal  and 
makes  it  less  oblique.  Also,  if  the  rupture  is  irreducible,  some  of  the 
diagnostic  points  will  be  wanting.  Thus,  it  may  be  difficult  or  impos- 
sible to  distinguish  between  the  two  varieties. 

Hernia  Operations. — The  incision  is  made  over  the  course  of  the 
canal,  but  somewhat  more  vertically,  and  extends  for  a  short  distance 
beyond  it.  It  is  laid  out  according  to  the  landmarks  we  have  given 
for  the  canal.  The  superficial  external  pudic  artery  is  usually  divided, 
but  is  of  no  importance.  Several  large  veins,  varying  in  size  and  number, 
may  be  met  with  crossing  the  line  of  incision.  In  recent  or  small  external 
hernise  the  point  of  constriction,  if  strangulation  occurs,  may  be  at  the 
internal  or  external  ring,  but  it  is  more  often  in  the  narrow  neck  of  the 
sac  itself,  which  must  then  be  opened. 

In  the  operation  most  often  practised,  that  of  Bassini,  the  dilated  or 
enlarged  canal  is  obliterated,  so  as  not  to  leave  an  easy  passageway  for 
the  recurrence  of  th<'  hernia,  and  a  new  (rack  is  made  for  the  cord. 

How  Are  We  to  Recognize  the  Different  Layers? — It  is  neither  neces- 
Qor  always  possible  to  distinguish  all  of  diem.  After  division  of  the 
skin  whatever  moves  with  the  cut  edges  belongs  t<>  the  superficial  fascia, 
unless  inflammation  has  rendered  the  latter  adherent  to  the  parts  beneath. 
Tin-  external  oblique  aponeurosis  can  easily  be  told  by  its  pearly  shining 
oblique  fibers.  The  cremaster,  or  conjoined  tendon,  is  the  only  muscle 
n nially  expo  ed,  and  may  !><•  recognized  by  the  attachment  and  direction 
of  its  fibers.  Some  difficulty  may  be  found  in  determining  whether  the 
peritoneal  lac  has  l><-«-n  opened  or  not. 

In  congenital  inguinal  hernia'  the  sac  h  more  closelj  adherent  to  the 
fa  rial  layer  outside.    This  may  enable  us  to  know  when  we  meet  with 


298  THE  ABDOMEN 

such  a  hernia,  but  it  makes  it  more  difficult  to  free  the  sac  as  well  as  to 
know  when  we  have  opened  it. 

How  are  we  to  distinguish  between  the  sac  and  the  intestinal  wall? 

1.  The  outside  of  the  sac  has  not  a  shiny  smooth  surface,  like  that  of 
the  peritoneal  surface  of  the  intestine,  but  often  shows  attached  to  it 
little  lumps  of  fat  and  shreds  of  areolar  tissue  belonging  to  the  sub- 
peritoneal tissue. 

2.  The  vessels  on  the  sac  run  more  vertically,  those  on  the  intestine 
circularly. 

3.  If  we  pinch  up  a  fold  between  the  fingers  the  sac  is  very  thin,  the 
intestinal  wall  thicker.  The  presence  of  fluid  within  the  sac,  in  large 
amount  in  strangulated  hernia,  is  also  of  great  diagnostic  importance. 

In  what  direction  should  we  not  incise  to  relieve  a  constriction  of  the 
neck  of  an  inguinal  hernia?  In  the  external  form,  not  backward  on 
account  of  the  cord,  nor  inward  on  account  of  the  deep  epigastric  artery. 
In  the  internal  form,  not  backward  on  account  of  the  vas  deferens  and 
bloodvessels,  nor  outward  for  fear  of  the  deep  epigastric  artery.  But 
as  it  is  often  impossible  to  distinguish  between  the  two  forms  it  is  advis- 
able in  any  case  to  incise  as  if  it  might  be  either  variety,  and  not  to  cut 
backward,  inward,  or  outward. 

Hence  we  should  incise  upward  or  upward  and  slightly  inward,  i.  e., 
parallel  with  the  deep  epigastric  artery.  An  extensive  cut  is  unnecessary, 
several  small  cuts  answer  equally  well.  Incision  of  the  neck  of  the  sac 
is  only  called  for  in  cases  of  strangulated  hernia,  and  with  care  may  be 
done  from  without  as  well  as  from  within  the  sac.  In  fact,  the  former  is 
now  preferable,  as  the  radical  operation  is  almost  always  done  in  such 
cases. 

Strangulation  consists  in  the  obstruction  of  the  blood  supply  by 
the  constriction.  At  first  the  venous  circulation  alone  is  obstructed. 
This  causes  swelling  and  increases  the  constriction  and  the  arterial  cir- 
culation becomes  arrested.  Paralysis  of  the  intestines  develops,  which 
completes  the  existing  obstruction  to  the  passage  of  intestinal  contents. 
Gangrene  and  perforation  of  the  gut  follow  if  the  constriction  is  not 
relieved. 

The  nerves  of  and  about  the  inguinal  canal  are  important  in  con- 
nection with  operations  under  local  anesthesia.  The  line  of  incision 
involves  the  cutaneous  distribution  of  the  twelfth  thoracic  and  iliohypo- 
gastric nerves.  The  latter  emerges  through  the  aponeurosis  3  to  5  cm. 
(lj  to  2  in.)  above  the  external  ring  and  supplies  the  skin  near  the  inner 
end  of  the  incision. 

The  ilio-inguinal  nerve  and  the  genital  branch  of  the  genitocrural 
nerve  are  generally  found  anastomosed  in  the  canal,  where  they  are 
seen  in  front  of  the  cord  or  hernial  sac  on  splitting  up  the  aponeurosis. 
The  cocainization  of  this  common  trunk  at  the  outer  end  of  the  canal, 
or  beyond,  anesthetizes  the  entire  scrotal  contents,  including  the  cord, 
hernial  sac,  and  testis.  There  is  no  anesthesia  of  the  scrotum,  though 
it  is  generally  stated  that  these  nerves  furnish  a  cutaneous  supply  to 
the  scrotum.      Division   of    this   nerve   trunk    should    be    avoided    in 


THE  ANTERIOR  ABDOMINAL   WALL 


299 


herniotomy,  for  it   results  in    paralysis  of   the   cremaster   muscle  (see 
Fig.  103).' 

The  Length  of  the  Mesentery  in  its  Relation  to  the  Formation  of  a 
Hernia. — Mr.  Loekwood  has  shown:  (1)  That  with  a  mesentery  of 
normal  length  the  intestine  may  be  drawn  down  through  the  external 


Fig.  L03 


— V-  Lateral  Cutan's  of  12  D 


Anterior  Cutan' 


Anterior  Cutan'*  of  1  L.    / 
Hlio-hypo.)  / 

Int  Ring-—' 


Sueemci*  perineal   I 

of  Pudicx3-4  S. 


foguinoeeroteJ  nervea,  their  peripheral  distribution  and  relation  of  main  tnmka  to  hernia 
incision:  ',  iliohypogastric;  It,  flio-inguinal;  ///.  genitoorural;  IV,  genital  branoh;  V,  orural 
branch.      II"-  heavy  line  represent*  the  111 f  Incision. 

Hug  l)ut  aol  into  the  scrotum  '  Thai  the  mesentery  is  relatively 
longer  in  infancy,  decrea  ing  rapidly  in  the  second  year,  and  averaging 
20  cm  in  length  in  theaault.    In  the  congenital  hernia  of  infancy 

the  in.  .,,1.  i .  may  allow  the  gul  to  descend  into  the  scrotum  withoul 
becoming  lengthened,  b    i    oece   arj  in  adult  , 


300  THE  ABDOMEN 

Interparietal  Inguinal  Hernia. — An  interparietal  inguinal  hernia 
is  one  in  which  the  sac  or  a  diverticulum  from  it  insinuates  itself 
between  the  layers  of  the  abdominal  wall.  It  usually  starts  as  an 
external  hernia,  but  owing  to  some  obstacle  to  the  usual  course  it  ex- 
tends in  the  line  of  least  resistance  and  makes  its  way  between  some 
of  the  layers  of  the  abdominal  wall,  i.  e.,  between  the  peritoneum  and 
the  transversalis  fascia  (properitoneal  hernia),  between  the  transversalis 
fascia  and  muscle,  between  the  internal  and  external  oblique,  or  super- 
ficial to  the  latter.  This  form  of  hernia  is  most  apt  to  occur  when,  for 
some  reason,  the  external  ring  is  narrower  than  normal  or  is  closed. 
These  conditions  are  present  when  the  testicle  has  not  completely 
descended,  but  is  lodged  just  above  or  within  the  inguinal  canal.  The 
latter  position  of  the  testis  especially  favors  the  production  of  such  a 
hernia,  for  the  upper  end  of  the  canal  is  enlarged  and  commonly 
occupied  by  a  pouch  of  peritoneum. 

In  such  a  hernia  the  tumor  is  flattened  out.  According  to  Tillaux, 
strangulation  may  occur  by  compression  of  the  surrounding  muscular 
layers,  and  taxis  is  more  harmful  than  useful. 

Reduction  en  Masse. — A  hernia  may  be  reduced  by  taxis  together 
with  its  sac  so  that  any  constriction  in  the  neck  of  the  sac  still  exists. 
In  such  cases  the  sac  may  be  pushed  up  between  the  peritoneum  and 
the  abdominal  walls,  or,  if  the  infundibuliform  covering  is  ruptured, 
in  front  of  or  behind  the  conjoined  tendon  which  forms  the  upper  boun- 
dary of  the  canal.  It  is  not  unlikely  that  some  if  not  most  of  the  cases 
in  this  group  are  really  interstitial  hernise  in  which  only  the  lower  part 
of  the  hernia  has  been  reduced. 

Inguinal  Hernia  in  the  Female. — A  pouch  of  peritoneum,  the  canal 
of  Nuck,  corresponding  to  the  vaginal  process  in  the  male,  descends  in 
fetal  life  for  some  distance  along  the  round  ligament,  and  when,  as  some- 
times happens,  it  remains  open  it  may  form  the  sac  of  a  congenital  hernia. 

Inguinal  hernia  in  the  female  is  most  common  in  infancy,  early  childhood, 
or  after  the  first  pregnancy.  In  the  former  case  it  is  congenital,  in  the 
latter  acquired,  the  canal  having  become  distended  during  pregnancy, 
by  the  enlargement  of  the  cord,  which  shrinks  after  childbirth  and 
leaves  the  canal  more  lax.  The  round  ligament  bears  the  same  relation 
to  the  hernial  sac  as  does  the  cord  in  the  male. 

After  emerging  at  the  external  ring  a  hernia  may  pass  down  into  the 
labium  majus.  The  coverings  are  the  same  as  in  the  male  except  that 
the  cremasteric  layer  is  usually  wanting,  for  the  hernia  commonly  passes 
beneath  the  conjoined  tendon.  The  contents  are  also  the  same  except 
that  the  ovary  or  even  the  uterus,  in  part,  may  be  found  in  the  sac. 
Internal  inguinal  hernia  is  very  rare  in  women. 

Operations. — Operations  in  this  region,  except  for  hernia,  are  chiefly 
those  to  shorten  the  round  ligaments,  to  open  abscesses,  or  to  tie  the 
external  iliac  artery.  To  shorten  the  round  ligament  the  incision  is  made 
as  for  hernia.  The  external  ring  is  exposed,  the  tissue  lying  just  internal 
to  it  is  hooked  up  with  a  blunt  hook,  and  the  round  ligament  is  sought 
for  in  this  tissue,    If  the  ligament  cannot  be  so  found,  the  canal  should 


THE  ANTERIOR  ABDOMINAL   WALL 


501 


be  slit  up  and  its  contents  caught  up  on  the  hook.  After  pulling  the  liga- 
ment down  for  a  certain  distance  it  becomes  more  fleshy  and  thick  and  a 
double  sheath  of  peritoneum  is  drawn  down  with  it,  which  may  predispose 
to  subsequent  hernia. 

Abscesses  are  principally  of  two  varieties,  to  be  spoken  of  in  the  study 
of  the  iliac  fossa.  One  variety  is  in  the  subperitoneal  tissue  of  the  iliac 
fossa  and  is  limited  infer iorly  by  the  line  of  Poupart's  ligament.  Here 
it  raises  up  the  peritoneum  and  may  be  incised,  just  above  Poupart's 
ligament,  without  opening  the  peritoneum.  The  other,  psoas  abscess, 
is  beneath  the  iliac  fascia  and  may  point  above  or  below  the  middle  or 
outer  half  of  Poupart's  ligament.    When  above  the  ligament  it  may  be 


Fig.  mi 


UPART'S 
LIGAMENT 


MUSCULAR 
LACUNA 


ILIO-PECTIN- 
EAL   LIGAMENT 


ILIO-PECTIN- 
EAL   EMINENCE 


VASCULAR 
LACUNA 


COOPER'S 
LIGAMENT 

-GIMBERNAT'S 
LIGAMENT 


SPERMATIC 
CORD 


i  ligament.     (Joenel.) 

exposed  and  opened  after  incising  the  transversalis  fascia  and  pushing 
up  the  lower  limit  of  the  peritoneum,  thus  bringing  to  riew  the  iliac 

fa  cia. 

We  proceed  to  a  similar  waj  to  expose  the  external  iliac  artery,  for 
which  see  [liac  Region,  p.  309. 

The  Inguinofemoral  Region  and  Femoral  Hernia.  This  region  is 
tfae  passageway  between  the  upper  pari  of  the  thigh  and  the  region  above. 
Poupart's  ligament  brid  the  concave  iliopubic  margin  of  the  hip 

bone  ;m,|  thereby  form   a   pace,  mainly  occupied  bv  the  iliopsoa    tnu  cle 
and  the  external  ili  ing  into  the  thigh.   The  fascia  inve  I 

ing  these    tructurea    ubdivides  the  -parr  into  compartments  or  lacunae. 


302  THE  ABDOMEN 

The  largest  and  most  external  of  these  is  the  muscular  compartment 
occupied  by  the  iliopsoas  muscle  and  the  anterior  crural  and  external 
cutaneous  nerves.  It  is  bounded  externally  and  behind  by  the  bony 
iliac  margin  between  the  anterior  superior  spine  and  the  iliopectineal 
eminence;  in  front  by  Poupart's  ligament  and  the  iliac  fascia,  and  inter- 
nally by  the  iliac  fascia  (iliopectineal  septum  or  ligament).  The  iliac 
fascia  is  firmly  attached  to  the  transversalis  fascia  and  Poupart's  liga- 
ment along  the  outer  4  cm.  (1J  in.)  of  the  latter,  but  then  separates 
from  them  to  pass  to  the  iliopectineal  eminence,  where  it  is  continuous 
with  the  pectineal  fascia,  i.  e.,  the  pubic  portion  of  the  fascia  lata.  It 
is  in  this  compartment  that  a  psoas  abscess  passes  beneath  Poupart's 
ligament  to  "point"  below  it. 

The  pectineus  muscle  passes  up  a  short  distance  above  Poupart's 
ligament  and  may  be  said  to  occupy  a  pectineal  compartment,  limited 
behind  by  the  horizontal  pubic  ramus  and  in  front  by  the  pectineal 
fascia.  The  upper  limit  of  this  fascia,  along  the  iliopectineal  line,  is 
thickened  by  transverse  fibers  from  Gimbernat's  ligament. 

The  rest  of  the  space  is  triangular  in  shape  and,  save  the  inner  angle 
occupied  by  Gimbernat's  ligament,  constitutes  the  vascular  compart- 
ment. 

This  is  bounded  in  front  by  Poupart's  ligament  (i.  e.,  the  superficial 
femoral  arch)  and  the  transversalis  fascia,  which  is  attached  to  Poupart's 
ligament,  and  is  thickened  by  transverse  fibers  and  known  as  the  deep 
femoral  arch.  Behind  the  compartment  are  the  iliac  and  pectineal 
fasciae,  continuous  with  one  another.  The  external  iliac  vessels  and  the 
crural  branch  of  the  genitocrural  nerve  occupy  this  compartment  in  their 
passage  into  the  thigh,  the  vein  lying  internal  to  the  artery. 

The  vessels  do  not  occupy  the  entire  compartment,  but  there  is  an 
interval  of  15  to  25  mm.  (-§  to  1  in.)  between  the  vein  and  the  outer 
margin  of  Gimbernat's  ligament,  which  constitutes  the  femoral  ring, 
through  which  a  femoral  hernia  forces  its  way  beneath  Poupart's 
ligament. 

In  passing  beneath  Poupart's  ligament  into  the  thigh  to  become  the 
femoral  vessels  the  external  iliac  vessels  carry  with  them  a  fascial  sheath, 
the  femoral  sheath,  which  bounds  the  vascular  compartment  and  is 
continuous  with  the  fascia  lining  the  abdomen,  i.  e.,  the  transversalis 
fascia  in  front  and  the  iliac  fascia  behind.  These  fasciae  are  continuous 
with  one  another  internally  and  externally  so  as  to  form  a  complete  sheath. 
This  sheath  is  funnel-shaped,  wide  above  but  closely  embracing  the  vessels 
below,  where  it  is  continuous  with  their  proper  sheath.  The  width  of  the 
sheath  beneath  Poupart's  ligament  prevents  compression  of  the  vein  and 
pinching  or  stretching  of  the  vessels  in  movements  at  the  hip. 

The  vessels  occupy  the  outer  side  of  the  funnel  and  leave  a  pyramidal 
space,  the  femoral  canal,  on  the  inner  side  of  the  vein  and  separated  from 
it  by  connective  tissue,  belonging  to  the  flbrocellular  or  proper  sheath  of 
the  vessels.  This  canal  measures  12  to  18  mm.  (-J  to  |  in.)  in  length, 
and  tapers  to  its  lower  closed  end,  which  is  about  opposite  the  upper  end 
of  the  saphenous  opening.    It  is  only  a  potential  canal,  like  the  inguinal, 


THE  ANTERIOR  ABDOMINAL   WALL  303 

not  a  real  one  unless  made  so  by  a  hernia  or  the  knife.     It  represents  a 
weak  spot  which  forms  the  passageway  of  a  femoral  hernia. 

The  femoral  canal  is  bounded  externally  by  the  femoral  vein  with  a 
septum  of  connective  tissue  between,  and  on  the  other  sides  by  the  fem- 
oral sheath.  It  contains  fatty  and  cellular  tissue,  lymphatics  which 
penetrate  its  anterior  wall  and  pass  from  the  superficial  to  the  deep 
inguinal  nodes,  and  one  or  more  lymph  nodes.  Its  upper  or  abdominal 
aperture  is  the  transversely  oval  femoral  ring,  mentioned  above.  The 
size  of  the  ring  varies,  but  is  usually  sufficient  to  admit  the  tip  of  the  fore- 
finger.    It  averages  15  mm.  (|  in.)  in  diameter  in  the  male,  and  is  half 


1 1...  in.-. 


ANT. -SUP. 
ILIAC    SPINE 


ion   <>f  tin-  crural   canal   and   "f   the   tnL%BCul.ii    ami    paeoular  compartment!  beneath 
Poupart'a  ligament       I  I  tltaux.) 

again  as  large  in  the  female,  hence  tin1  greater  frequency  of  femoral 
hernia  in  women  in  die  ratio  of  three  to  our.  [ts  greater  width  in  women 
ia  not  due  to  any  greater  width  of  tli<'  space  beneath  Poupart'a  ligament, 
for  (Iih  is  not  wider,  bul  i<>  the  smaller  size  of  the  muscles,  occupying  the 
muscular  compartment,  and  of  <  rimbernat's  ligament. 

When  viewed  from  above  the  femoral  ring  is  seen  to  be  covered  l>\ 
peritoneum,  which  may  present  a  slight  depression,  the  fossa  femoralis. 
According  to  Tillaux,  such  a  depre  i<»n  i.  no1  normal  bul  pathological, 
the  peritoneum  being  drawn  down  l>\  an  attached  fal  lobule  belonging 
to  the  subperitoneal  tissue,  which  i>  frequently  the  site  of  subserous 
lipomata. 


304  THE  ABDOMEN 

On  removing  the  peritoneum  the  ring  is  seen  to  be  closed  by  the  septum 
crurale  (Cloquet),  a  condensed  layer  of  connective  tissue,  continuous  with 
the  subperitoneal  tissue  and  perforated  by  lymphatics  passing  from  the 
inguinal  to  the  iliac  nodes.  A  small  lymph  node  is  sometimes  found 
lying  on  it.  Inflammation  of  this  gland  or  of  one  in  the  canal  has  been 
mistaken  for  strangulated  hernia,  on  account  of  a  similarity  of  symp- 
toms. 

The  boundaries  of  the  ring  are  of  great  practical  importance  from 
their  relation  to  the  neck  of  a  femoral  hernia.  To  the  outer  side  lies 
the  vein  in  its  sheath,  elsewhere  the  boundaries  are  of  firm  fibrous  struc- 
tures. In  front  lies  the  superficial  femoral  arch  (Poupart's  ligament) 
and  the  deep  femoral  arch  (see  p.  302).  Behind  is  the  thin  upper  end  of 
the  pectineus  muscle,  resting  on  the  horizontal  pubic  ramus  and  covered 
by  the  thickened  upper  end  of  the  pectineal  fascia.  Internally  there  is 
a  series  of  firm  fibrous  structures,  attached  to  the  iliopectineal  line,  as 
follows  from  below  upward:  the  iliac  portion  of  the  fascia  lata,  Gim- 
bernat's  ligament,  the  triangular  fascia,  the  conjoined  tendon,  and  the 
deep  femoral  arch.  These  structures  present  a  sharp  free  margin  toward 
the  ring. 

Relation  of  Parts  about  the  Ring. — The  spermatic  cord  in  the  male 
and  the  round  ligament  in  the  female  lie  in  loose  tissue  5  to  6  mm.  (^  to 
\  in.)  above  the  anterior  margin  of  the  ring.  The  deep  epigastric  vessels 
lie  above  and  to  its  outer  side,  between  the  internal  abdominal  and  the 
femoral  rings,  distant  about  12  mm.  Q-  in.)  from  the  latter.  The  small 
pubic  branch  of  this  artery  runs  across  in  front  of  the  ring,  to  ramify 
on  the  upper  aspect  of  Gimbernat's  ligament  and  of  the  os  pubis. 
These  structures  are  in  danger  of  being  divided  by  a  free  incision 
upward,  but,  according  to  Tillaux,  not  by  an  incision  or  incisions  of 
5  mm.  (y  in.),  which  may  subsequently  be  enlarged  by  the  finger. 

The  internal  and  posterior  aspect  of  the  ring  are  usually  free  from 
important  relations.  Therefore,  to  relieve  the  constriction  in  a  strangu- 
lated hernia  we  may  incise  backward,  but  little  room  is  to  be  gained  here, 
as  only  a  thin  layer  of  soft  parts  covers  the  bone.  Hence  we  incise 
inward,  bearing  in  mind  the  following  variations. 

Once  in  every  three  and  one-half  cases  the  obturator  artery  is  given  off 
as  a  branch  of  the  deep  epigastric  artery.  The  course  of  this  branch  is 
commonly  to  the  outer  side  of  the  ring,  where  it  lies  close  to  the  vein,  and 
not  exposed  to  injury  by  incision,  for  we  never  incise  outward  on  account 
of  the  vein.  Occasionally  (in  1  to  3^  per  cent.)  the  common  trunk  is 
longer,  crossing  in  front  of  the  ring,  and  the  obturator  branch,  with  its 
vein,  passes  back  close  to  the  inner  border  of  the  ring  where  artery  and 
vein  are  exposed  to  injury  by  a  free  incision  inward.  Cases  are  recorded 
where  such  an  injury  has  resulted  fatally,  and  the  reason  why  it  does 
not  occur  more  frequently  seems  to  be  that  the  vessels  lie  in  loose 
tissue,  2  to  5  mm.  from  the  edge  of  the  ring,  and  may  be  readily 
pushed  back  before  the  knife,  and  also  that  multiple  short  incisions 
are  often  employed. 

If  the  finger  can  be  pushed  through  the  ring  the  pulsation  of  such  an 


PLATE  XXXI 


FIG.   106 


SAC    OF    FEMORAL 
HERN 


DEEP    EPIGAST. 


INTERNAL 

ABOOM.  > 

Rl  NG 


GIMBER- 
NAT'S 
LIG. 
ABNOR. 
ORIGINS 
OF    OB- 
TURATOR 
ARTERY 


OBTURATOR 
NERVE 


POUPART'S 
LIGAMENT 


XT.    ILIAC 
ESSELS 


VAS    DEFERENS 


VES.    SEMINAL 


Rear    View    of    Anterior    Abdominal    Wall,    Showing     Right 
Inguinal   and   Left   Femoral   Hernia.    (Joessel.) 

The  obturator  artery  i-  given  "IT  by  the  epigastric,  the  "lotted  line  <>n  the  lefl  showing 
another,  rarer  :m<l  mure  important,  Form  <>r  \\ii>  variety. 


THE  AXTERIOR  ABDOMINAL  WALL  305 

aberrant  artery,  lying  internally,  may  perhaps  be  felt.  It  should  be 
sought  for  so  as  to  avoid  the  chance  of  an  accident. 

The  size  and  the  tension  of  the  femoral  ring  and  canal  and  of  the 
saphenous  opening,  and  hence  the  constriction  of  a  hernia  passing 
through  them,  varies  with  the  position  of  the  limb.  They  are  enlarged 
and  relaxed  in  flexion,  adduction,  and  inward  rotation  of  the  thigh,  and 
hence  taxis  should  be  tried  in  this  position.  In  the  reverse  position  these 
parts  are  rendered  tense  by  the  tension  of  the  fascia  lata  and  its  traction 
upon  Poupart's  ligament. 

Femoral  Hernia. — Femoral  hernia  is  always  acquired,nevei  congenital. 
It  occurs  almost  exclusively  in  adult  life.  Though  more  common  in 
women  than  in  men  in  the  ratio  of  3  to  1,  it  is  less  common  in  women  than 
the  inguinal  variety,  contrary  to  the  general  impression.  The  weakening 
effect  of  pregnancy  on  the  abdominal  walls  increases  the  liability  of 
women  to  femoral  hernia,  so  that  it  is  more  common  after  the  first 
pregnancy. 

Course  and  Coverings. — A  pouch  is  gradually  formed  of  the  peritoneum 
covering  the  weak  spot,  the  femoral  ring.  This  forms  the  hernial  sac 
and  a  covering  is  received  from  the  septum  crurale  in  passing  through 
the  ring  beneath  Poupart's  ligament.  The  hernia  descends  vertically 
in  the  femoral  canal  to  its  lower  end,  opposite  the  saphenous  opening. 
Here,  taking  the  direction  of  least  resistance,  it  turns  forward  and  finally 
upward  or  upward  and  outward  toward  the  anterior  superior  iliac  spine, 
even  as  far  as  Poupart's  ligament,  receiving  coverings  from  the  femoral 
sheath  and  the  cribriform  fascia.  It  thus  comes  to  lie  beneath  the  skin 
and  subcutaneous  tissue. 

Various  reasons  have  been  adduced  to  explain  the  curved  course  of 
the  hernia:  (1)  The  canal  curves  slightly  with  the  concavity  forward. 
2)  The  downward  course  is  limited  by  the  lower  limit  of  the  canal 
and  the  firmness  of  the  lower  margin  of  the  saphenous  opening  which 
i-  closely  united  with  the  femoral  sheath  and  the  cribriform  fascia.  (3) 
Tli<-  constant  flexion  of  the  thigh.  (4)  The  loops  formed  by  the  vessels 
passing  to  the  saphenous  opening  prevent  the  further  descent  of  a 
hernia.     5)  Thetraction  of  the  mesentery. 

The  course  of  a  hernia  should  be  borne  in  mind  in  applying  taxis  in 
the  reverse  direction  for  it  i  reduction. 

From  the  above  we  may  summarize  the  coverings  from  without  as 
follows:   (1)    skin;   (2)    subcutaneous    tissue;   (3)    cribriform    fascia;    (I) 

anterior  wall  of  the  femoral  canal  (femoral  sheath);  (.r>)  septum  crurale; 
(6)  peritoneal 

The  80C  of  mil  a  hernia  comes  to  lie  very  close  beneath  the  skin. 
One  or  more  of  Nos.  •'>,  I-  mid  5  may  be  broken  through  instead  of  pushed 
I. cfoie  tin-  hernia  90  ;i^  to  be  wanting  as  :i  covering,  ami  the  lorn  opening 
of  such    layer  Or   layers    may   be    the   scat   of  constriction .      \os.     1    and    5 

or  :;,  I, and  5),  often  matted  together  mid  combined  to  form  a  single 
covering,  were  called  fascia  propria  by  Sir  A.  Cooper.  It  is  often  impos- 
sible to  <li  tinguish  the  separate  layers  as  they  may  be  thinned  out  and 
adherent  to  one  another.    In  cfi  ie  of  a  hernia  confined  t<>  the  upper  pari 

20 


306  THE  ABDOMEN 

of  the  canal,  the  iliac  portion  of  the  fascia  lata  forms  a  covering  between 
the  femoral  sheath  and  the  superficial  fascia  in  the  place  of  No.  3. 

A  hernia  confined  to  the  canal  is  small,  owing  to  the  unyielding 
character  of  its  fibrous  walls,  and  is  generally  readily  reducible,  as  the 
neck  is  as  large  as  the  rest  of  the  hernia.  After  protruding  at  the  saphe- 
nous opening  into  the  loose  subcutaneous  tissue  of  the  groin  a  femoral 
hernia  is  apt  to  be  small  and  globular,  but  may  attain  considerable  size. 

The  contents  are  not  characteristic;  omentum  is  very  often  present 
and  apt  to  be  adherent;  intestine  is  less  often  present  than  in  inguinal 
hernia,  but  is  more  likely  to  be  strangulated.  In  the  latter  case  the  seat 
of  the  constriction  is  usually  at  the  inner  margin  of  the  femoral  ring  or 
at  the  margin  of  the  saphenous  opening. 

Herniotomy. — The  incision  may  be  parallel  to  Poupart's  ligament  and 
over  the  tumor,  or  vertical  and  on  its  inner  side.  Poupart's  ligament 
should  be  exposed  as  a  landmark.  In  large  hernise  the  overlying  layers 
may  be  few  in  number  or  much  thinned  out,  so  the  incision  should  be 
made  with  care.  The  amount  of  subperitoneal  fat  is  sometimes  very 
great,  so  as  to  simulate  omentum,  while  the  thinned  fascia  propria  may  be 
mistaken  for  the  sac.  In  such  a  case,  after  enlarging  the  ring,  the  real 
sac  embedded  in  fat  may  be  reduced  with  its  contents,  and,  if  the  con- 
striction be.in  the  neck  of  the  sac,  the  strangulation  would  not  be  relieved. 
This  fat  is  so  abundant  that,  in  a  tumor  of  some  size,  it  is  not  always 
easy  to  find  the  small  sac.  We  incise  the  constriction  inward,  inward  and 
backward,  or  inward  and  forward  (Cooper).  The  small  external  pudic 
vessels  lie  behind  the  hernia,  and  therefore  are  not  cut  by  the  incision. 

In  Bassini's  radical  operation,  after  removing  the  sac  high  up,  the 
canal  is  closed  by  suturing  the  inner  end  of  Poupart's  ligament  and  the 
falciform  edge  of  the  fascia  lata  to  the  pectineal  fascia  (i.  e.,  the  pubic 
portion  of  the  fascia  lata). 

In  the  diagnosis  between  femoral  and  inguinal  hernia,  Poupart's 
ligament  and  the  pubic  spine  are  the  two  important  landmarks.  The  neck 
of  a  femoral  hernia  is  below  the  former  and  external  to  the  latter;  that  of 
an  inguinal  hernia  has  the  opposite  relations,  though  it  often  crosses 
the  spine,  lying  in  front  of  it. 

The  diagnosis  is  easy  in  scrotal  hernia?,  in  thin  subjects,  and  when 
the  hernise  are  reducible  so  that  the  relations  of  the  neck  of  the  sac  to 
the  landmarks  can  be  examined.  It  is  easier  in  men  than  in  women 
because  of  the  greater  ease  of  examining  the  inguinal  canal  in  the  former. 
In  women,  owing  to  its  small  size,  the  inguinal  canal  can  only  be  satis- 
factorily examined  when  there  is  an  inguinal  hernia.  In  irreducible 
hernise  we  must  depend  upon  the  position  of  the  hernia  relative  to 
Poupart's  ligament  and  the  pubic  spine,  a  femoral  hernia  being  altogether 
below  the  former  and  external  to  the  latter.  In  fat  subjects  we  may  not 
be  able  to  feel  Poupart's  ligament  even  in  its  inner  half,  but  the  furrow 
of  the  groin  nearly  corresponds  to  it,  or  we  may  draw  a  line  between  its 
bony  attachments,  finding  the  pubic  spine  in  males  by  invaginating 
the  scrotum. 
So-called  hernia  adiposa  is  not  a  real  hernia  but,  from  its  position  and 


THE  POSTERIOR  ABDOMINAL  WALL  307 

form,  it  may  give  difficulty  in  diagnosis  here  as  with  other  forms  of  hernia. 
It  is  a  lipoma  of  the  subperitoneal  tissue,  which  in  its  growth  takes  the  same 
course  as  a  hernia.  It  is  irreducible  and  tends  to  draw  the  peritoneum 
after  it,  thus  forming  a  pouch  which  may  be  the  starting  point  of  a  true 
hernia. 

Irregular  and  rare  forms  of  femoral  hernia  may  occur:  (1)  To  the  outer 
side  of  the  artery;  (2)  hourglass-shaped  hernia  due  to  the  escape  of  a 
part  of  the  hernia  through  a  rent  in  one  of  the  covering  layers,  generally 
the  cribriform  fascia;  (3)  within  the  proper  sheath  of  the  vessels,  etc. 


THE   POSTERIOR  ABDOMINAL   WALL. 

Hiac  Region. — This  region,  the  lowest  part  of  the  posterior  abdominal 
wall,  corresponds  to  the  iliac  fossa  and  is  bounded  below  by  Poupart's 
ligament,  internally  by  the  pelvic  brim  (iliopectineal  line),  above  and 
externally  by  the  iliac  crest.  The  right  and  left  iliac  fossse  are  separated 
from  each  other  by  the  pelvic  cavity.  It  is  comparatively  small  in  chil- 
dren and  attains  its  size  about  the  time  of  puberty.  It  can  be  examined 
only  through  the  abdominal  wall,  which  should  be  relaxed  by  flexion 
of  the  thigh. 

In  studying  this  region  layer  by  layer  from  before  backward,  we 
notice  : 

1.  Parietal  Peritoneum. — This  becomes  continuous  with  that  lining 
the  anterolateral  abdominal  wall  along  the  iliac  crest  and  Poupart's 
ligament,  where  it  is  loosely  attached  by  means  of  the  next  layer  so  as  to 
be  easily  raised  up. 

2.  1  he  subperitoneal  tissue  is  here  very  abundant  and  loose,  and 
contains  more  or  less  fat.  It  is  continuous  with  the  like  layer  in  the 
neighboring  regions  of  the  abdominal  parietes,  the  anterolateral  region 
below  and  externally,  the  lumbar  above  and  the  pelvis  internally  (the 
latter  including  the  tissue  between  the  folds  of  the  broad  ligaments  in 
the  female). 

Its  looseness  furors  the  spread  of  abscess.  Such  an  abscess  may  originate 
in  a  viscus  which  occupies  this  region,  the  cecum  or  appendix  on  the 
right,  the  sigmoid  flexure  on  the  left.  The  infection  may  reach  this 
Layer  by  passing  along  the  lymphatics  ot  the  tissue  lying  between  the 
layers  of  peritoneum  which  attach  the  viscus.  On  the  other  hand,  an 
abscess  in  this  ti  sue  may  perforate  and  discharge  into  one  of  these  viscera. 
tin,  such  an  abscess  may  sink  down  from  the  lumbar  region  or  rise 
up  from  the  pelvis,  as  iii  cases  of  retroperitoneal  pelvic  abscess  or  pelvic 
cellulitis  in  the  female. 

Absces  in  this  tia  ue  i  more  common  on  the  right  side  owing  to  the 
presence  of  the  appendix.  As  a  rule,  it  sinks  to  the  level  of  Poupart's 
ligament,  and  here  it  collect,  and  displaces  upward  the  peritoneum  from 
the  iliac  fascia  behind  and  the  transversalis  fascia  in  front  and  "points" 
above  Poupart's  ligament  (Fig.  I07j.  Just  above  this  ligament  it 
may  \><-  opened  by  incising  the  transver  ali    fa  icia  and  the  overlying 


308 


THE  ABDOMEN 


layers  without  opening  the  peritoneum,  as  it  is  displaced  upward. 
This  was  the  course  of  many  abscesses  originating  in  the  appendix,  the 
so-called  perityphlitic  abscesses,  before  the  adoption  of  the  modern  opera- 
tion for  appendicitis. 

Many  cases  of  abscess  resulting  from  pelvic  cellulitis  open  or  are  opened 
here.  Occasionally  pus  collecting  here  escapes  into  the  upper  and  inner 
aspect  of  the  thigh  through  the  femoral  ring  or  along  the  iliac  vessels, 
which  lie  in  this  layer,  or  it  may  sink  into  the  pelvis. 

Structures  in  the  Subperitoneal  Layer. — The  external  iliac  artery  and 
vein,  spermatic  or  ovarian  vessels,  genitocrural  nerve,  ureter,  and  vas 
deferens,  or  round  ligament. 


Fig.  107 


EXTERNAL 

OBLIQUE 

APONEUROSIS 

TRANSVERS 
LIS   FASCIA 


CESS 
VING 
ISED  UP 
E    PERI- 
NEUM 


FASCIA   LATA 


Diagram  representing  the  displacement  of  the  peritoneum  by  an  abscess  in  the  subperitoneal 
tissue  of  the  iliac  fossa.      The  white  dotted  line  indicates  peritoneum.      (Tillaux.) 


External  Iliac  Vessels. — The  course  of  the  artery  is  represented  by  a 
line,  slightly  convex  laterally,  from  a  point  12  mm.  (^  in.)  to  the  left  of  and 
below  the  umbilicus  and  directed  downward  and  outward  to  Poupart's 
ligament,  a  little  internal  to  its  centre,  or  half-way  between  the  anterior 
superior  iliac  spine  and  the  symphysis  pubis.  The  upper  5  cm.  (2  in.)  of 
this  line  would  represent  the  common  iliac  artery,  the  lower  two-thirds, 
or  the  part  below  the  level  of  the  lumbosacral  articulation,  the  external 
iliac. 

The  vein  lies  to  its  inner  side,  passing  behind  it  above  on  the  right 
side  so  as  to  reach  the  outside  of  the  right  common  iliac  artery. 


THE  POSTERIOR  ABDOMINAL  WALL  309 

Position. — These  vessels  lie  upon  the  inner  border  of  the  psoas  muscle 
along  the  brim  of  the  pelvis  in  a  fibrocellular  sheath,  connected  with  the 
iliac  fascia,  which  separates  it  from  the  muscle. 

Relations. — The  external  iliac  vessels  are  crossed  in  front  by  the 
sigmoid  flexure  on  the  left  and  the  end  of  the  ileum  on  the  right  side. 
The  ureter  sometimes  crosses  over  their  upper  end  instead  of  over  the 
bifurcation  of  the  common  iliac  vessels.  The  spermatic  vessels  and  the 
genital  branch  of  the  genitocrural  nerve  lie  upon  the  lower  part  of  the 
artery  for  a  short  distance,  and  the  deep  circumflex  iliac  vein  crosses  it 
just  above  its  lower  limit.  The  vas  deferens  in  the  male,  and  the  round 
ligament  and  ovarian  vessels  in  the  female,  cross  it  to  reach  the  pelvis. 
The  crural  branch  of  the  genitocrural  nerve  descends  on  the  antero- 
lateral aspect  of  the  artery. 

These  relations  should  be  borne  in  mind  in  ligature  of  the  external 
iliac  artery.  In  this  operation,  whose  principal  indication  is  femoral 
aneurysm,  the  most  important  relations  are  those  of  the  vein,  for  the 
ligature  is  passed  from  the  venous  side,  and  the  relations  to  the  loose 
subperitoneal  tissue,  for  the  latter  allows  the  exposure  of  the  vessel  by 
permitting  the  raising  up  of  the  peritoneum  from  the  iliac  fossa  through 
an  incision  along  the  lower  or  outer  border  of  the  region. 

The  incision  may  be  made:  (1)  slightly  above  and  parallel  with  the 
outer  half  of  Poupart's  ligament;  or  (2)  parallel  with  and  over  the  course 
of  the  artery,  a  little  external  to  the  course  of  the  deep  epigastric,  so  as 
to  avoid  the  latter,  and  commencing  a  little  above  Poupart's  ligament. 

In  (1)  we  incise  the  external  oblique  aponeurosis,  the  conjoined  tendon 
along  its  attachment  to  Poupart's  ligament,  and  the  transversalis  fascia, 
to  expose  the  loose  subperitoneal  tissue,  in  which  the  artery  lies  in  front 
of  the  iliac  fascia.  In  this  tissue  at  the  inner  angle  of  the  incision  the  deep 
epigastric  artery,  if  exposed,  should  be  retracted  inward  and  upward. 
The  peritoneum  is  then  bluntly  detached  from  the  iliac  fossa,  from 
behind  Poupart's  ligament  upward  and  inward  to  the  inner  border  of 
the  psoas,  which  forms  a  convenient  landmark  for  the  artery. 

There  is  danger  of  wounding  the  deep  circumflex  iliac  vessels  by 
incising  too  close  to  Poupart's  ligament  and  of  wounding  the  deep 
epigastric  vessels  by  incising  too  far  internally.  Mesially  the  incision 
is  not  commonly  carried  beyond  the  level  of  the  internal  abdominal  ring, 
as  that  is  slightly  internal  to  the  middle  of  Poupart's  ligament,  but  even 
if  it  should  be,  there  is  a  full  12  nun.  ( ',  in.)  between  the  ligament  and  the 
ring,  so  that  the  latter  need  not  be  injured  unless  the  incision  is  too  high. 

After  separating  the  artery  from  the  vein,  through  the  loose  tissue 
which  forms  a  kind  of  sheath  for  it,  the  artery  is  tied  by  a  ligature  passed 

from  within  outward  about  3  em.  (I1,  in.)  above  Poupart's  ligament,  to 
avoid  the  proximit  \  of  collateral  branches  and  important  relations.  The 
crural  branch  of  the  genilocrural  nerve  should  not  be  included  in  the 
ligature. 

In  (2  the  principle  is  (he  same,  but  the  artery  is  exposed  at  greater 
depth,  and  there  i-  more  danger  of  hernia,  while  the  deep  epigastric  and 
circumflex    iliac   vessels   ami    the    internal    ring  are    in    no  danger.      The 


310  THE  ABDOMEN 

artery  may  also  be  tied  higher  up  and  the  skin  incision  is  farther  from  the 
groin  in  case  an  aneurysm  bulges  there. 

At  the  present  time  the  transperitoneal  method  is  preferred  by  many. 
It  also  allows  the  ligature  of  the  common  iliac.  The  chief  objections  are 
those  common  to  abdominal  incisions  and  intraperitoneal  operations. 
I  have  found  McBurney's  suggestion,  the  compression  of  the  common 
iliac  by  an  assistant's  finger,  introduced  through  an  oblique  intermuscular 
abdominal  incision,  most  efficient  and  useful  in  amputation  at  the  hip 
joint. 

The  common  iliac  artery  may  be  reached  and  tied,  extraperitoneally, 
by  an  extension  of  the  incision  (1)  for  the  external  iliac  upward  toward 
the  lower  ribs,  or  upward  and  inward  toward  the  umbilicus.  This  opera- 
tion is  very  rarely  called  for,  but  through  such  an  incision  the  lower 
ureter  may  be  exposed. 

The  collateral  circulation  after  ligation  of  the  external  iliac  artery  is 
derived  from  the  anastomosis  of  the  deep  epigastric  with  the  internal 
mammary,  obturator,  lumbar,  and  lower  intercostals ;  of  the  deep  cir- 
cumflex iliac  with  the  iliolumbar;  of  the  internal  circumflex  with  the 
obturator;  of  the  external  circumflex  with  the  gluteal;  of  the  external 
pudic  with  the  internal  pudic,  and  other  minor  anastomoses. 

The  external  iliac  lymph  nodes,  eight  to  ten  in  number,  extend  in  three 
linear  chains  along  the  anterior  and  inner  aspect  of  the  external  iliac 
vessels.  The  internal  chain,  placed  below  and  internal  to  the  vein,  is  on 
the  lateral  pelvic  wall.  As  the  external  iliac  nodes  receive  the  lymphatics 
from  the  inguinal  nodes  and  those  accompanying  the  deep  epigastric 
and  deep  circumflex  iliac  arteries  as  well  as  lymphatics  from  the  bladder, 
prostate,  glans  penis,  clitoris,  cervix,  upper  vagina,  etc.,  they  may  be 
enlarged  from  infection  from  these  sources.  We  may  palpate  them,  when 
enlarged,  through  the  abdomen,  except  in  very  fat  subjects,  and  so  deter- 
mine the  extent  of  the  lymphatic  infection  in  septic  or  cancerous  cases. 
These  nodes  when  enlarged  may  cause  persistent  edema  of  the  lower 
extremity  by  pressure  on  the  external  iliac  vein.  They  may  be  reached 
in  the  same  way  as  the  artery. 

The  Iliac  Fascia. — The  iliac  fascia  covers  the  iliopsoas  muscle.  It  is 
attached  to  bone  and  fascia  around  the  limits  of  this  muscle,  thus  forming 
for  it  a  single  osseofibrous  compartment.  At  the  most  dependent  part 
the  muscle  and  fascia  pass  into  the  thigh.  The  thin  upper  part  sheaths 
the  upper  part  of  the  psoas  and  is  adherent  to  it.  It  ends  above  at  the 
diaphragm  in  a  thickening,  the  ligamentum  arcuatum  internum,  and  is 
attached,  along  the  outer  border  of  the  psoas,  to  the  anterior  layer  of  the 
lumbar  fascia.  The  lower  part,  covering  the  iliacus  and  the  lower  part  of 
the  psoas,  is  thicker  and  separated  from  the  muscle  by  a  thin  layer  of 
fatty  connective  tissue  which  favors  the  formation  or  spread  of  pus.  In 
this  loose  tissue  lie  the  anterior  crural  and  external  cutaneous  nerves,  and 
some  muscular  arterial  branches.  The  large  vessels  are,  therefore, 
separated  by  the  iliac  fascia  from  the  principal  nerves  of  this  region,  save 
the  genitocrural.  The  lower  part  of  the  fascia  is  attached  to  the  iliac  crest 
externally  and  above,  to  the  iliopectineal  line  internally,  while  inferiorly 


THE  POSTERIOR  ABDOMINAL  WALL  311 

it  is  adherent  to  the  outer  4  cm.  (U  in.)  of  Poupart's  ligament,  and  con- 
tinues under  the  latter  into  the  thigh  as  the  sheath  of  the  muscle  as  far  as 
its  insertion.  Internal  to  the  muscle  it  passes  into  the  thigh  behind  the 
vessels,  whose  sheath  it  helps  to  form,  and  is  continuous  with  the  fascia 
covering  the  pectineus,  i.  e.,  the  pectineal  fascia  or  the  pubic  portion  of 
the  fascia  lata.  Between  the  iliopsoas  and  the  pectineus  it  sends  back  a 
fibrous  partition  to  the  pectineal  eminence  and  the  capsule  of  the  hip 
(iliopectineal  septum). 

Although  in  surgery  we  find  that  abscesses  do  not  always  respect 
fibrous  fascial  planes,  but  sometimes  break  through  them,  this  is  less 
true  of  those  beneath  the  iliac  fascia,  especially  as  they  are  mostly  "cold" 
or  tuberculous  abscesses. 

Abscesses  beneath  the  iliac  fascia  are  often  known  as  "psoas  abscesses" 
and  have  a  quite  definite  course.  They  sink  by  gravity  along  the  course 
of  the  muscle,  pass  under  the  outer  half  of  Poupart's  ligament,  and  point 
at  the  upper  and  anterior  part  of  the  thigh,  external  to  the  large  vessels, 
where  they  may  be  safely  opened.  Occasionally  they  do  not  take  this 
course,  but  may  point  elsewhere  after  penetrating  the  fascia.  They  may 
extend  into  the  lumbar  region,  over  the  iliac  crest  into  the  gluteal  region, 
over  the  pelvic  brim  into  the  pelvis,  or  along  the  inguinal  canal  into  the 
scrotum,  and  find  an  exit  in  the  parts  named.  They  may  also  open  above 
instead  of  below  the  fold  of  the  groin.  In  other  cases  a  psoas  abscess 
passes  lower  into  the  thigh,  probably  following  branches  of  the  anterior 
crural  nerve,  where  they  pierce  the  sheath  of  the  iliopsoas. 

We  call  these  abscesses  "psoas  abscesses"  because  most  of  them  are 
due  to  spinal  caries  and  make  their  way  first  into  the  sheath  of  the  psoas. 
If  the  caries  is  in  the  lumbar  spine  direct  extension  into  the  psoas  muscle 
readily  occurs.  The  lumbar  curve  is  likely  to  be  flattened  out  in  such 
cases.  Instead  of  entering  the  psoas  sheath  such  abscesses  may  pass 
behind  it  and  enter  and  point  in  the  lumbar  region,  or  they  may  extend 
between  the  muscular  and  fascial  planes  of  the  anterior  belly  wall.  If 
the  caries  is  in  the  thoracic  vertebra1,  the  pus  descends  by  gravity  in  the 
posterior  mediastinum  along  the  front  of  the  spinal  column  to  the  upper 
end  of  the  psoas.  This  it  penetrates,  like  a  wedge,  between  its  upper 
origins,  i.  e.,  from  the  body  and  the  transverse  process  of  the  first  lumbar 
vertebra,  at  the  same  time  passing  under  the  ligamentum  arcuatum 
internum.  In  time  the  pus  may  more  or  less  entirely  destroy  the  muscle, 
leaving  the  lumbar  nerves  free  id  b  pus  sac 

In  inflammation  of  the  iliopsoas,  or  in  psoas  abscess  before  the  pus 
is  evacuated,  the  thigh  is  kept  flexed,  for  in  this  position  the  muscle  is 
relaxed,  the  abscess  is  Less  tense,  and  the  lumbar  nerves  less  compressed 
and  irritated.  This  relaxation  is  due  to  the  fad  thai  flexion  of  die  (high 
is  the  principal  action  of  the  iliopsoas;  the  outward  rotation,  sometimes 
tciated  with  it,  is  due  to  other  causes,  for  the  iliopsoas  is  not  an  out- 
ward rotator.  According  to  I  [yrtl  the  iliopsoas  cannoi  alone,  <u-  even  with 
the  pectineus,  flex  the  thigh,  so  thai  in  high  amputation  of  the  thigh  the 
patient  cannoi  flea  the  stump  until  the  other  flexors  have  become  adherent 

to  the  JCar  Or  tO  the  bone. 


312  THE  ABDOMEN     - 

Abscess  similar  in  course  to  the  foregoing  may  arise  in  the  iliac  fossa 
which  might  properly  be  called  "iliac  abscess,"  but  this  term  is  more 
often  applied  to  those  in  the  iliac  subperitoneal  tissue. 

In  psoas  abscesses  the  fold  of  the  groin  is  partly  effaced  in  its  outer 
part,  fluctuation  may  be  obtained  below  Poupart's  ligament,  and  a  ful- 
ness is  felt  in  the  iliac  fossa  and,  in  thin  patients,  along  the  course  of  the 
psoas. 

From  the  above  we  see  that  two  well-marked  forms  of  abscess  occur 
in  the  iliac  region,  (1)  in  the  subperitoneal  tissue,  and  (2)  beneath  the 
iliac  fascia,  separated  as  to  their  position  by  the  iliac  fascia. 

The  ilium,  forming  the  iliac  fossa,  separates  this  region  from  the 
gluteal  region  behind,  hence  pus  in  this  region  may  sometimes  gain  access 
to  the  gluteal  region  by  a  perforation  of  the  thin  translucent  bone.  The 
posterior  drainage  of  some  cases  of  abscess  in  the  iliac  fossa,  through  a 
trephine  opening  in  the  bone,  has  in  rare  instances  been  practised,  accord- 
ing to  the  principle  of  draining  at  the  most  dependent  point,  i.  e.,  in  the 
supine  position. 

Tumors,  especially  enchondroma,  osteo-enchondroma,  and  sarcoma, 
occasionally  take  origin  from  the  iliac  bone  or  its  periosteum.  Fracture 
from  direct  violence  may  involve  almost  any  part  of  the  ilium,  the  fossa, 
the  superior  spine  or  the  crest.  The  latter  may  be  separated  entire  as 
an  epiphysis  previous  to  about  the  twenty-fourth  year,  when  it  joins  the 
bone.  In  fractures  through  the  fossa  the  fragments  are  usually  held  in 
position  by  the  muscles  attached  on  either  side,  which  act  as  splints. 
Owing  to  the  many  muscular  attachments,  absolute  rest  is  required  in 
the  treatment  of  fractures  of  the  ilium. 

Lumbar  Region. — The  two  lumbar  regions,  right  and  left,  adjoin  one 
another  in  the  median  line.  They  are  bounded  laterally  by  the  external 
border  of  the  external  abdominal  oblique  muscles;  above  by  the  twelfth 
ribs;  and  below  by  the  posterior  half  of  the  iliac  crests.  On  account 
of  its  boundaries  this  area  is  known  as  the  iliocostal  space.  The  tip  of 
the  twelfth  rib  is,  on  the  average,  5  cm.  (2  in.)  above  the  middle  of  the 
iliac  crest,  but  this  space  may  be  widened  by  lateral  flexion  of  the  body, 
as  it  is  in  operations  in  this  region. 

Superficial  View  from  Behind. — In  the  median  line  we  see  a  vertical 
groove,  the  spinal  furrow,  which  is  due  to  the  prominence  of  the  erector 
spinas  mass  on  either  side  and  to  the  attachment  of  the  skin,  by  means  of 
the  subcutaneous  tissue,  to  the  tips  of  the  lumbar  spinous  processes, 
which  we  feel  in  the  bottom  of  the  groove.  The  spinal  furrow  spreads  out 
below  into  the  angular  interval  between  the  gluteal  muscles.  The  lateral 
margins  of  the  erector  spinse  muscle  can  be  felt  and  usually  seen,  except 
in  fat  subjects.  Lateral  to  the  erector  spina?  mass  the  surface  is  flattened. 
The  anteroposterior  displacement  of  one  or  more  of  the  spines  indi- 
cates an  injury  or  a  disease,  probably  caries  of  the  bodies  of  the  cor- 
responding vertebrae. 

Normally  the  line  of  the  lumbar  spines  and  the  contour  of  the  lumbar 
region  vertically  is  concave  posteriorly  and  slightly  more  so  in  women 
than  in  men.    In  hip  joint  disease,  when  the  joint  is  ankylosed  in  the 


THE  POSTERIOR  ABDOMINAL  WALL 


313 


flexed  position,  this  concavity  is  much  increased  on  extending  the  thigh, 
giving  rise  to  the  deformity  known  as  lordosis,  and  it  is  flattened  out 
on  flexing  the  thigh  beyond  the  angle  at  which  it  is  ankylosed.  These 
are  important  diagnostic  points,  and  are  due  to  the  very  free  flexion 
and  extension  in  the  lumbar  vertebrae  which  occur  when  the  pelvis  is 
tilted  and  take  the  place  of  the  similar  movements  in  the  hip. 

A  horizontal  line  connecting  the  highest  points  of  the  iliac  crests  cor- 
responds to  the  spine  of  the  fourth  lumbar  vertebra.  In  the  interspace 
above  (or  below)  this  spine  lumbar  puncture  is  practised.  This  is  below 
the  spinal  cord,  which  reaches  to  the  top  of  the  second  lumbar  vertebra. 

The  Subcutaneous  Tissue. — The  subcutaneous  tissue  is  a  thick  dense 
laver  containing  comparatively  little  fat  and  connected  closely  with  the 
skin,  but  only  loosely  with  the  fascia  beneath,  thus  allowing  large  extra- 
vasations of  blood  or  of  a  serosanguineous  fluid  from  glancing  blows. 


Fig.  108 


COMPARTMENT    OF 


TRANSVERSA- 
LIS    MUSCLE 

INT.   OBLIQUE    MUSC. 
EXT.  OBLIQUE  MUSC. 


UPERFICIAL 
FASCIA 


ISSIMUS 
MUSCLE 


Transverse  section  at  level  of  the  second  lumbar  vertebra,  to  show  the  position  of  the  kidney, 
the  lumbar  fasr-iu,  and  tin-  posterior  attachment  of  the  uhdominal  muscle  (the  external  oblicjue 
is  drawn  too  mar  the  median  line;. 

Superficial  Muscles.  The  latissimus  dorsi,  like  the  external  abdominal 
oblique,  i>  attached  to  the  outer  li|>  of  the  iliac  crest.  At  the  midpoint 
of  the  crest  an  interval  usually  exists  between  these  two  muscles,  which 
is  triangular  in  shape  owing  to  their  converging  above.  This  triangle, 
with  its  base  below  at  the  crest,  is  known  as  the  triangle  of  Petit,  and  is  a 
weak  spot  representing  a  lack  of  one  of  the  muscular  layers.  Hence  it 
IS  thai  a  nire  form  of  hernia,  lumbar  hernia,  occurs  here,  and  it  is  a  favorite 
pot  for  the  pointing  of  lumbar  abscesses.  Its  floor  is  formed  by  the 
internal  oblique  muscle,  which  overlaps  the  external  oblique  posteriorly, 
and   thua   comes   in   contact    with   the  subcutaneous  tissue   ill   this  small 

triangular  area.  Above,  in  another  triangular  area  bounded  by  the 
twelfth  rib  above,  the  internal  oblique  externally,  and  the  quadratus 
lumborum  internally,  the  posterior  aponeurosis  of  the  transversalis  is 
only  covered  by  the  lati  limu   dor  i  muscle. 

Both   the  internal  oblique  and   the  latissimus  dorsi  are  attached  to  the 

dense  posterior  layer  of  the  lumbar  fascia  (Fig.  108). 


314  THE  ABDOMEN 

The  lumbar  fascia,  the  posterior,  middle,  and  anterior  layers  of  this 
fascia  are  attached  mesially  to  the  tips  of  the  lumbar  spines,  the  tips  of 
the  lumbar  transverse  processes,  and  the  front  of  the  bases  of  the  latter 
respectively.  Laterally  they  join  together  and  thus  form  two  osseofibrous 
compartments  for  the  two  vertical  muscles  of  this  region,  the  erector  spinse 
and  the  quadratus  lumborum. 

The  posterior  joins  the  middle  layer  of  the  fascia  at  the  outer  border 
of  the  erector  spinse.  The  middle  layer,  thus  reinforced,  joins  the  anterior 
layer  of  the  fascia  at  the  outer  border  of  the  quadratus  lumborum.  The 
combination  of  these  three  layers,  about  7.5  cm.  (3  in.)  from  the  tips  of 
the  lumbar  transverse  processes,  forms  a  fascia  which  gives  origin  to  the 
transversalis  muscle,  and  hence  is  called  the  posterior  aponeurosis  of  the 
trans versalis  muscle,  a  name  sometimes  applied  to  the  entire  fascia.  The 
posterior  layer  forms  a  part  of  or  blends  with  the  thick  vertebral  aponeu- 
rosis covering  the  muscles  of  the  back. 

The  posterior  and  middle  layers,  where  they  form  the  sheath  of  the 
erector  spinse,  are  very  thick  and  strong,  hence  abscesses  seldom  if  ever 
penetrate  the  erector  spinse  muscle  unless  they  originate  in  the  bones  of 
the  neural  arch,  with  which  the  muscle  is  in  contact.  On  the  other  hand, 
the  anterior  layer,  covering  the  front  of  the  quadratus  lumborum,  is 
very  thin,  and  is  in  contact  with  the  subperitoneal  tissue  in  relation 
with  the  kidney  and  colon. 

The  lumbar  fascia  is  very  variously  described,  but  the  weight  of  author- 
ity makes  the  transversalis  fascia  continuous  with  the  anterior  layer  of 
the  lumbar  fascia;  the  other  differences  of  description  are  of  no  practical 
importance.  The  important  point  is  that  we  have  three  fascial  layers, 
forming  two  muscular  sheaths,  continuous  with  the  posterior  aponeurotic 
attachment  of  the  transversalis  muscle,  giving  attachment  to  other  muscles 
and  directing  the  course  of  abscesses,  etc. 

Abscess  starting  in  the  lumbar  subperitoneal  tissue  may  readily  per- 
forate the  anterior  fascial  layer,  enter  and  pass  through  the  thin  quad- 
ratus muscle,  and  perforate  its  posterior  sheath  external  to  the  outer 
border  of  the  erector  spinse.  Or  it  may  perforate  the  posterior  apon- 
eurosis of  the  transversalis  external  to  the  quadratus  muscle.  In  certain 
cases  this  may  be  facilitated  by  the  abscess  following  the  last  thoracic  or 
the  iliohypogastric  nerves,  where  they  pierce  this  aponeurosis,  below  the 
last  rib  and  above  the  iliac  crest  respectively.  In  either  case  the  abscess 
comes  to  lie  under  the  internal  oblique  and  its  posterior  aponeurotic 
attachment.  The  common  course  is  then  to  perforate  the  latter  and  sink 
to  the  triangle  of  Petit  or  to  the  outer  border  of  the  erector  spinse,  where 
it  appears  as  a  lumbar  abscess. 

Muscles. — The  thick  erector  spinas  has  a  dense  fascial  sheath  which 
we  avoid  opening  in  lumbar  incisions,  for  little  or  no  room  is  thereby 
gained  and  we  thus  avoid  the  danger  of  suppuration  within  the  sheath. 
The  erector  spinse  mass  occupies  the  entire  vertebral  groove  on  each  side 
and  projects  beyond  it  laterally.  Its  outer  border,  limited  by  the  union  of 
the  posterior  and  middle  layers  of  the  lumbar  fascia,  is  readily  felt  about 
8.5  cm.  (3J  in.)  from  the  middle  line  and  forms  an  excellent  landmark  in 
making  transverse  or  oblique  lumbar  incisions. 


THE  POSTERIOR  ABDOMINAL  WALL  315 

The  thin  flat  quadratus  lumborum  is  considerably  broader  than  the 
erector  spina-  below,  and  thus  extends  beyond  it  laterally,  where  it  is  itself 
overlapped  by  the  internal  oblique.  At  its  upper  narrower  end  it  no  longer 
overlaps  the  erector  spina-,  which  is  here  broader  than  below.  The  outer 
third  or  so  of  the  thin  quadratus  muscle,  unsupported  by  the  erector 
spinas,  offers  less  resistance  to  protrusions  from  within  than  the  inner  two- 
thirds.  The  outer  border  of  the  quadratus  lumborum  forms  the  most 
valuable  landmark  in  lumbar  operations.  This  border  is  not  vertical,  but 
inclines  inward  as  it  passes  upward.  Just  above  the  iliac  crest  it  corre- 
sponds to  a  line  drawn  vertically  from  the  middle  of  the  crest,  hence  it 
corresponds  to  the  position  of  Petit's  triangle.  Midway  between  the  crest 
and  the  last  rib  it  may  be  about  2.5  cm.  (1  in.)  internal  to  the  above  line. 

Incisions. — Vertical  lumbar  incisions  are  made  from  a  point  12  to  25 
mm.  (h  to  1  in.)  mesial  to  the  middle  of  the  iliac  crest,  so  as  to  meet  the 
outer  border  of  the  quadratus  about  the  middle  of  the  lumbar  region. 
This  line  of  incision  also  corresponds  to  the  course  of  the  colon.  This 
vertical  incision  is  objectionable  because  it  divides  the  lumbar  and  last 
thoracic  vessels  and  nerves,  which  cross  its  course,  and  it  affords  com- 
paratively little  room.  Hence  an  oblique  incision,  commencing  in  the 
costovertebral  angle  near  the  outer  border  of  the  erector  spina-,  is  prefer- 
able, as  it  parallels  the  vessels,  the  nerves,  and  the  natural  creases  and 
cleavage  lines  of  the  skin  of  this  region.  If,  as  is  often  done,  we  incise 
just  below  the  twelfth  rib,  the  latter  should  be  determined  by  counting 
from  above,  for  I  loll  has  shown  that  this  rib  is  frequently  rudimentary  and 
so  short  as  not  to  reach  beyond  the  erector  spinse  mass,  so  as  to  be  mis- 
taken for  a  lumbar  transverse  process.  If  the  incision  should  then  be 
made  just  below  the  eleventh  rib  the  pleura  would  be  in  danger  of  being 
opened,  an  accident  that  has  been  recorded  by  Professor  Dumreicher,  of 
\  ienna,  and  others.  In  these  cases  the  lower  edge  of  the  pleura  extends 
from  tin-  lower  border  of  the  last  thoracic  vertebra  nearly  horizontally 
to  the  lower  border  of  the  eleventh  rib.  Exceptionally  also  the  pleura 
may  project  considerably  below  a  normal  twelfth  rib,  so  as  to  require 
caution  in  any  case  at  the  inner  and  upper  angle  of  the  incision.  The  fad 
that  we  may  have  a  correspondingly  high  level  of  the  pleura  with  a  rudi- 
mentary twelfth  rib  makes  the  above  caution  no  less  imperative  in  all 

The  oblique  incisions  extend  laterally  a  variable  distance  beyond  the 
Lumbar  region,  ami  divide  in  the  superficial  muscular  layer,  the  latis- 

jimu  \  dorsi,  and  the  external  oblique;  in  the  next  deeper  layer  the  internal 

oblique  and  its  posterior  aponeurosis;  and  beneath  this  the  transversalis 
and  it-  posterior  aponeurosis,  including  that  part  of  it  forming  the  dorsal 
layer  of  the  -heath  of  the  quadratus  muscle.    Retracting  the  outer  border 

of  the  latter  muscle  inward,  or  incising  it  if  necessary  to  gain  more  room, 

we  inci  e  it-  anterior  fascial  covering,  and  the  transversalis  fascia  continu- 

oii    with  it,  and  reach  the  subperitoneal  connective  tissue  in  relation  to  the 

kidne.    and   colon.      If  is  in   this   tissue,   which   lure  contains   much  fat, 

that   perinephriiic  and  pericolic  abscisses  develop.     The  hitter  occur 

molly  on  the  right  side,  being  due  to  the  appendix.     We  have  shown 


316  THE    ABDOMEN 

above  their  most  common  course  (lumbar  abscess,  p.  314),  but  they  may 
also  sink  in  the  subperitoneal  tissue  into  the  iliac  fossa  or  pelvis,  and  not 
infrequently  they  burrow  through  the  diaphragm  and  parietal  pleura 
and  so  enter  the  pleural  cavity  (p.  239). 

The  Vessels. — The  vessels  are  the  subcostal  (twelfth  or  last  thoracic), 
and  the  four  lumbar  arteries  and  their  accompanying  veins.  Of  these, 
the  subcostal  and  first  lumbar,  and  sometimes  the  last  lumbar,  pass 
outward  in  front  of  the  quadratus  lumborum,  and  behind  the  anterior 
layer  of  the  fascia;  the  others  lie  behind  the  quadratus.  Beyond  the  lateral 
border  of  this  muscle  they  pass  forward  between  the  muscular  layers 
of  the  anterior  abdominal  wall  and  anastomose  with  the  vessels  found 
there,  as  well  as  with  those  above  and  below.  The  veins  on  either  side 
are  connected  by  a  vertical  trunk,  the  ascending  lumbar  vein,  which, 
continued  into  the  azygos  vein  of  each  side,  furnishes  an  anastomotic 
channel  in  case  of  obstruction  of  the  inferior  cava. 

Lymphatics. — The  superficial  vessels  empty  into  the  inguinal  nodes, 
the  deep  lymphatics  accompany  the  bloodvessels  and  empty  into  the 
lumbar  nodes  along  the  abdominal  aorta. 

Nerves. — The  twelfth  thoracic  and  the  iliohypogastric  and  ilio-inguinal 
branches  of  the  first  lumbar  nerves  lie  in  front  of  the  quadratus  lum- 
borum and  behind  the  anterior  layer  of  its  sheath;  the  first  named  a 
little  below  and  parallel  with  the  twelfth  rib,  the  others  nearly  parallel 
with  it  and  successively  lower.  The  three  nerves  just  named  pass  behind 
the  kidney  obliquely  from  within,  outward  and  downward.  Pressure 
upon  them  by  a  perinephritic  abscess  or  a  large  tumor  of  the  kidney  may 
give  rise  to  pain  in  the  areas  of  their  distribution.  Thus  in  a  case  of 
perinephritic  abscess  I  have  seen  the  principal  pain  in  the  lateral  gluteal 
region  and  over  the  outside  of  the  hip,  which  are  supplied  respectively 
by  the  large  lateral  cutaneous  branches  of  the  last  thoracic  and  the  ilio- 
hypogastric nerves.  The  same  renal  lesions  may  cause  flexion  of  the  thigh 
from  pressure  on  the  branches  of  the  second  and  third  lumbar  nerves 
supplying  the  iliopsoas  and  pectineus  muscles. 

The  obliquely  transverse  direction  of  the  vessels  and  nerves  of  this 
region  renders  them  liable  to  division  by  vertical  lumbar  incisions,  but 
not  by  obliquely  transverse  ones,  a  point  of  superiority  of  the  latter 
incisions.  The  small  size  of  the  vessels  renders  their  division  compara- 
tively unimportant. 

Wounds. — Wounds  of  the  region  are  rare,  and  are  likely  to  be  serious 
only  when  lateral  to  the  erector  spinse  mass,  where  the  abdominal  wall 
is  thinner.  Contusions  may  cause  an  injury  to  the  viscera  (kidney  most 
often,  possibly  also  the  colon)  without  any  appreciable  sign  of  injury 
superficially. 

In  the  reclining  position  the  peritoneal  aspect  of  the  lumbar  region 
is  on  a  lower  level  than  that  of  the  iliac  fossa,  hence  pus  or  other  fluid, 
if  free  in  the  latter  region,  tends  to  gravitate  to  the  former.  This  is 
to  be  carefully  borne  in  mind  in  operating  for  appendicitis,  where  pus 
external  to  the  cecum  and  colon  should  be  prevented  from .  gravitating 
into  this  region  by  gauze  packing. 


THE  POSTERIOR  ABDOMINAL  WALL  317 

The  Abdominal  Cavity. — The  form  of  the  cavity  is  that  of  an  oval 
with  its  larger  end  above.  Owing  to  the  obliquity  of  the  diaphragm, 
the  main  axis  of  the  cavity  is  oblique  from  above  downward,  forward,  and 
to  the  right,  and  is  directed  to  the  right  pubic  spine.  This  is  given  as  one 
reason  for  the  greater  frequency  of  hernia  on  the  right  side.  The  obliq- 
uity of  the  axis  of  the  pelvis  is  from  above  downward  and  backward,  so 
that  in  parturition  and  forced  defecation  or  urination  the  body  is  flexed 
to  bring  these  two  axes  in  the  same  vertical  plane,  so  that  the  abdominal 
pressure  may  act  to  the  greatest  advantage  in  the  pelvis. 

The  abdominal  cavity  is  not  identical  with  the  'peritoneal  cavity,  for 
several  of  the  abdominal  viscera  are  extraperitoneal,  being  only  partly 
covered  by  peritoneum  (kidney,  duodenum,  etc.).  Such  viscera  may  be 
wounded  or  operated  upon  without  involving  the  peritoneum,  which  is 
necessarily  involved  under  similar  circumstances  in  the  case  of  the  intra- 
peritoneal viscera  (stomach,  small  intestine,  spleen,  etc.).  Similarly  peri- 
tonitis is  very  apt  to  be  caused  by  inflammation  or  perforative  ulceration 
of  the  intraperitoneal  viscera,  but  not  necessarily  by  that  of  the  extra- 
peritoneal viscera.  Thus  a  large  perinephritic  abscess  very  rarely  involves 
the  peritoneum,  while  inflammation  of  the  appendix  or  perforation  of 
the  small  intestine  sets  up  a  local  or  general  peritonitis.  ■ 

The  Peritoneum. — The  Parietal  Peritoneum. — The  parietal  peritoneum 
lines  the  deep  surface  of  the  abdominal  wall  and  the  extraperitoneal 
viscera.  It  is  thin  above,  thicker  below  and  behind,  where  its  more 
abundant  and  fatty  subperitoneal  tissue  connects  it  loosely  with  the 
abdominal  wall,  allowing  it  to  be  stripped  up  in  operations  or  by  inflam- 
mations. At  the  umbilicus  it  is  closely  adherent  to  the  belly  wall  and  less 
adherent  along  the  back  of  the  linea  alba.  The  parietal  peritoneum  is 
much  more  sensitive  to  pain  than  the  visceral  layer.  This  is  seen  in 
intraperitoneal  operations  under  cocaine  anesthesia.  Strong  retraction  of 
the  parietal  peritoneum  may  cause  discomfort,  but  if  it  is  inflamed  the 
same  retraction  and  any  handling  may  be  very  painful.  The  visceral 
peritoneum  is  practically  analgesic  unless  traction  is  made  on  its  parietal 
attachment.  The  peritoneum  is  capable  of  great  stretching  if  it  is  effected 
gradually,  as  seen  in  the  pregnant  uterus,  the  distended  bowel,  a  hernial 
sac,  or  an  abdomen  distended  from  various  causes.  According  to 
Buschke,  it  is  capable  of  bearing  a  weight  of  fifty  pounds,  and  its  elasticity 

is  well  shown  by  returning  to  its  previous  condition  after  removal  of  the 
weight  ;)S  well  as,  during  life,  after  the  removal  of  ascites,  large  abdominal 
tumors,  and  the  fetus  at  term.  It  is  possible  for  the  parietal  peritoneum 
to  be  ruptured  by  an  injury  which  does  no  damage  to  any  of  the  viscera. 

Inflammation  of  the  peritoneum  and  its  results  interfere  with  its  disten- 

sibility  and  elasticity ,  SLB.6  may  thus  disturb  the  functions  of  those  organs 
whieh  are  covered  by  peritoneum  and  vary  in  volume  (uterus,  intestine, 
Madder,  ele.  }, 

Penetrating  Wounds.  A  penetrating  wound  of  the  abdomen  is  one 
whieh  penetrates  the  peritoneum  as  well  as  the  other  layers  of  the  parietes. 

Such   WOUnds  an-   much   marc  SeTlOUS  than  those   which   reach    to  hut   not 

through  this  layer,  for  while  it  is  ea  j  to  sel  up  inflammation  (peritonitis) 


318  THE  ABDOMEN 

from  its  inner  surface,  the  outer  surface  may  be  bathed  with  the  pus  of 
an  abscess  or  extensively  stripped  up  in  operations  without  ill  effects. 
This  difference  is  largely  due  to  the  relative  delicacy  and  vulnerability  of 
the  endothelial  inner  surface,  the  spread  of  the  infection  to  the  opposed 
surfaces,  and  its  diffusion  by  the  movements  of  the  intestines.  The 
fact  of  penetration  in  an  abdominal  wound  is  often  difficult  to  deter- 
mine clinically,  and,  in  the  absence  of  definite  symptoms,  we  are  justi- 
fied in  enlarging  bullet  and  stab  wounds,  rather  than  in  exploring  with 
the  probe. 

The  resistance  of  the  peritoneum  to  infection  is  usually  greater  the 
nearer  normal  its  endothelial  coat.  It  is  lessened  when  the  latter  is 
subjected  to  traumatism,  such  as  handling,  rubbing,  drying,  and  to  chem- 
ical irritants,  such  as  strong  antiseptics.  If  infection  does  not  occur 
under  such  conditions,  the  peritoneum  exhibits  its  important  property 
of  forming  plastic,  adhesive  exudates  which  become  organized  into  firm 
adhesions.  This  also  occurs  in  the  presence  of  infection,  and  is  largely 
a  conservative  process,  for  the  infected  or  injured  area  is  thereby  isolated, 
which  prevents  a  serious  diffusion  of  inflammation.  By  the  stretching  of 
these  adhesions  there  may  be  formed  a  variety  of  bands  beneath  which 
loops  of  intestine  may  be  caught  and  strangulated.  The  tendency  to 
adhesion  is  made  use  of  in  intestinal  suture,  in  which  the  peritoneal 
surfaces  are  turned  in  so  as  to  oppose  one  another.  Firm  adhesion 
occurs  much  sooner  than  when  other  soft  parts  are  united  by  suture. 
Peritoneal  adhesions,  whether  purposely  formed  or  the  result  of  inflam- 
mation, often  show  a  tendency  to  become  smaller,  longer,  and  event- 
ually to  disappear,  when  the  cause  of  irritation  is  removed. 

The  parietal  peritoneum  is  somewhat  less  susceptible  to  infection 
than  the  visceral,  and  certain  regions  present  greater  facilities  for  limiting 
a  peritonitis  by  adhesions  so  as  to  be  less  serious  and  more  amenable  to 
surgical  treatment.  Such  regions  are  the  pelvic,  appendical,  subhepatic, 
lesser  sac,  etc. 

The  Peritoneal  Cavity. — The  peritoneal  cavity  is  merely  a  capillary 
interval  between  the  contiguous  surfaces  of  the  viscera  which  are  covered 
by  peritoneum,  and  between  them  and  the  parietal  peritoneum.  It  is  a 
closed  serous  sac  except  in  the  female,  where  the  openings  of  the  Fal- 
lopian tubes  connect  it  indirectly  with  the  body  surface.  This  sac  con- 
tains just  enough  peritoneal  fluid  to  lubricate  the  surfaces  and  diminish 
friction.  As  a  result  of  various  causes  a  large  amount  of  serous  fluid  may 
be  effused  into  the  peritoneal  cavity.  This  is  known  as  ascites  (from 
rj.ay.oz,  a  skin  bottle),  and  depends  upon  (a)  chronic  inflammation  from 
infection;  (6)  some  abdominal  tumors;  (c)  portal  obstruction;  and 
(d)  general  dropsy  from  cardiac,  renal,  or  pulmonary  disease.  If  the  fluid 
is  small  in  amount  it  collects  in  the  flanks  on  lying  down,  or  the  hypogas- 
tric or  inguinal  regions  on  sitting  up;  if  in  greater  amount  the  flanks  are 
bulged,  the  umbilicus  is  prominent  and  the  intestines  float  on  top  in 
whatever  position  the  body  is  in.  The  fluid  is  dull  or  flat  on  percussion 
and  sharply  marked  off  from  the  tympanitic  resonance  of  the  intestines. 
Breathing  may  be  easier  in  the  sitting  posture,  for  the  compressible 
intestines  then  lie  beneath  the  crowded-up  diaphragm. 


THE  POSTERIOR  ABDOMINAL  WALL  319 

Tapping  of  ascites  may  be  practised  in  the  semilunar  line,  or  preferably 
in  the  linea  alba.  When  the  fluid  is  partly  withdrawn  the  end  of  the  trocar 
is  sometimes  closed  by  the  omentum  or  intestine,  which  can  be  dislodged 
by  introducing  a  probe.  As  the  withdrawal  of  the  fluid,  by  reducing 
the  intra-abdominal  pressure,  causes  a  distention  of  the  deep  abdominal 
veins,  and  thereby  robs  the  heart  of  its  wonted  supply,  syncope  is  liable 
to  occur,  but  may  be  prevented  by  the  pressure  of  an  abdominal  binder. 
A  like  result  may  follow  a  blow  on  the  abdomen,  owing  to  a  paralysis  of 
the  vasoconstrictors. 

The  surface  of  the  peritoneum  is  about  equal  to  that  of  the  skin.  Hence 
we  can  understand  its  enormous  absorbing  function,  taking  up  in  one 
hour  3  to  8  per  cent,  of  the  body  weight.  An  equal  transudation  or  exuda- 
tion may  occur  from  very  toxic  or  irritant  substances.  Fluids  may  pass 
through  the  endothelial  layer  in  many  places;  solids  are  carried  largely 
by  leukocytes  and  are  said  to  pass  only  through  the  intercellular  spaces 
of  the  peritoneum  covering  the  diaphragm  and  thence  into  the  medias- 
tinal lymph  nodes.    The  presence  of  stomata  is  denied  by  Muscatello. 

There  is  normally  a  force  in  the  peritoneal  cavity  which  carries  fluids 
and  foreign  particles  toward  the  diaphragm,  regardless  of  the  position  of 
the  body,  though  either  retarded  or  favored  by  it.  It  has  been  proposed  to 
make  use  of  this  fact  to  carry  off  septic  peritoneal  exudates  by  elevating 
the  pelvis  after  operation.  But,  partly  owing  to  the  greater  danger  of 
toxemia,  the  opposite  position  (Fowler's  position)  is  now  employed,  and 
the  septic  fluid  gravitates  to  the  pelvis,  from  which  it  may  be  drained  off. 
The  peritoneum  in  a  healthy  state  is  capable  of  disposing  of  a  large  num- 
ber of  bacteria,  even  of  pyogenic  varieties,  without  ill  effects;  but  if  there 
is  a  lesion  of  the  membrane,  or  anything  to  arrest  the  normal  absorption, 
so  that  the  bacteria  may  stagnate  and  multiply,  peritonitis  results.  Hence 
the  importance,  as  above  stated,  of  doing  the  least  possible  damage  to  the 
peritoneum. 

If  about  the  focus  of  a  commencing  peritonitis  the  surrounding  parts 
become  glued  together  by  a  plastic  exudate  on  the  peritoneal  surface,  the 
peritonitis  may  be  limited  or  localized,  as  in  most  eases  of  appendicitis. 
If  the  adhesions  are  imperfect,  or  do  not  develop,  or  the  focus  is  more 
diffused,  the  peritonitis  is  spreading  until  if  becomes  general.  In  peri- 
tonitis, especially  in  the  more  acute  mid  general  form,  the  muscular  coal 

<>!'  the  bowel  and  its  nerve  plexuses  may  become  involved,  causing  intes- 
tinal paralysis.  The  result  of  this  is  constipation  Or  complete  obstruction 
of  the  bowels,  and  the  gas,  formed  by  the  decomposition  of  the  intestinal 
contents  produces  distention  of  the  gut,  ineleorism  or  li/iu /xiiiites.      This 

distention,  in  addition  to  the  vasomotor  paralysis,  still  further  increases 
the  paralysis.  Hence  the  danger  of  giving  opium,  which  increases  these 
tendencie  .  Tympanites  also  raises  the  diaphragm  so  that  the  heart  and 
lungs  work  with  difficulty.  The  anatomical  sources  of  infection  which 
give  rise  to  perifoniti  are:  [a)  perforations  or  wounds  of  tin-  viscera  of 
the  alimentary  and  urinary  systems;  d>)  migration  of  bacteria  through 
inflamed  or  itrangulated  gastro-intestinal  walls;  (c)  infection  through 
the  Fallopian  tubes,  (d)  through  wounds  of  the  abdominal  wall,  (e)  or 
through  the  blood  and  lymph  ve   el  .  a    in  tuberculou  i  peritoniti  . 


320  THE  ABDOMEN 

In  peritonitis  the  least  pressure,  even  of  the  bedclothes,  may  be  painful, 
hence  the  patient  lies  with  the  shoulders  raised  and  the  knees  drawn  up, 
to  relax  the  abdomen.  The  abdominal  walls  are  rigid  and  boardlike,  and 
the  diaphragm  is  kept  quiet  to  prevent  movement  of  the  viscera,  respira- 
tion being  thoracic.  In  colic,  on  the  other  hand,  pressure  relieves  the 
pain,  and  the  lax  abdominal  walls  can  be  freely  moved  over  the  bowels. 

The  Visceral  Peritoneum. — The  visceral  peritoneum  besides  covering 
the  intraperitoneal  viscera,  forms  folds  known  as  the  mesenteries  and  false 
ligaments  to  attach  these  viscera  to  the  parietes.  The  visceral  and  parietal 
layers  of  the  peritoneum  are  continuous  by  means  of  these  folds,  some  of 
which  deserve  especial  notice. 

The  Great  Omentum. — The  great  omentum  is  the  elongated  mesentery 
of  the  stomach  which  is  connected  with  its  great  curvature,  or  attached 
margin,  and  descends  as  an  apron  in  front  of  the  bowels,  which  it  sepa- 
rates from  the  abdominal  walls.  In  well-nourished  persons  it  often  con- 
tains considerable  fat,  which  acts  like  a  cholera  band  in  maintaining  an 
even  temperature  of  the  bowels.  In  the  embryo  the  omental  fold  of  the 
mesogastrium  consists  of  four  peritoneal  layers  which  adhere  together  in 
infancy,  and  thereafter  appear  to  consist  of  two  layers  containing  fat  and 
bloodvessels  between  them.  The  lesser  omental  sac  extends  down 
between  the  two  anterior  and  the  two  posterior  omental  layers  before  they 
adhere  together.  The  under  layers,  as  they  pass  up  in  front  of  the  trans- 
colon  and  then  back  to  the  parietes,  become  adherent  to  the  colon  and  to 
the  upper  layer  of  its  mesocolon.  The  portion  of  omentum  extending 
from  the  great  curvature  of  the  stomach  to  the  anterior  surface  of  the 
transverse  colon,  to  which  it  is  attached,  forms  the  gastrocolic  ligament 
or  omentum.  This  and  the  transverse  mesocolon  prevent  our  reaching 
the  posterior  surface  of  the  stomach  without  passing  through  one  or  the 
other  of  them.  When  we  pull  down  the  omentum  the  transverse  colon 
and  stomach  are  pulled  down,  and  the  former  may  be  seen  through  it; 
and  when  we  turn  up  the  omentum  we  see  the  transverse  colon  attached 
to  it.  Hence  the  omentum  may  be  used  to  find  both  the  stomach  and  the 
transverse  colon. 

The  omentum  extends  down  a  variable  distance  into  the  iliac  and  hypo- 
gastric regions,  hence  it  is  very  apt  to  be  found  in  hernia  as  an  epip- 
locele.  This  is  said  to  be  more  common  on  the  left  side  because  the 
omentum  is  more  developed  on  this  side.  It  may  be  the  only  content 
of  a  hernia,  especially  of  a  femoral  hernia,  and  it  is  almost  constant  in 
umbilical  hernise,  except  in  the  congenital  and  infantile  varieties.  (See 
Umbilical  Hernia.) 

The  omentum  generally  contracts  adhesions  to  the  sac  of  a  hernia  in 
which  it  is  present,  provided  the  hernia  is  not  kept  reduced.  Such 
herniee  thus  become  irreducible,  and  the  omentum  may  form  a  kind  of 
second  sac  about  the  gut.  It  often  grows  into  a  large  conglomerate 
fatty  mass,  connected  with  the  rest  of  the  omentum  by  a  narrow  pedicle 
passing  through  the  neck  of  the  sac.  When  the  omentum  in  a  hernia  is 
fit  to  be  returned  to  the  abdomen  the  intestine,  if  present,  should  be 
reduced  first.     In  rare  cases,  especially  in  connection  with  a  hernia  in 


THE  POSTERIOR  ABDOMINAL  WALL  321 

which  the  omentum  has  been  matted  together  and  its  upper  part 
stretched  out  to  a  slender  pedicle,  the  omentum  may  become  twisted 
by  external  influences  until  it  becomes  strangulated.  In  a  recent  case 
of  this  kind  I  found  four  complete  turns  of  the  pedicle. 

As  a  result  of  inflammation  the  omentum  may  contract  adhesions  to 
contiguous  parts  and  so  form  bands,  beneath  which,  as  well  as  beneath 
adhesions  to  a  hernial  sac,  the  bowel  may  be  caught  and  strangulated. 
Strangulation  may  also  occur  through  holes  or  slits  in  the  omentum. 
( Omental  adhesions  may,  under  certain  conditions,  exert  such  a  traction 
upon  the  stomach  and  colon  as  to  produce  functional  disturbance.  A 
benign  effect  of  omental  adhesions  is  seen  where  they  help  to  limit 
inflammatory  or  hemorrhagic  extravasations,  or  to  occlude  a  perforation 
of  the  bowel  due  to  disease. 

The  omentum,  or  sometimes  a  separated  piece  of  it  {omental  graft), 
is  occasionally  similarly  employed  by  the  surgeon  to  fortify  an  intes- 
tinal suture,  by  being  fastened  over  or  around  the  latter.  Ovarian  tumors 
may  be  supplied  with  blood  through  an  adherent  omentum,  in  case  the 
blood  supply  of  the  tumor  is  cut  oft'  by  the  twisting  of  its  pedicle. 

From  its  exposed  position  wounds  of  the  omentum  are  common.  It 
may  plug  a  small  abdominal  wound  and  prevent  the  escape  of  other 
parts.  After  laparotomy  it  is  well  to  replace  the  omentum  over  the 
bowels,  when  there  is  no  contra-indication,  so  as  to  obviate  intestinal 
adhesion  in  the  line  of  the  cicatrix.  As  the  veins  of  the  omentum  empty 
into  the  portal  circulation,  it  is  fastened  to  the  parietal  peritoneum  or 
in  the  subcutaneous  connective  tissue  of  the  abdominal  wall,  in  Talma's 
and  Xa rath's  operations  respectively,  to  establish  a  collateral  circulation 
in  cases  of  portal  obstruction. 

The  Small  Omentum. — The  small  omentum  extending  from  the  trans- 
verse fissure  of  the  liver  to  the  small  curvature  of  the  stomach  helps  to 
hound  i  he  Lesser  peritoneal  sac  in  front.  Its  right  thickened  border  extends 
a  variable  distance  onto  the  first  portion  of  the  duodenum,  where  it  is 
called  the  hepato-duodenal  ligament.  The  latter  bounds  the  foramen  of 
Winslow  in  front  and  contains  between  its  two  thin  layers  the  portal 
vein  the  hepatic  artery,  and  the  common  bile  duct,  the  vein  lying  behind 
the  other  two,  of  which  the  bile  duct  is  to  the  right  of  the  artery.  Its  left. 
extremity  encloses  the  esophagus. 

The  Mesentery.  The  mesentery  is  attached  /<>  the  posterior  abdomi- 
nal wall  lor  about  L5  cm.  (6  in.).  This  attachment  commences  at  a  point 
to  the  lefl  of  the  second  Lumbar  vertebra,  on  a  Level  with  the  attachment 

of  the  lower  fold  of  the  transverse  mesocolon,  the  end  of  the  duodenu  in, 
and  the  lower  border  of  the  pancreas,  and  extends  thence  obliquely 
downward  and  to  the  right,  with  a  slight  convexity  to  (he  left,  l<>  the  right 

iliac  to  ,i,  .  i  to  die  right  sacro-iliac  articulation.  This  attachment  is 
secondary  or  acquired;  it>  real  attachment  is  mesial  and  about  the  origin 
of  the  superior  mesenteric  artery,  as  in  mammals  below  man.  Occa- 
sionally, too,  in  man  we  find  Hie  embryonic  type  of  the  single  median 
me  entery  for  die  entire  bowel. 
At  i» ^  lower  end  the  right  layer  is  continuous  with  the  peritoneum 


322  THE  ABDOMEN 

covering  the  ascending  colon,  and  its  left  layer  with  the  mesentery  of 
the  appendix.  It  forms  a  posterior  longitudinal  'partition  in  the  peri- 
toneal cavity,  and  its  oblique  course  directs  hemorrhagic  or  other  extrav- 
asations on  the  right  side  of  the  abdomen  first  into  the  right  iliac  fossa 
and  on  the  left  side  into  the  pelvis.  Hence  the  greater  frequency  of  col- 
lection of  blood  in  the  right  than  in  the  left  iliac  fossa. 

Between  its  two  layers  are  contained  blood  and  chyle  vessels,  nerves, 
fat  in  varying  quantity,  and  lymphatic  nodes,  the  latter  especially  near 
its  attached  border.  In  addition,  a  band  of  fibrous  tissue  and  plain 
muscular  fibers,  descending  from  the  left  crus  of  the  diaphragm  to  the 
end  of  the  duodenum,  passes  down  between  the  layers  of  the  mesentery, 
and  is  of  sufficient  strength  to  support  the  weight  of  the  intestines  as  well 
as  to  resist  the  pressure  of  the  descent  of  the  diaphragm.  The  -name 
suspensory  muscle  of  the  duodenum  and  mesentery  is  suggested  by  Lock- 
wood  for  this  muscle.  Like  the  omentum  the  mesentery  may  contain 
tumors  or  cysts  of  various  kinds. 

The  length  of  the  mesentery  affords  great  mobility  to  the  small  intestine, 
allowing  it  to  be  displaced  by  tumors,  etc.  The  length  from  its  parietal 
to  its  intestinal  attachment  varies  in  different  parts.  Its  average  length 
is  20  to  22.5  cm.  (8  to  9  in.),  which  it  reaches  not  far  below  its  upper  end. 

That  part  which  is  connected  with  the  intestine  between  points  ISO 
and  330  cm.  (6  and  11  ft.)  below  the  duodenojejunal  junction  attains 
its  greatest  length,  i.  e.,  25  cm.  (10  in.)  (Treves).  This  part  of  the  intestine, 
as  well  as  the  lower  ileum,  is  thus  permitted  to  lie  in  the  pelvis.  Accord- 
ing to  Treves,  when  the  mesentery  is  normal  in  length,  no  part  of  the 
small  intestine  can  be  dragged  onto  the  thigh  through  the  femoral  canal 
(artificially  enlarged)  or  into  the  scrotum  through  the  inguinal  canal, 
and  no  coil  of  intestine  can  be  drawn  out  of  the  abdomen  below  a  hori- 
zontal plane  passing  through  the  pubic  spine.  But  Lockwood  states  that 
it  is  quite  common  in  the  adult  to  find  that  the  small  intestines  will  pass 
3.5  cm.  (1|  in.)  beyond  the  right  crural  arch,  up  to  the  left  crural  arch, 
and  one  inch  below  the  pubic  spine.  Hernise  in  which  the  bowel  occu- 
pies positions  beyond  the  normal  are  common,  and  require,  therefore, 
a  lengthening  or  lowering  of  the  mesentery.  Whether  this  is  always 
acquired,  or  may  sometimes  be  congenital,  has  not  been  definitely 
determined.  According  to  Lockwood,  the  mesentery  is  relatively  longer 
in  infancy,  but  rapidly  decreases  after  the  second  year.  The  same 
author  states  that  prolapse  of  the  root  of  the  mesentery  may  occur  after 
middle  age,  and  such  a  lowering,  rather  than  a  lengthening  of  the 
mesentery,  is  generally  found  in  acquired  hernise.  The  length  of  the 
mesentery  is  an  important  factor  to  be  taken  into  account  in  the  produc- 
tion of  hernia.  The  position  of  the  mesentery  allows  intestinal  hernia 
more  freely  on  the  right  than  on  the  left  side. 

The  mesentery  may  contain  slits,  generally  due  to  injury,  or  round 
holes  of  congenital  origin,  through  which  the  intestine  may  be  strangulated . 
The  round  holes  are  in  an  oval  area  of  the  mesentery  of  the  lower  ileum, 
included  within  an  anastomotic  arch  between  the  ileocolic  and  the  last 
intestinal  branches  of  the  superior  mesenteric  artery,  which  is  often  devoid 


PLATE   XXXII 


FIG.   109 


Outline  of  the  Abdominal  Viscera,  showing  their  Position  with 
Relation  to  One  Another,  the  Ribs  and  Vertebrse.     (Merkel.) 


THE  ABDOMINAL  VISCERA  323 

of  fat,  lymph  nodes  and  visible  bloodvessels,  and  is  so  atrophied  that  a 
knuckle  of  gut  might  easily  be  forced  through  it. 

The  mesentery  is  an  excellent  guide  to  lead  us  to  either  end  of  the  small 
intestine,  as  in  searching  for  intestinal  lesions.  Pulling  forward  a  loop 
of  the  intestine  and  holding  it  vertically  we  trace  its  mesentery  by  sight 
and  touch  back  to  its  parietal  attachment  to  make  sure  that  it  is  not 
twisted,  or  to  untwist  it  if  necessary.  Assured  that  the  mesentery  is  not 
twisted,  by  the  finger  remaining  on  one  side  until  the  posterior  attach- 
ment is  reached  and  followed  into  the  parietal  peritoneum  of  that  side, 
wc  follow  the  intestine  upward  from  the  upper  end  of  the  loop  to  find  the 
duodenojejunal  junction,  and  vice  versa  to  reach  the  lower  end  of  the 
ileum. 

The  Transverse  Mesocolon. — The  transverse  mesocolon  is  7.5  to  10  cm. 
(3  to  4  in.)  deep,  and  with  the  transverse  colon,  reaches  from  the  poste- 
rior to  the  anterior  abdominal  wall  except  at  the  sides  of  the  abdomen, 
where  it  is  shorter.  It  forms  an  imperfect  transverse  septum  between  the 
lower  pari  of  the  peritoneal  cavity,  containing  the  small  intestine,  and  the 
upper  part  containing  the  liver,  stomach,  pancreas,  and  spleen.  To  a 
certain  extent  and  for  a  time  it  may  limit  a  peritonitis  on  one  side  from 
extending  to  the  other.  This  protection  is  also  increased  by  the  omentum 
which  is  attached  to  the  colon  above  and  descends  over  the  front  of  the 
small  intestine.  The  transverse  mesocolon  bounds  the  lesser  peritoneal 
sac  below,  so  that  in  order  to  reach  the  posterior  wall  of  the  stomach, 
to  expose  an  ulcer  on  this  surface  as  well  as  to  do  a  posterior  gastro- 
enterostomy, we  divide  the  mesocolon  vertically  or  parallel  with  its 
bloodvessels. 

The  lesser  peritoneal  sac,  between  the  stomach,  small  omentum  and 
gastrocolic  ligament  in  front  and  the  pancreas,  vtc,  behind,  extends  OB 

the  l.t't  lo  the  >pleen  and  the  left  kidney.  It  opens  into  die  general  peri- 
toneal cavity  by  the  foramen  of  \\'ins/on\  The  latter  normally  admits  two 
(inger>  anil  through  it  an  internal  hernia  may  pass  and  become  strangu- 
lated Efokitansky,  Bkmdin).  This  opening  may  become  narrowed  or 
closed,  especially  in    inlla mutation.      In   case  of  closure  a    kind   of  cys\ 

may  be  formed,  according  to  Malgaigne  and  Begin.    Subdiaphragmatic 

involving   the   lesser  sac    may  be  due  to  gastric,  duodenal,  or 
colic  perforation  or  pancreatic  disease.      The  lesser  sac  may  be  opened 

through  die  small  omentum,  the  gastrocolic  omentum  or  the  transverse 
mesocolon. 

THE  ABDOMINAL  VISCERA. 
The  Stomach  (Figs.   109,  III,  121,   I 

The  Shape.  The  ihape  of  die  stomach  is  like  dial  of  a  somewhat 
flatten-. I   pear,  bent   near  its  smaller  end.     The  esoploo/ns  opens  into  it 

;,i  the  pighi  ide  of  ii  larger  end,  o  thai  die  Litter  projects,  as  the  fundus, 
;,!„■. it  7..".  cm.  3  in  to  the  lefl  of  and  ■".  to  :,  cm.  1 1  \  to  2  in.)  above  the 
esophagi  a)  orifice,  while  the  pylorus,  or  the  opening  into  the  duodenum, 


324  THE  ABDOMEN 

is  at  the  smaller  end.  Therefore  the  length  of  the  lower  or  left  border 
is  the  greater,  hence  the  name  greater  curvature.  The  lesser  curvature 
the  upper  or  right  border,  measures  from  7.5  to  12.5  in.  (3  to  5  in.),  and 
is  only  one-third  or  one-fourth  the  length  of  the  greater  curvature.  The 
latter  is  convex  until  we  approach  the  pyloric  end,  where  there  is  a  slight 
indentation,  between  which  and  the  pylorus  there  is  a  slight  bulging,  the 
antrum  pylori  (or  pyloric  portion),  7.5  to  10  cm.  (3  to  4  in.)  in  length. 
The  lesser  curvature  is  concave  except  over  the  antrum,  where  it  is 
slightly  convex. 

The  pylorus  can  be  seen  as  a  slight  constriction  and  felt  as  a  thickening. 
Its  location  is  best  identified  by  the  position  of  a  thick-walled  vein  which 
extends  across  three-fourths  of  its  breadth  from  below  and  meets,  or 
nearly  meets,  a  similar  vein  from  above  (Mayo).  It  is  the  narrowest 
part  of  the  alimentary  canal,  having  a  diameter  of  12  mm.  (■§■  in.),  hence 
many  objects  may  be  swallowed  which  cannot  pass  the  pylorus  and  must 
be  removed  from  the  stomach  by  gastrotomy.  This  is  especially  common 
among  lunatics,  and  the  number  and  variety  of  articles  swallowed  by  them 
is  remarkable.  It  is  also  remarkable  in  some  instances  how  large  an 
object  can  be  swallowed  and  pass  the  pylorus.  Needles  swallowed  find 
their  way  through  the  stomach  and  bowels  and  appear  at  various  points 
in  the  body.  The  terminal,  18  to  25  mm.  (|  to  1  in.),  the  so-called  pyloric 
canal  of  Jonnesco,  appears  never  to  become  noticeably  dilated,  nor  does 
it  take  part  in  the  grinding  function  of  the  antrum,  and  hence  is  less 
exposed  to  the  effects  of  injury  and  of  the  acid  gastric  contents.  The 
thickening  of  the  circular  fibers,  which  alone  produces  the  valve,  is 
gradual  as  seen  on  the  gastric  side,  but  abrupt  on  the  duodenal.  It  is 
quite  probable  that  the  pylorus  is  normally  closed  and  that  its  opening 
is  an  active  process.  The  pylorus  normally  admits  the  tip  of  the  index 
finger  with  the  invaginated  stomach  wall,  but  it  is  liable  to  obstruction 
or  stenosis  from  several  causes.  The  antrum  pylori  is  elongated  so  that 
when  empty  and  contracted  it  resembles  thick-walled  intestine.  The 
esophageal  is  also  called  the  cardiac  orifice  from  its  close  relation  to 
the  heart.  The  two  surfaces  lying  between  the  two  borders  are  nearly 
symmetrical;  the  ventral  one  looks  also  upward  and  the  dorsal  one 
downward. 

The  shape  changes  with  age;  thus,  some  say  that  it  is  nearly  cylin- 
drical at  birth  and  that  the  fundus,  although  it  grows  rapidly  in  the  first 
year,  does  not  attain  full  development  until  late  in  childhood.  Fetal 
stomachs,  however,  may  possess  a  well-developed  fundus.  In  the  female 
the  stomach  is  relatively  narrower  and  often  more  vertical.  No  definite 
senile  changes  occur.  The  shape  varies  with  the  degree  of  distention. 
In  slight  distention  the  fundus  and  cardiac  portion  are  exclusively 
affected.  As  the  distention  increases  the  antrum  also  becomes  distended, 
but  the  constriction  between  it  and  the  cardiac  portion  persists  until  the 
distention  is  almost  complete.  During  digestion  this  constriction  almost 
completely  separates  the  cardiac  and  pyloric  halves.  In  the  empty  state 
the  cardiac  portion  appears  more  spindle-like,  more  or  less  flattened 
from  before  backward,  and  the  pyloric  half-cylindrical,  from  the  uniformly 


THE  ABDOMINAL  VISCERA  325 

active  contraction  of  the  stomach  wall.  This  is  probably  the  normal 
shape  of  the  empty  stomach  during  life.  We  can  attach  no  clinical  signifi- 
cance to  the  general  shape  of  the  stomach  except  to  abnormalities,  such 
as  those  due  to  diverticula,  bands  and  scars,  and  hourglass  contraction. 
The  latter  may  be  either  pathological,  due  to  contraction  following 
chronic  ulcer,  or,  rarely,  congenital  in  origin.     Diverticula  are  very  rare. 

The  Size. — The  size  of  the  stomach  varies  with  the  age,  sex,  and  degree 
of  distention,  as  well  as  in  certain  pathological  conditions.  The  average 
capacity  at  birth  is  li  ounces  (38  c.c);  at  three  months,  4^  ounces  (150 
c.c);  at  six  months,  6  ounces  (190  c.c);  at  twelve  months,  9  ounces  (280 
c.c);  at  eighteen  months,  12  ounces  (380  c.c).  In  the  adult,  according 
to  Ewald,  its  normal  limit  of  capacity  is  1600  to  1700  c.c,  and  it  cannot 
be  distended  by  more  than  100  c.c.  in  addition  to  this.  In  gastrectasis, 
or  dilatation  of  the  stomach,  the  capacity  may  be  much  increased.  Dila- 
tation of  the  pyloric  portion  is  very  rare,  it  is  the  cardiac  portion  which 
is  principally  involved  in  distention  and  dilatation  of  the  stomach. 

Normally  when  full  its  oblique  or  longest  diameter  measures  25  to  30  cm. 
(10  to  12  in.),  its  greatest  vertical  diameter  (at  the  cardia)  15  cm.  (6  in.), 
it-  anteroposterior  diameter  10  to  12  cm.  (4  to  5  in.)  at  the  fundus  and  3  to 
4  cm.  0i  to  If  in.)  at  the  antrum  pylori.  The  distance  between  its  two 
orifices  varies  from  7.5  to  15  cm.  (3  to  6  in.).  When  empty  and  uniformly 
contracted  it  is  scarcely  larger  in  diameter  than  the  transverse  colon. 
In  the  female  the  stomach  is  smaller  than  in  the  male.  The  weight  of  the 
stomach  is  about  4^  ounces  (140  gm.). 

The  Position. — The  position  of  the  stomach  varies  more  than  that  of 
any  other  viscus,  except  the  small  intestine,  owing  to  its  mobility  and 
varying  size.  It  lies  in  the  left  hypochondrium  and  the  epigastrium,  the 
fundus  being  in  the  former,  the  rest  of  the  stomach  in  the  latter,  region. 
( )nlv  in  occasional  instances  does  it  extend  into  the  right  hypochondrium. 

The  cardiac  orifice  is  found  behind  the  seventh  left  costal  cartilage, 
L'.")  cm.  I  in. )  from  the  median  line,  to  the  left  side  of  the  tenth  or  eleventh 
thoracic  vertebra  (ninth  or  tenth  thoracic  spine), and  11  cm.  (4^ in.)  from 
the  anterior  belly  wall.  It  descends  about  2.5  cm.  (1  in.)  in  forced  inspi- 
ration.  Occasionally  the  cardiac  orifice  is  found  in  the  median  line  or 
even  somewhat  to  the  right  of  it.  I  have  found  it  in  this  position  in  a 
I  ga  trostomy  for  esophageal  stenosis,  and  other  cases  are  reported. 
This  orifice  is  nearer  the  anterior  than  the  posterior  surface  of  the  stomach 
by  one-third  of  its  anteroposterior  diameter.  It  is  distant  39  to  40  cm. 
I.V,  to  16  in.  I  from  the  incisor  teeth. 

The  fundus  extends  '.',  lo  5  cm.  (I{  <«»  2  in.)  higher  than  the  cardiac 
orifice  and   it>  upper  limit  corresponds  to  the  level  of  the  sixth  left  chon- 

drosternal  joint,  to  thai  of  the  eighth  intercostal  space  in  the  scapular 
line,  and  i"  the  ninth  or  tenth  thoracic  vertebra.  Its  highest  />"/•/  lies 
directly  beneath  the  left  dome  of  the  diaphragm,  behind  and  above  the 

l.eal  of  the  heart       ita  close  relation  to  (he  Icl'l  lung  and  the  hciit 

explains  the  interference  with  their  function  when  the  .stomach  is  dis- 
tended, as  with  flatulence,  which  causes  shortness  of  breath  and  palpi- 
tation of  the  heart    Many  imagine  they  have  heart  disease  when  the 


326  THE  ABDOMEN 

real  trouble  is  indigestion.  Owing  to  the  position  of  the  fundus  the 
stomach  is  sometimes  wounded  in  wounds  of  the  lower  part  of  the 
pleural  cavity  involving  the  diaphragm. 

The  great  curvature  in  its  upper  or  left  part  is  covered  by  the  diaphragm, 
which  separates  it  from  the  lung,  the  sinus  of  the  pleura,  and  the  thorax 
as  we  follow  it  from  above  downward.  It  crosses  the  left  costal  margin 
about  the  junction  of  the  ninth  and  tenth  costal  cartilages.  Inferiorly 
it  extends  to  a  point  2  to  4  cm.  (f  to  1^  in.)  or  two  fingers'  breadth  above 
the  umbilicus,  and  further  to  the  right  it  ascends  along  the  median  edge 
of  the  gall-bladder.  A  normal  stomach  fully  distended  may  even  reach 
to  the  umbilicus,  and  in  cases  of  gastrectasis,  or  dilatation  of  the  stomach, 
the  great  curvature  may  reach  any  level  between  its  normal  position 
and  the  symphysis.  This  condition  is  due  to  an  obstruction  at  the 
pylorus  from  cancerous  newgrowth,  cicatricial  stenosis  following  an  ulcer, 
thickening  of  the  circular  muscle  of  the  pylorus  in  some  forms  of  dyspep- 
sia with  hyperacidity  and  spasm  of  the  pylorus,  the  pressure  of  an  ex- 
trinsic tumor,  etc.  The  enlargement  can  be  readily  made  out  by  inspec- 
tion, palpation,  and  percussion  after  distending  the  stomach  with  air,  by  a 
bicycle  pump  attached  to  a  stomach  tube.  The  great  curvature  may  also 
reach  a  low  level  in  gastroptosis,  in  which  the  entire  stomach  is  displaced 
downward  owing  to  the  lengthening  of  the  lesser  omentum  and  the  other 
supports  of  the  stomach.  It  is  favored  by  the  use  of  corsets.  This  con- 
dition is,  not  unlikely,  at  times  more  of  a  vertical  enlargement  (without 
the  transverse)  than  a  displacement.  The  stomach  may  be  somewhat 
pulled  down  by  the  traction  of  the  omentum  adherent  to  the  sac  of  a 
hernia. 

On  the  other  hand,  when  it  is  entirely  empty,  as  in  cases  of  stricture  of 
the  esophagus,  the  stomach  is  high  up  under  the  left  lobe  of  the  liver 
and  the  costal  cartilages  and  far  back  in  the  abdomen,  so  that  the  trans- 
verse colon  projects  up  in  front  of  it  from  below  and  (according  to 
Sedillot)  the  anterior  border  of  the  spleen  overlaps  it  from  the  side.  In 
such  cases  it  may  be  hard  to  find,  but  this  can  be  done  (1)  by  following  up 
the  under  surface  of  the  liver  to  the  small  omentum,  and  down  the  latter 
to  the  stomach,  or  (2)  by  pulling  down  the  omentum  and  following  it  up 
to  the  stomach  over  the  colon,  which  we  distinguish  by  the  longitudinal 
bands  and  the  appendices  epiploicae.  On  account  of  its  position  the 
stomach  is  much  less  exposed  to  injury  when  empty,  and  the  injury  is 
less  dangerous  because  there  is  little  extravasation  of  its  contents. 

The  lesser  curvature  lies  under  cover  of  the  left  lobe  of  the  liver  except 
in  cases  of  gastroptosis,  when  it  is  displaced  below  it.  It  descends  nearly 
vertically  in  front  of  the  left  cms  of  the  diaphragm  and  the  left  side  of  the 
last  two  thoracic  vertebrae,  from  the  esophageal  orifice  to  the  antrum, 
where  it  turns  quite  sharply  and  passes  transversely  to  the  right,  at  the 
level  of  the  first  lumbar  vertebra,  and  then  slightly  upward  to  the  pylorus. 
Three-fourths  or  four-fifths  of  the  stomach  lie  to  the  left  of  the  median 
line. 

The  pylorus  is  covered  by  the  quadrate  lobe  of  the  liver  3  to  4  cm. 
(1^-  to  If  in.)  to  the  right  of  the  median  line  and  7  cm.  (2f  in.)  lower  than 


THE  ABDOMINAL   VISCERA  327 

the  cardiac  orifice  or  the  stemoxiphoid  articulation.  It  is  more  mobile 
laterally  than  vertically,  and  its  radius  of  mobility  is  2  to  3  cm.  (f  to 
1^  in.).  It  lies  near  the  median  line,  in  line  with  the  right  border  of  the 
sternum  when  the  stomach  is  empty;  farther  to  the  right  (7.5  cm.  [3  in.] 
according  to  Braune)  when  it  is  full.  In  general  it  corresponds  to  a  point 
near  the  end  of  the  eighth  right  costal  cartilage,  to  the  level  of  a  line 
drawn  between  the  bony  ends  of  the  seventh  ribs  in  front,  and  to  the 
upper  border  of  the  first  lumbar  vertebra  (or  the  twelfth  thoracic  spine) 
behind.  The  difficulty  of  palpating  tumors  of  the  pylorus  is  explained 
by  its  being  covered  by  the  liver,  except  occasionally  when  it  is  displaced 
downward  bv  the  newgrowth  before  the  latter  becomes  adherent  above. 
AY  hen  the  stomach  is  distended  the  antrum  may  extend  farther  to  the 
right  than  the  pylorus  itself. 

The  axis  of  the  stomach  is  now  generally  considered  more  vertical  than 
formerly  supposed,  especially  that  of  the  cardiac  portion.  This  fact, 
perhaps,  combined  with  more  or  less  gastroptosis  or  gastrectasis,  accounts 
for  the  sword-swallowing  feats.  Good  authorities,  however,  claim  that 
it  is  more  horizontal,  especially  in  the  empty  stomach,  passing  from  behind 
at  the  summit  of  the  fundus  forward  to  the  right  and  slightly  downward, 
while  in  the  distended  state  the  axis  is  more  oblique  (45  degrees)  (Bir- 
mingham). The  axis  of  the  stomach  is  sometimes  more  vertical  in  infants, 
retaining  some  of  the  vertical  position  of  the  embryo,  and  exceptionally 
it  remains  so  in  the  adult. 

The  anterior  surface  of  the  stomach  is  in  contact  with  the  diaphragm 
and  the  anterior  thoracic  wall,  which  covers  the  fundus;  to  the  right  of 
this,  with  the  liver  above  and  the  abdominal  wall  below.  The  liver 
covers  the  pylorus  and  the  parts  just  below  the  lesser  curvature,  and 
leaves  a  more  or  less  triangular  area  where  the  stomach  is  in  contact  with 
the  abdominal  wall.  This  triangle  is  bounded  on  the  left  by  the  eighth 
and  ninth  costal  cartilages;  on  the  right  by  the  free  margin  of  the  liver, 
passing  from  the  ninth  right  to  the  eighth  left  costal  cartilage;  and  below 
by  the  transverse  colon,  or  a  line  joining  the  tips  of  the  tenth  costal 
cartilages.  The  latter  has  a  distinct  tip  which,  when  pressed  over  the 
ninth  cartilage,  gives  a  peculiar  crepitus  to  the  finger. 

Through  this  triangle  we  reach  the  stomach  in  the  various  operations 
on  that  viscus.  The  incision  may  extend  above  the  right  border  of  the 
triangle,  for  the  free  margin  of  the  liver  can  be  retracted  upward.  The 
line  of  incision  may  be  vertical,  in  the  median  or  semilunar  lines  or 
through  the  rectus  muscle,  or  oblique,  parallel  with  and  2.5  em.  (1  in.) 
from  the  left  costal  margin.  In  the  latter  case  the  part  of  the  incision 
inal  to  the  rectus  divides  the  three  flat  abdominal  muscles.  Behind 
the  rectus  we  meet  with  the  superior  epigastric  artery,  which  we  avoid 
or  ligate.  Of  these  operations  the  most  important  are  gastrotomy, 
gastrostomy,  gastroenterostomy,  pyloroplasty,  and  pylorectomy. 

In  gastrotomy  the  stomach  is  opened  anteriorly  to  remove  foreign 
bodies,  to  treat  a  stricture  of  the  esophagus  by  retrograde  dilatation,  or 
toe  exploration. 

In  gastrostomy  ;i  gastric  fistula  is  established  in  order  to  \'cr<]  the  patient 


328 


THE  ABDOMEN 


when  there  is  a  cancerous  stricture  of  the  esophagus.  The  many  recent 
modifications  of  the  technique  of  gastrostomy  have  aimed  at  preventing 
leakage  of  the  stomach  contents.  This  is  more  or  less  perfectly  secured 
in  Witzel's  method  by  suturing  the  stomach  wall  over  the  tube  for  5  cm. 
or  so  from  the  opening,  and  thus  making  a  long  oblique  fistula  surrounded 
by  the  muscle  of  the  stomach  wall;  in  Kader's  and  Senn's  method,  by 
inverting  over  a  tube  a  small  cone  of  the  stomach  wall  as  a  valve,  etc. 

In  gastroenterostomy  an  anastomosis  is  made  between  a  low  point  in  the 
stomach  and  the  upper  part  of  the  jejunum,  7.5  to  10  cm.  (3  to  4  in.)  or 

Fig.  110 


Showing  the  blood  supply  of  the  stomach,  the  vein  indicating  the  position  of  the  pylorus, 
the  gall-bladder,  cystic  duct  and  artery,  and  the  common  bile  duct.  A  chronic  ulcer  is  repre- 
sented at  the  pylorus  and  the  dotted  lines  indicate  the  incisions  for  its  removal.  The  small 
omentum  has  been  removed.      (Mayo.) 

less,  from  its  commencement,  when  the  outlet  of  the  stomach  is  obstructed 
and  in  cases  of  chronic  gastric  hemorrhage  and  intractable  pain  from 
ulcer.  Though  formerly  done  through  the  anterior  stomach  wall,  it  is  now 
most  often  done  through  the  posterior  wall.  If  the  anastomosis  occupies 
the  most  dependent  position  it  was  thought  to  make  little  difference 
whether  the  anterior  or  posterior  method  is  used.  But  the  posterior 
method  has  the  great  advantage  of  allowing  a  short  loop  of  7.5  cm.  (3  in.) 
of  the  jejunum  to  be  used,  the  so-called  "  no-loop"  method.   The  loop  is 


THE  ABDOMINAL  VISCERA 


329 


now  thought  responsible  for  the  chronic  biliary  regurgitation  and  vomit- 
ing which  occasionally  complicates  the  after-course  in  these  cases,  and 
the  anterior  method  requires  a  loop  of  40  to  50  cm.  (16  to  20  in.).  Also 
the  straight  drop  of  the  boWel  from  the  anastomosis  gives  protection 
against  secondary  jejunal  ulcer  by  the  constant  presence  of  the  alkaline 
secretions  (Mayo).  The  posterior  wall  is  reached  through  an  opening 
in  the  avascular  area  of  the  transverse  mesocolon.  This  area  lies  to  the 
left  of  the  peritoneal  band  which  passes  to  the  commencement  of  the 
jejunum  from  the  transverse  mesocolon.  This  band  arises  from  the 
latter  close  to  the  left  of  a  branch  of  the  middle  colic  artery  which  comes 
forward  on  the  right  of  the  duodenojejunal  junction.  The  clamp  and 
suture  method  is  the  one  row  most  generally  employed.  When  done  for 
non-malignant  conditions  the  good  results  are  permanent. 


Fig.  Ill 


Posterior  relations  of  the  stomach.      (Testut.) 

Pyloroplasty  is  employed  in  some  cases  of  pyloric  stenosis,  and  the 
pyloric  opening  is  enlarged  by  suturing  a  longitudinal  incision  in  a  trans- 
verse direction.  In  gastroduodenostomy  (Finney's  operation)  a  horse- 
shoe-shaped opening  in  the  pylorus  and  duodenum  is  sutured  so  as  to 
make  a  large  opening,  in  place  of  a  pyloroplasty. 

In  pylorectomy  or  gastrectomy,  first  employed  by  Billroth,  a  large  part 
or  the  whole  of  the  stomach  is  removed  for  gastric  cancer  and  occa- 
sionally for  ulcer.  Owing  to  the  course  of  the  lymph  circulation  nearly 
the  entire   lesser  curvature  is  removed,  up  to  the   point  where   the  eor- 

onary  artery  meets  if.  Prom  hen-  the  line  of  section  of  the  stomach, 
in  pyloric  carcinoma,  is  downward  and  to  the  right,  so  that  less  of  the 
greater  curvature  is  removed.  The  object  of  this  is  to  remove  the  dis- 
eased lymphatics,  its  well  as  the  newgrowth,  in  cases  where  a  cancer  of  the 
pyloric  end  of  the  stomach  is  removable.  The  large  opening  left  after 
ction  of  the  tumor  is  closed  and  a  gastroenterostomy  added. 


330  THE  ABDOMEN 

How  is  the  Stomach  Held  in  Position? — The  stomach  is  attached  only 
at  the  cardia;  the  pylorus  is  fastened  to  the  posterior  abdominal  wall 
through  its  connection  with  the  duodenum.  The  stomach  is  also  sup- 
ported by  the  gastrophrenic  ligament  from  the  diaphragm,  to  the  left  of 
the  esophagus,  and  by  the  lesser  omentum  from  the  transverse  fissure 
of  the  liver.  The  thickened  right  border  of  this  omentum  extends  onto 
the  first  part  of  the  duodenum  as  the  hepatoduodenal  ligament  and 
helps  to  support  the  pylorus.  The  cardia  and  pylorus  are  the  most  fixed 
points,  and  the  lesser  curvature,  attached  at  either  end  to  these  fixed 
points,  cannot  change  its  relative  position  to  any  extent,  hence  it  is  the 
more  fixed  border  of  the  stomach.  It  moves  slightly  with  respiration. 
In  the  gradual  distention  of  the  stomach  the  fundus  ascends  upward  and 
backward  into  the  left  cupola  of  the  diaphragm,  and  the  lower  part  of 
the  stomach,  as  it  descends,  is  pressed  forward  by  the  direction  of  the 
"stomach  bed"  or  floor  and  the  relation  of  the  surrounding  structures. 
This  brings  the  greater  curvature  upward  and  forward  without  any  dis- 
tinct rotation  of  the  organ  on  its  long  axis.  When  full  the  stomach  rests 
below  upon  the  transverse  colon  and  mesocolon,  so  that  the  latter  and 
the  hepatocolic  and  phrenocolic  ligaments,  which  help  to  support  the 
colon,  assist  in  supporting  the  stomach.  The  stomach  is  not  supported 
by  intra-abdominal  pressure. 

The  stomach  is  also  connected  with  other  structures.  At  the  great 
curvature  the  peritoneum  covering  the  front  and  back  surfaces  of  the 
stomach  meet  and  pass  down  as  the  great  omentum.  This  is  the  original 
mesentery  of  the  stomach.  Its  left  extremity,  the  gastrosplenic  omentum, 
connects  the  stomach  with  the  spleen  and  inferiorly  the  portion  known 
as  the  gastrocolic  ligament  connects  the  stomach  with  the  transverse 
colon. 

Other  Relations  of  the  Stomach. — The  posterior  surface  of  the  stomach 
rests  in  great  part  on  the  transverse  mesocolon,  above  this  on  the  pancreas, 
with  the  splenic  vessels  along  its  upper  border,  more  to  the  left  on  the 
splenic  flexure  of  the  colon,  the  upper  half  of  the  left  kidney,  the  entire 
left  suprarenal  capsule,  and  the  anterior  surface  of  the  spleen.  This  is 
called  the  "stomach  bed,"  and  it  slopes  from  above  downward  and  for- 
ward. In  addition,  the  crura  of  the  diaphragm,  the  aorta,  the  vena  cava 
inferior,  the  fourth  portion  of  the  duodenum,  and  the  solar  plexus  also  lie 
behind  the  stomach.  Between  the  pancreas,  kidney,  and  suprarenal 
capsule  behind,  and  the  stomach  in  front  lies  the  lesser  peritoneal  sac. 
Perforating  ulcers  of  the  posterior  wall  of  the  stomach  may  open  into  this 
sac  or,  after  adhesion,  into  one  of  the  viscera  named  as  lying  behind  it, 
causing  perhaps  an  abscess  of  the  organ  so  invaded.  Cases  are  recorded 
where  such  ulcers  have  given  rise  to  ulceration  of  the  splenic  artery, 
causing  a  fatal  hemorrhage  into  the  stomach.  On  cross-section  of  the 
abdomen  the  stomach  is  seen  to  lie  between  the  liver  and  the  spleen,  so 
that  it  may  be  displaced  by  enlargements  of  either  of  these  organs. 

Layers  of  the  Stomach  Wall. — Peritoneum  covers  the  entire  stomach 
except  for  a  narrow  strip  along  the  lesser  and  greater  curvatures,  where 
the  anterior  and  posterior  layers  are  continuous  with  the  small  and  great 


THE  ABDOMINAL  VISCERA  331 

omenta  respectively,  and  where  the  vascular  trunks  run.  This  serous 
layer  is  closely  bound  by  a  scanty  subserous  tissue  to  the  thick  muscular 
layer.  Only  in  a  distended  stomach  does  the  peritoneum  retract  some- 
what on  incision.  The  muscular  tissue  is  quite  thick,  so  that  in  suturing 
there  is  more  for  the  sutures  to  hold  to  and  less  danger  of  the  needle  pene- 
trating all  the  coats  than  in  intestinal  suture.  Owing  to  the  difference  in 
direction  of  the  fibers  of  the  three  layers,  and  of  the  line  of  their  retraction 
on  division,  gastric  wounds  are  ragged  and  not  likely  to  gape.  If  small, 
they  may  be  quite  effectually  plugged  by  the  protrusion  of  the  mucous 
membrane,  which  is  permitted  by  the  looseness  of  the  submucous  tissue. 
The  latter  also  allows  the  non-elastic  mucous  membrane  in  an  actively 
contracted  stomach  to  form  prominent  longitudinal  folds,  more  marked 
toward  the  pyloric  end  and  along  the  great  curvature,  which  greatly 
reduce  its  lumen.  The  folds  may  partly  or  wholly  disappear  when  the 
stomach  is  relaxed.  There  is  a  zigzag  Hue  encircling  the  cardiac  orifice 
on  its  inner  surface  opposite  the  tenth  thoracic  vertebra,  where  the 
thick  columnar  epithelium  of  the  gastric  mucosa  joins  the  thinner 
squamous  epithelium  of  the  esophageal  mucosa. 

Vessels. — The  arteries,  derived  from  the  gastric,  hepatic,  and  splenic 
branches  of  the  celiac  axis,  run  along  both  curvatures  of  the  stomach 
and  from  both  ends,  anastomosing  where  they  meet.  Branches  pass 
from  these  trunk  vessels,  at  right  angles  to  the  trunks  and  to  the  axis 
of  the  stomach,  over  both  surfaces  where  they  anastomose  on  meeting. 
The  veins  take  the  same  course.  Hence  an  incision  parallel  with  and  near 
the  curvatures  divides  many  of  these  branches  where  they  are  largest,  and 
considerable  hemorrhage  results.  Near  the  curvatures  incisions  at  right 
angles  to  them  (i.  e.,  parallel  with  the  vessels)  cause  less  bleeding,  while 
midway  between  the  curvatures  incisions  parallel  with  them  occasion 
but  little  hemorrhage.  As  the  blood  supply  is  from  three  sources,  and  the 
anastomoses  are  numerous,  the  nutrition  of  the  wound  edges,  even  after 
extensive  resections  is  well  maintained,  as  a  rule.  If  the  larger  trunk 
jels  are  concerned  in  a  gastric  ulcer  and  become  adherent  to  the  stom- 
ach wall  and  finally  eroded,  serious  hemorrhage  into  the  stomach  may 
result.  The  veins  empty  into  the  portal  vein  either  directly  or  through 
the  splenic  and  superior  mesenteric.  Hence  the  varicose  gastric  veins 
and  the  congestion  of  the  stomach  with  hemorrhage  into  it,  in  cirrhosis  of 
the  liver,  or  cardiac  disease  accompanied  by  portal  obstruction.  At  the 
cardiac  orifice  the  gastric  veins  anastomose  with  the  esophageal  veins 
which  empty  into  the  superior  cava. 

The  Lymphatics  of  the  Stomach.  There  are  three  distinct  lymphatic 
territories  of  the  stomach:  (1)  Along  the  lesser  curvature  and  the  two- 
thirds  of  both  surfaces  adjacent  to  i( ;  (2)  the  remaining  surface  on  either 
side  of  the  greater  curvature  al  the  pyloric  end;  (.'>)  a  similar  strip  along 

the  vertieal  portion  of  this  curvature  /.  <■.,  the  fundus.       From  (I)  lymph 

■  I  pa  to  nodes  along  the  lesser  curvature,  grouped  principally  near 
the  spot  where  the  coronary  vessels  approach  this  border;  from  (2)  they 
pa  to  '■'•  to  6  nodes  between  the  layers  of  the  great  omentum,  beneath  the 
pyloric  portion  of  the  stomach,  and  2  or  '->  nodes  behind  the  pylorus  and 


332  THE  ABDOMEN 

in  front  of  the  pancreas;  from  (3)  they  pass  to  nodes  along  the  splenic 
artery.  Districts  1  and  2  are  the  most  important.  They  drain  the  pyloric 
end  where  cancer  occurs.  The  position  of  glands  of  district  1  direct  the 
course  of  the  incision  in  gastrectomy  (p.  329). 

Nerves. — The  anterior  and  'posterior  gastric  plexuses,  formed  by  the 
left  and  right  pneumogastric  nerves  respectively,  together  with  sympa- 
thetic branches  from  the  solar  plexus,  lie  near  the  lesser  curvature  at  its 
cardiac  end.  The  abundant  nerve  supply  accounts  for  the  severe  pain  of 
ulcer  and  the  collapse  caused  by  injury.  When  the  pylorus  is  adherent 
and  is  much  dragged  upon  during  operation  severe  shock  may  be  observed, 
due  to  the  disturbance  of  the  large  sympathetic  nerves  and  plexuses 
behind  it.  The  relation  of  the  sympathetic  nerves  of  the  stomach  with 
the  seventh  to  ninth  spinal  nerves  accounts  for  the  epigastric  tenderness 
and  the  reflected  left  shoulder-blade  pain  in  gastric  ulcer,  etc.  It  will 
be  noticed  that  the  plexuses  are  along  and  near  the  lesser  curvature, 
especially  at  its  cardiac  end,  explaining  the  reflex  palpitation  of  the  heart, 
faintness,  or  asthma  which  may  occur  after  going  to  bed  with  the  stomach 
full  of  an  undigested  meal,  which  then  presses  against  the  lesser  curva- 
ture and  irritates  the  nerves.  After  vomiting  the  attack  subsides.  Irri- 
tation of  the  gastric  pneumogastric  filaments  may  be  misinterpreted  by 
the  brain  as  an  irritation  of  the  pulmonary  fibers  and  give  rise  to  a 
"stomach  cough."  Irritation  of  the  pneumogastric  filaments  in  the  neck, 
brain,  or  stomach  (from  disease,  concussion,  or  in  a  sea  voyage)  may 
cause  vomiting. 

Congenital  Malformations. — Congenital  malformations  of  the  stomach 
are  rare.  It  may  be  displaced  in  cases  of  transposition  of  the  viscera  and 
of  congenital  deficiencies  of  the  diaphragm  or  anterior  body  wall.  Com- 
plete congenital  atresia  of  the  pylorus  is  very  rare;  stenosis  of  the  pylorus 
is  more  common.  In  certain  rare  cases  an  hourglass  stomach  is  prob- 
ably of  congenital  origin,  in  most  cases  it  is  due  to  cicatricial  contraction 
following  ulcer  or  corrosive  poison,  and  it  is  very  much  more  common  in 
females  than  in  males. 

The  pathological  conditions  affecting  the  anatomy  of  the  stomach  are 
chiefly  ulcer  and  cancer.  Ulcer  occurs  along  the  lesser  curvature  in  36  per 
cent.;  on  the  posterior  wall  in  25  per  cent.;  at  the  pylorus  in  15.6  per 
cent.1  Among  chronic  ulcers  75  per  cent,  are  in  the  pyloric  region.  The 
acute  round  ulcer  is  more  evenly  distributed.  Ulceration  of  the  distal 
18  mm.  (f  in.)  (the  canal  of  Jonnesco)  is  not  common.  Occurring  so 
often  on  the  lesser  curvature,  pain  does  not  come  on  so  immediately 
after  eating  a  meal  as  in  case  of  gastric  catarrh,  where  the  great  curva- 
ture is  chiefly  involved,  for  pain  occurs  only  when  the  food  is  in  contact 
with  the  ulcer,  hence  vomiting  brings  relief.  Chronic  gastric  ulcer  is 
usually  single,  but  in  perhaps  half  the  cases  of  acute  ulcer  more  than 
one  is  present.  Chronic  ulcer  is  not  infrequently  saddle-shaped,  involv- 
ing both  surfaces  and  the  curvature  between  them.  Acute  ulcer  occurs 
more  commonly  in  women,  chronic  ulcer  in  men.     Perforation  of  the 

1  Fenwick's  analysis  of  1015  cases. 


THE  ABDOMINAL  VISCERA  333 

stomach  is  liable  to  occur  in  both  forms,  but  more  frequently  in  acute 
ulcer.  If  adhesions  take  place,  the  perforation  may  be  closed  or  a  cir- 
cumscribed abscess  formed,  otherwise  a  general  peritonitis  ensues.  The 
cicatricial  contraction  following  an  ulcer  at  the  pylorus  narrows  the 
orifice  and  causes  pyloric  obstruction.  This  causes  at  first  an  hyper- 
trophy of  the  stomach,  to  overcome  the  obstruction,  but  later  on  this 
gives  place  to  dilatation  and  its  sequela?.  An  hourglass  stomach  may 
result  from  the  cicatricial  contraction  if  the  ulcer  occurs  in  the  body  of 
the  stomach.  Adhesions  to  contiguous  viscera  may  cause  violent  gas- 
tralgia  owing  to  the  traction  on  the  stomach.  Cancer  of  the  stomach 
affects  the  pylorus  in  60  or  more  per  cent,  of  the  cases,  where  sooner 

Fig.  112 


CORONARY    ARTERY 
CORONARY      VEIN 


HEPATIC     ARTERY 


GASTRO-EPIPLOIC 
ARTERY 


GANGLION 

GASTRO-EPIPLOIC 

VEIN 


Showing  :in:it< >rny  of  the  stomach,  with  especial  reference  <o  the  distribution  of  the 
lymphatics.      (Mayo,  after  Cuneo.) 

or  later  it  usually  obstructs  the  outlet  with  the  resulting  sequelae.  In 
a  considerable  proportion  of  cases  the  cancer  has  its  origin  in  a  chronic 
ulcer.  Lymphatic  infection  is  said  to  be  less  frequent  and  less  rapid 
than  in  cancer  elsewhere,  occurring  in  only  about  50  per  cent,  of  eases 
(Sutton  .  Palpation  of  the  tumor  in  its  early  stages  is  unsatisfactory  on 
account  of  its  depth  and  the  liver  and  other  structures  which  overlie  it. 
In  diaphragmatic  hernia  I  have  seen  the  stomach  in   the  lefl  pleural 

cavity,  and   many  such  cases  are  recorded.     A  part  of  (he  stomach  may 

occa  ionally  be  found  in  an  umbilical  hernia.     Exceptionally  the  stomach 

iii-*-.   be  ruptwed  by  a  Contusion.     There  is  more  danger  of  this  when  the 
tomacfa  i     lull,  and  hence  in  closer  contact  with  the  abdominal  wall. 


334 


THE  ABDOMEN 


Vomiting  is  effected  by  the  abdominal  muscles  compressing  the  stomach 
against  the  liver  and  diaphragm.  The  latter  is  depressed  to  its  lowest 
level  by  a  full  inspiration  and  fixed  by  the  closure  of  the  glottis,  so  that  a 
patient  with  an  opening  in  the  trachea  cannot  vomit.  As  vomiting  is 
naturally  easier  with  a  full  stomach,  plenty  of  warm  water  should  be  given 
with  an  emetic.  Eructation  is  accomplished  by  the  muscular  action  of  the 
stomach  alone. 

The  Small  Intestine. — The  small  intestine,  extending  between  the 
pyloric  and  ileocecal  valves,  averages  in  length  in  the  adult,  independently 
of  height,  weight,  or  age,  675  cm.  (22^  ft.)  in  the  male  and  700  cm. 
(23-^  ft.)  in  the  female  (Treves).  In  the  infant  at  birth  it  averages  285 
cm.  (9^  ft.).  The  diameter  and  the  thickness  and  vascularity  of  the  wall 
decrease  from  its  upper  to  its  lower  end,  the  former  from  5  to  3.5  cm. 
(2  to  1^  in.)  in  the  duodenum  to  3  cm.  (1^  in.)  in  the  lower  ileum. 


Fig.  113 


CORONARY 
CURRENT 


RIGHT 

GASTRO-EPIPLOIC 

CURRENT 


SPLENIC 
'-*■  CURRENT 


Lymphatic  areas  of  the  stomach.      (Cuneo.) 

The  Duodenum  (Figs.  109,  110,  115,  121  to  123,  and  126).— The  duod- 
enum or  first  portion  is  the  only  part  having  a  fixed  position  or  extent, 
25  to  30  cm.  (10  to  12  in.).  It  lies  in  great  part  retroperitoneally.  In 
shape  it  forms  a  kind  of  spiral,  within  which  is  the  head  of  the  pan- 
creas. Its  natural  division  into  three  or  four  parts  is  useful  in  studying 
its  relations. 

The  first  part  (or  superior  longitudinal  portion)  is  about  5  cm.  (2  in.) 
long,  and  is  the  most  movable  part  on  account  of  its  peritoneal  relations. 
Its  entire  anterior  surface  and  the  first  2.5  cm.  (1  in.)  or  so  of  its  posterior 
surface,  next  to  the  pylorus,  are  covered  by  peritoneum  continuous  with 
that  of  the  stomach  and  of  the  right  end  of  the  lesser  omentum,  known 
as  the  ligamentum  hepatoduodenale.  Thus  this  portion  of  the  duodenum 
is  allowed  to  follow  the  movements  of  the  stomach,  and  so  avoid  undue 
traction.  The  direction  of  this  segment  is  nearly  horizontal  and  varies 
with  the  fulness  of  the  stomach.  When  the  stomach  is  distended  and  the 
pylorus  is  pushed  over  to  the  right  it  passes  nearly  directly  backward. 
When  the  stomach  is  empty  its  course  is  nearly  transverse  from  left  to 
right,  with   only  a   slight   inclination   backward,    and    between**' [these 


THE  ABDOMINAL  VISCERA 


335 


extremes  its  direction  varies  according  to  the  condition  of  the  stomach. 
Its  distal  end  is  fixed  at  the  level  of  the  first  lumbar  vertebra,  under  the 
right  lobe  of  the  liver,  or  the  neck  of  the  gall-bladder,  so  that  it  is  found 
stained  by  bile  postmortem.  It  forms  the  lower  boundary  of  the  foramen 
of  Winslow.  The  common  bile  duct,  the  vena  porta?,  and  the  gastro- 
duodenal  artery  pass  behind  it;  the  head  of  the  pancreas  lies  below  it. 

Behind  the  neck  of  the  gall-bladder  it  bends  downward  into  the 
second  part,  which  descends  for  nearly  7.5  cm.  (3  in.)  to  the  right  of  the 
first,  second,  and  third  lumbar  vertebra?  and  in  front  of  the  vena  cava,  the 
renal  vessels,  and  the  inner  c(\^e  of  the  right  kidney.  These  relations  are 
to  be  borne  in  mind  in  operations  on  the  right  kidney.  About  its  middle 
it  is  crossed  in  front  by  the  attachment  of  the  two  layers  of  the  transverse 
mesocolon,  between  which  it  is  entirely  bare  of  peritoneum  and  nearly 
in  contact  with  the  right  end  of  the  transverse  colon.    The  parts  of  the 


RIGHT  SUPRARENAL 
CAPSULE 


Fig.  114 


LEFT  SUPRARENAL 
CAPSULE 


LINE   OF  REFLECTION 
OF   MESOCOLON 


LINE    OF    REFLECTION 
OF    MESENTERY 


DUODENOJEJUNAL 
JUNCTION 


Abdominal  viscera  from  in  front,  after  His'  models. 


second  portion  above  and  below  the  mesocolon  are  covered  with  peri- 
toneum iii  front  only.  This  peritoneum  is  continuous,  above  the  meso- 
colon, with  the  upper  layer  of  the  hitter,  laterally  with  that  covering  the 
front  of  the  right  kidney,  and  mesially  with  the  gastrocolic  ligament. 
Below  the  mesocolon  the  peritoneum  is  continuous  with  its  inferior 

layer. 

The  mpracolic  pur/ion  is  in  contact  with  the  under  surface  of  the  right 
lobe  of  the  liver,  on  which  it  forms  an  impression  (impressio  duodenalis) 
to  the  righl  of  the  neek  of  the  gall-bladder.  The  relation  of  the  supra- 
colic  portion  of  the  duodenum  to  the  gall-bladder,  iii  front  of  it,  explains 
how  gallstones  may  ulcerate  through  the  latter  into  the  former,  and  how 
the  two  may  he  anastomosed  (cholecystenterostomy)  to  form  an  outlet 
for  the  bile  in  irremovable  obstruction  of  the  common  duct.  To  the  left  of 
it  li<-   the  Ik  ;nl  of  tin-  pancreas,  which  sometimes  overlaps  it  in  front,  and 


336  THE  ABDOMEN 

between  the  two  are  the  pancreaticoduodenal  artery  in  front,  and  the 
common  bile  duct  behind.  It  is  bound  to  parts  behind  it  by  areolar 
tissue,  which  renders  easy  its  separation  from  them  and  allows  of  some 
change  in  position  of  the  duodenum  in  the  transverse  direction.  Thus 
by  incising  the  peritoneum  on  the  right  side  of  the  supracolic  portion 
we  may  raise  up  this  part  and  displace  it  to  the  left,  so  as  to  reach  the 
lower  end  of  the  common  bile  duct,  or  mobilize  it,  so  as  to  allow  the  easy 
performance  of  gastroduodenostomy  (Finney,  Kocher).  Downward 
shifting  is  entirely  prevented  by  the  fixation  of  the  first  part  by  the 
hepatoduodenal  ligament,  and  in  this  way  any  traction  on  the  pancre- 
atic and  common  bile  ducts  and  the  resulting  functional  disturbances 
are  prevented. 

The  supracolic  portion  and  the  first  part  of  the  duodenum  are  exposed 
between  the  liver  and  the  transverse  colon  by  pulling  the  former  up  and 
the  latter  down,  retracting  the  stomach  to  the  left,  and  following  the 
pylorus  to  the  right.  Sometimes,  on  account  of  a  high  position  of  the 
transverse  colon  and  mesocolon,  but  little  of  the  duodenum  is  to  be  found 
above  them.  The  common  bile  duct,  usually  in  common  with  the  pan- 
creatic duct,  enters  the  duodenum  at  the  end  of  a  papilla  on  the  inner 
and  dorsal  aspect  of  the  second  portion,  about  7.5  to  10  cm.  (3  to  4  in.) 
from  the  pylorus.  On  the  interior  of  the  duodenum,  at  the  junction  of  the 
first  and  second  portions,  is  a  crescentic  fold  of  mucous  membrane,  on  the 
inner  and  posterior  aspect.  According  to  Brewer,  this  fold  is  permanent, 
is  made  prominent  by  pulling  the  bend  upward,  averages  47  mm.  (1.9  in.) 
from  the  pyloric  valve  and  35  mm.  (1.4  in.)  from  the  papilla,  and  may  be 
useful  in  finding  the  latter. 

The  second  portion  of  the  duodenum  is  sometimes  opened  in  front  to 
remove  a  stone  impacted  in  the  ampulla  of  Vater  (see  p.  372).  Ochsner 
has  called  attention  to  a  marked  thickening  of  the  circular  fibers  2  to 
4  cm.  below  the  papilla,  whose  contraction  narrows  this  portion  and  may 
cause  a  distention  of  the  parts  above  and  the  regurgitation  of  bile 
into  the  stomach.  Physiologically  it  may  provide  for  the  thorough  mixing 
of  the  chyme  with  the  biliary  and  pancreatic  secretions. 

Ulcer  of  the  duodenum  was  formerly  thought  to  be  uncommon,  but 
among  200  cases  operated  upon,  98  were  of  the  duodenum,  87  of  the  stom- 
ach, and  15  of  both  (Mayo).  They  occur  mainly  in  the  first  4  cm.  (1-|  in.) 
of  the  duodenum  and  altogether  above  the  bile  papilla,  i.  e.,  in  the  area 
where  the  contents  are  acid.  In  most  cases  they  are  on  the  anterior  wall 
and  extend  up  to  or  near  the  pylorus.  They  occur  more  often  in  males, 
in  the  ratio  of  3  to  1.  Perforation  is  not  infrequent,  and  is  not  rare 
without  previous  symptoms.  Severe  hemorrhage  may  complicate  these 
cases.  Cicatrization  may  result  in  stricture.  JBrunner's  glands,  which 
are  said  to  be  the  seat  of  the  uncommon  ulceration  in  cases  of  burns,  are 
mostly  in  the  upper  part  of  the  duodenum,  and  perforation  of  such  ulcers 
is  apt  to  be  intraperitoneal. 

The  third  or  transverse  portion  of  the  duodenum,  nearly  12.5  cm.  (5  in.) 
long,  extends  from  the  right  side  of  the  third  lumbar  vertebra  across  the 
latter  to  the  left  of  the  third  or  second  lumbar  vertebra,  crossing  in  front 


THE  ABDOMINAL  VISCERA  337 

of  the  crura  of  the  diaphragm  and  the  great  vessels.  It  crosses  the  vena 
cava  where  the  left  renal  vein  enters  it.  Though  this  is  considered  the 
normal  arrangement,  exceptions  are  frequent,  and  according  to  Dwight 
the  third  portion  does  not  cross  the  aorta  except  in  20  per  cent,  of  cases. 
It  is  the  most  fixed  part  of  the  duodenum,  and  is  only  covered  in  front  by 
peritoneum,  continuous  with  the  lower  layer  of  the  mesocolon. 

Where  the  superior  mesenteric  vessels,  which  emerge  between  it  and  the 
pancreas,  and  the  root  of  the  mesentery  cross  the  front  of  the  duodenum, 
the  latter  is  free  of  peritoneum.  At  this  point  an  obstruction  of  the 
duodenum  may  occur  from  the  pressure  upon  it  by  the  root  of  the 
mesentery  when  the  latter  is  pulled  upon  by  the  weight  of  the  intes- 
tines hanging  in  the  pelvis,  especially  when  they  are  pushed  down  by 
a  dilated  stomach.  Such  an  "arteriomesenteric  obstruction"  is  a  pri- 
mary or  contributing  cause  of  acute  dilatation  of  the  stomach  in  over 
27  per  cent,  of  the  cases.  In  such  cases  relief  follows  lying  on  the 
belly  or  in  the  knee-chest  position  (Conner).  I  have  verified  this  in 
a  recent  case. 

The  fourth,  or  ascending  part,  about  2.5  cm.  (1  in.)  long,  ascends  in 
front  of  the  left  crus  of  the  diaphragm  to  the  second  or  first  lumbar 
vertebra,  so  that  the  end  and  the  beginning  of  the  duodenum  are  nearly 
at  the  same  level,  and  both  are  held  firmly  suspended.  According  to 
Dwight  it  is  in  front  of  or  just  crosses  to  the  left  of  the  aorta  in  most 
cases,  and  may  be  wholly  on  the  right  side  (in  1  case  in  9).  It  ends  by 
turning  forward  into  the  jejunum  at  the  duodenojejunal  angle.  This 
part  is  firmly  held  in  place  by  a  band  of  fibrous  tissue,  containing  some 
muscle  fibers,  that  descends  from  the  left  crus  of  the  diaphragm  and  is 
continued  into  the  mesentery  between  its  folds,  the  suspensory  muscle 
of  the  duodenum  and  mesentery  (Ivockwood).  (See  Mesentery.)  In  con- 
sequence of  the  latter,  the  duodenojejunal  bend  remains  unaltered  in 
position,  no  matter  how  much  the  stomach  and  intestines  are  displaced. 
Peritoneum  covers  the  fourth  portion  in  front  and  partly  at  the  sides. 

In  about  50  to  75  per  cent,  of  the  cases  examined,  a  fold  of  peritoneum 
is  to  be  found  passing  from  the  anterior  surface  of  this  portion  of  the 
duodenum  to  the  parietal  peritoneum  on  its  left  side.  This  fold  is  the 
anterior  boundary  of  a  triangular  'pouch  which  lies  to  the  left  of  the  gut, 
;iml  is  known  ;is  the  inferior  fossa  duodenojejunalis,  or  Treitz'  fossa.  Its 
apex  is  below  the  bend  between  the  third  and  fourth  portions,  the  opening 
lies  superiorly  and  admits  the  tip  of  the  finger  and  sometimes  of  the 
thumb.  The  fold  is  the  remains  of  the  Petal  "duodenal  fold."  The 
duodenojejunal  junction  actually  occupies  the  fossa.  The  fossa  is 
exposed  by  retracting  the  transverse  colon  upward  and  <he  upper  end  of 
the  jejunum  to  the  right.  It  is  important  as  being  the  starting  point  of  a 
retroperitoneal  hernia.  This  is  small  at  first,  but,  gradually  dilating  the 
a,  the  latter  may  eventually  contain  nearly  the  entire  small  intestine, 
b   in  the  ca  <•  reported  by  Sir  Astley  ( Jooper  and  in  several  others  observed 

ince.      Three  or  four  other  foss;i-  are  described  ;if   the  duodenojejunal 

junction. 
All  parts  of  the  duodenum  have  been  rv/ptv/rejl  by  violence,  (hough 
22 


338  THE  ABDOMEN 

this  is  not  common.  The  duodenum  may  be  wounded  from  behind  with- 
out opening  the  peritoneum,  owing  to  its  large  non-peritoneal  surface. 
Only  the  first  portion  has  ever  been  found  in  a  hernia.  It  will  be  noticed 
that  the  shape  of  the  duodenum  is  not  unlike  that  of  a  trap  used  in 
plumbing,  and  it  is  not  unlikely  that  it  acts  as  such,  preventing  the 
regurgitation  of  intestinal  gas  into  the  stomach. 

The  Jejunum. — The  jejunum  (jejunus,  empty,  i.  e.,  the  condition  in 
which  it  is  usually  found  after  death)  and  the  ileum  (eUecv — to  twist,  i.  e., 
the  curved  or  twisted  intestine)  lie  for  the  most  part  inside  of  the  more 
fixed  large  intestine.  Their  attachment  to  the  posterior  abdominal  wall  by 
the  mesentery  allows  of  such  free  motion  of  the  coils  on  one  another  that 
they  are  well  adapted  to  withstand  the  effects  of  pressure  and  contusion, 
an  important  fact,  for  of  all  viscera  they  are  most  exposed  to  injury. 

In  consequence  of  their  freedom  of  motion,  a  definite  and  constant 
position  of  the  different  coils  is  not  possible.  Yet  in  general  they  are 
disposed  in  an  irregularly  curved  manner  from  left  to  right,  and  the 
jejunum  is  largely  above  the  ileum  and  occupies  the  umbilical  and  left 
lumbar  and  iliac  regions,  while  the  ileum  is  found  in  the  pelvis,  the 
hypogastrium,  and  the  right  side.  They  lie  mostly  within  the  frame 
formed  by  the  ascending,  transverse,  and  descending  colon,  i.  e.,  mostly 
in  the  umbilical  and  hypogastric  regions,  but  they  overlap  the  colon  in 
the  lumbar  and  iliac  regions  unless  it  is  distended.  For  directions  for 
following  the  jejunum  and  ileum  to  either  end  see  Mesentery  (p.  323). 
To  find  the  commencement  of  the  jejunum  (as  for  gastroenterostomy) 
the  omentum  and  transverse  colon  should  be  lifted  up  and  the  small 
intestine  pressed  to  the  right.  Then  following  the  mesocolon  back  to  its 
attachment  in  the  median  line,  the  jejunum  is  felt  or  seen,  usually  just  to 
the  left  of  the  median  line.  In  the  reclining  position  the  first  loop  of 
jejunum  naturally  sinks  toward  the  left,  as  far  as  its  mesentery  allows, 
but  in  the  upright  and  other  positions  this  portion  probably  has  no  fixed 
direction. 

Some  coils  of  the  jejunum,  corresponding  to  the  longest  part  of  the 
mesentery,  are  found  in  the  pelvis.  The  terminal  coils  of  the  ileum  just 
proximal  to  the  ileocecal  valve  are  also,  as  a  rule,  found  in  the  pelvis. 
The  fetal  pelvis  contains  no  small  intestine,  and  the  amount  present  in 
the  adult  pelvis  depends  upon  the  distention  of  the  bladder,  rectum,  and 
sigmoid  flexure,  and  the  size  of  the  female  pelvic  organs.  The  coils  of 
the  ileum  and  jejunum  occupying  the  pelvis  are  of  interest,  as  they  are  apt 
to  become  involved  and  adherent  in  pelvic  peritonitis,  and  the  ileum,  or 
lowest  part,  is  that  most  frequently  found  in  inguinal  or  femoral  hernia, 
though  the  jejunum,  from  its  position  in  the  left  iliac  fossa,  would  also 
be  likely  to  be  present  in  left  inguinal  or  femoral  hernia.  Hence,  theoreti- 
cally, the  symptoms  of  obstruction  would  be  likely  to  be  more  acute  in  a 
strangulated  hernia  on  the  left  side  than  in  one  on  the  right  side,  because 
the  jejunum  is  more  likely  to  be  present  in  the  former.  In  this  connection 
we  may  say  that  intestinal  obstruction,  or  other  lesions  of  the  intestine,  are 
more  serious  the  nearer  they  are  to  the  stomach,  and  hence  are  more 
serious  in  the  jejunum  than  in  the  ileum.    In  obstruction  of  the  jejunum 


THE  ABDOMINAL  VISCERA  339 

nutrition  is  much  interfered  with,  for  vomiting  commences  early  and  is 
very  frequent,  the  abdomen  is  but  little  distended,  the  expression  becomes 
quickly  pinched  and  anxious,  and  the  progress  of  the  case  is  rapid  and 
acute,  while  similar  lesions  of  the  ileum  are  less  acute.  The  acuteness  of 
the  symptoms  and  the  fatality  of  strangulated  umbilical  hernia  may 
depend  partly  upon  its  liability  to  contain  coils  of  the  upper  jejunum. 

The  ileum,  from  its  position,  is  more  apt  to  be  strangulated  by  internal 
bands,  holes  in  the  mesentery,  etc.  The  coils  of  intestine  must  accommo- 
date themselves  each  moment  to  changes  in  form  and  position  of  the 
peritoneal  cavity,  depending  upon  the  movements  of  the  diaphragm  and 
abdominal  muscles,  the  filling  or  emptying  of  the  viscera,  the  presence 
of  effusions,  tumors,  etc.  Hence  the  rigid  fixity  of  the  abdominal 
muscles  and  the  absence  of  diaphragmatic  breathing  in  peritonitis,  to 
diminish  the  movements  of  the  inflamed  peritoneal  surfaces.  A  similar 
object  is  sought  in  the  opium  or  the  starvation  treatment  of  peritonitis 
by  decreasing  the  peristaltic  movements  of  the  coils  against  one  another. 
Abdominal  tumors  cause  a  displacement  or  change  of  position  of  the 
intestines,  which  varies  with  the  size  and  position  of  the  tumor,  and  is 
useful  in  the  diagnosis  of  the  latter.  In  like  manner  the  small  intestine 
floats  on  the  fluid  in  cases  of  ascites  so  as  to  be  mostly  in  front  or  above, 
according  as  the  patient  is  reclining  or  erect.  The  upper  part  of  the 
jejunum  and  the  lower  part  of  the  ileum  are  the  most  fixed  portions,  as 
their  mesentery  is  shorter  than  elsewhere,  and  hence  they  are  most  liable 
to  rupture  from  injury.  But  the  jejunum,  40  to  50  cm.  (16  to  20  in.)  from 
its  upper  end,  is  freely  enough  movable  to  allow  it  to  be  drawn  up  without 
tin-ion  over  the  transverse  colon  and  fastened  to  the  stomach  in  anterior 
gastro-enterostomy. 

Though  the  upper  two-fifths  of  the  small  intestine  below  the  duod- 
enum is  called  the  jejunum,  and  the  lower  three-fifths  the  ileum,  there 
is  no  definite  point  where  one  may  be  said  to  end  and  the  other  to  begin. 
It  i>  often  difficult  to  tell  to  which  part  a  given  coil  belongs  when  it  is 
exposed  by  operation  or  accident,  especially  if  the  size  or  appearance  is 
altered  by  disease.  Bui  between  the  upper  end  of  the  jejunum  and  the 
lower  end  of  the  ileum  (here  is  considerable  difference.  The  diameter 
of  the  former  is  3  to  3.5  cm.  0  {  to  \\  in.);  of  the  latter,  2.5  to  3  cm.  (1  to 

1 }  in.).  The  walls  of  the  former  ;ire  more  vascular  and  thick*  r,  owing 
largely  to  the  valvules  connivenfes,  which  arc  large  and  numerous,  while 
they  arc  scanty  in  the  lower  pari  of  the  jejunum  and  nearly  wanting  in 
the  upper  pari  of  the  ileum.  If  the  intestine  is  opened  and  presents  a 
number  of  well-developed  valvulss  conniverites,  we  may  infer  that 

tin-  opening  is  in  the  upper  jejunum,  and  if  few  or  no  valvuhe  con- 
QiventeS,  that  il  i-  in  the  lower  ileum.  These  valvuhr  arc  readily  felt 
on  palpation  in  the  upper  part  ('jejunum),  not  in  the  lower  intestine 
(ileum).  If  we  look  through  the  empty  gui  toward  a  light,  the  lines  of 
the  \  :i  1  \  1 1  l;i  ■  eonnivciitcs  can  be  well  seen. 

Monks  has  described  a   method  of  identifying  the  position  of  a,  given 

loop  of  small  intestines  by  the  arrangement  of  the  vessels  in  the  mesen- 
tery.   The  branches  of  the  superior  mesenteric  artery  in  the  mesentery 


340  THE  ABDOMEN 

unite  with  one  another  to  form  a  series  of  loops  from  which  the  straight 
vasa  recta  run  to  the  bowel.  This  holds  for  the  first  90  cm.  (3  ft.). 
Then  a  series  of  secondary  and  even  tertiary  loops  appear  as  we  proceed 
down  the  intestine,  the  loops  getting  nearer  and  nearer  the  gut,  and  the 
vasa  recta  becoming  shorter,  i.  e.,  3  to  5  cm.  above,  1  cm.  or  less  below. 
In  the  lower  ileum  the  loops  lose  their  characteristic  appearance  and  the 
vasa  recta  become  branched.  The  contents  also  vary  in  the  two  parts 
of  the  bowel  considered,  corresponding  to  the  stage  of  digestion. 

In  the  persistent  vomiting  of  intestinal  obstruction  or  peritonitis, 
after  the  stomach  is  emptied,  the  bowel  contents  are  regurgitated  by 
reverse  peristalsis  and  are  vomited.  The  character  of  the  vomit  changes 
from  the  sour  stomach  contents  to  the  bitter  bile-laden  contents  of  the 
upper  bowel,  and  finally  the  matter  may  become  fecal.  Fecal  or  ster- 
coraceous  vomiting  means  vomiting  of  intestinal  contents,  though  the 
latter  do  not  really  become  fecal  in  odor  or  character  above  the  lower 
ileum.  The  stomach  and  upper  bowel  may  be  nearly  or  quite  free  of 
bacteria.    The  latter  increase  in  number  as  we  proceed  down  the  intestine. 

The  Layers  of  the  Intestinal  Wall. — The  peritoneal  coat  is  so  nearly 
complete  that  a  wound  from  without  or  a  perforation  from  within  can 
scarcely  occur  without  involving  it.  Between  the  two  layers  of  the  mesen- 
tery where  they  pass  onto  the  bowel  there  is  a  strip  of  the  latter  averaging 
8  mm.  (T5g-  in.)  in  width  uncovered  by  peritoneum.  This  area  is  the  usual 
cause  of  the  occasional  leakage  after  enterorrhaphy,  for  the  essential 
feature  of  the  operation  is  that  the  serous  coat  of  both  ends  of  the  divided 
gut  should  be  brought  together  at  all  points.  In  enterorrhaphy  or  in  the 
use  of  the  Murphy  button,  or  other  aids  to  intestinal  anastomosis,  the  two 
layers  of  the  mesentery,  where  they  pass  onto  the  bowel,  should  be  care- 
fully brought  closely  together  by  suture  so  as  to  complete  the  circle  of  the 
serous  coat.  Loss  of  substance  of  a  limited  area  of  the  peritoneal  coat  may 
occur  without  serious  impairment  of  the  strength  or  function  of  the  part 
of  the  bowel  involved,  though  strong  adhesions  are  likely  to  occur  here. 

The  inner  or  circular  muscular  coat  is  three  times  as  thick  as  the  outer 
layer  of  longitudinal  fibers,  hence  a  longitudinal  wound  gapes  more  than 
a  transverse  one.  Owing  to  the  greater  thickness  of  the  longitudinal 
fibers  along  the  free  border  of  the  gut,  transverse  wounds  across  this 
part  of  the  gut  gape  more  than  elsewhere.  Wounds  of  the  jejunum 
gape  more  than  those  of  the  ileum,  owing  to  the  greater  muscular 
development  of  the  former.  Minute  wounds  of  the  intestine  are  closed  by 
the  contraction  of  the  muscular  coat  so  as  to  prevent  extravasation.  The 
bowels  have  been  punctured  without  ill  effects  in  many  places  to  allow 
the  escape  of  gas  when  excessive  tympanites  exists,  and  in  abdominal 
operations  to  facilitate  the  return  of  the  intestine  within  the  abdomen. 
At  present,  however,  fewer  and  larger  openings  are  usually  made  and 
afterward  sutured.  Wounds  somewhat  larger  than  punctures  are 
plugged  by  the  protrusion  of  the  loose  mucous  membrane,  which  may  or 
may  not  prevent  extravasation.  Treves1  mentions  a  stab  wound  with  a 
small  puncture  of  the  ileum  which  remained  closed  by  such  a  protrusion 

1  Surgical  Applied  Anatomy. 


PLATE  XXXIII 


FIG.  115 


A  Loop  of  Intestine,  the  Middle  of  which  is  Exactly  Three  Feet 
from  the  End  of  the  Duodenum.  (Monks.) 
The  gut  is  of  large  size.  The  mesenteric  loops  are  primary,  and  the  vasa  recta  large, 
long,  and  regular  in  distribution.  The  translucent  spaces  (lunettes,  between  the  vessels  are 
extensive.  Below,  the  mesentery  is  streaked  with  fat.  The  veins,  which  had  a  distribution 
similar  to  the  arteries,  are  for  simplicity  omitted  from  this  and  from  the  subsequent  drawing 
(The  subject  from  which  the  specimen  was  taken  was  a  male  aged  forty  years,  with  rather 
Usee  than  the  usual  amount  of  fat.    The  entire  length  of  the  intestine  was  twenty-three  feet. 

FIG.   1  16 


A    Loop  of  Intestine  at  Twelve   Feet.     (Monks.) 
'II,  .,.-,,,.-,  ii,  -i-    The  primary   loop    are  lost  in  the  fat,  but  secondary  and  even 

ible     l  he 


recta  are  shorter,  more  irregular,  and  branching. 


THE  ABDOMINAL  VISCERA  341 

of  mucous  membrane,  aided  by  recent  lymph,  for  four  days  when  fatal 
symptoms  suddenly  occurred,  and  it  was  found  postmortem  that  an 
intestinal  worm  (Ascaris  lumbricoides)  had  escaped  through  the  wound 
and  led  the  way  for  extravasation. 

In  larger  wounds  the  size  of  the  opening  is  much  reduced  by  muscular 
contraction.  Thus,  Gross  found  in  longitudinal  wounds  a  reduction  in 
length  of  one-half.  The  mucous  membrane  is  also  much  everted  by 
reason  of  the  muscular  contraction,  and  this  is  to  be  remembered  in 
intestinal  suture,  for  it  must  be  inverted  in  order  to  bring  the  edges  oi 
the  serous  membrane  together,  and  thereby  secure  firm  healing  ot  the 
wound,  for  mucous  membrane  does  not  unite  with  mucous  membrane  on 
its  epithelial  surface. 

In  order  to  secure  the  healing  of  intestinal  wounds  the  serous  layers 
are  somewhat  inverted  by  Lembert,  Halstead,  dishing,  or  similar  sutures. 
The  suture  catches  up  the  serous,  muscular,  and  submucous  layers 
external  to  the  line  of  the  wound,  so  that  the  suture  punctures  do  not 
reach  the  latter,  but  leave  a  narrow  free  strip  on  either  side  ot  it.  Inus 
when  the  sutures  are  tightened  the  edges  are  inverted  and  the  strips  ot 
the  peritoneal  coat  between  them  and  the  lines  of  suture  on  each  side  are 
brought  in  contact.  . 

The  worm-like  peristaltic  movements  of  the  intestine  are  the  result  ot 
the  consecutive  contraction  of  successive  portions  of  the  muscular  coat. 
This  may  be  seen  through  thin  abdominal  walls  and  heard  on  auscultation 
where  the  latter  are  thicker.  It  is  increased  when  there  is  a  mechani- 
cal obstruction,  and  diminished  or  wanting  when  there  is  paralytic 
(dynamic)  obstruction.  Abnormally  this  action  may  be  reversed,  as  in 
intestinal  obstruction,  and  force  the  contents  toward  the  stomach  instead 
of  toward  the  colon,  and  thus  produce  fecal  vomiting.  "Colic  is  due  to 
an  irregular  or  spasmodic  contraction  of  the  muscular  wall,  and  is  anal- 
ogous to  a  cramp  in  the  leg,  etc.  It  is  not  associated  with  abdominal 
tenderness  or  rigidity.  . 

The  caliber  of  the  intestine  varies  with  the  contraction  ot  its  muscular 
wall     When  empty  the  bowel  becomes  contracted.    It  may  be  distended 
by  accumulated  fecal  matter  or  by  gas,  so  as  to  be  larger  than  the  large 
intestine.     In  septic  peritonitis  and  in  some  other  septic  conditions  the 
muscular  wall  in  time  becomes  paralyzed  by  septic  poisoning.     Peri- 
stalsis  therefore,  ceases  and  obstruction  follows,  while  the  stagnant  teca 
matter  develops  gas  which  distends  the  bowel.     From  the  peritoneal 
coal  of  jheepcomes  the  "catgut"  of  commerce,  so  much  used  in  surgery 
The  mucous  membrane  is  loosely  connected  with  the  layers  on  which  it 
o  as  to  permit  it  to  move  freely  over  them.   This  allows  it  to  become 
everted,  so  as  to  plug  a  small  wound,  and  to  become  prolapsed  m  some 
i    of  artificial  anus,  thus  preventing  spontaneous  closure. 
/',,/,/>  patches,  occurring  principally  in  the  ileum  and  especial ly  in 
its  lower  two-thirds,  an-  placed  lengthwise  of  the  intestine  on  the  side 
opposite  the  mesenteric  attachment,  and  hence  are  best  exposed  by 

opening  Hie  gUl  along  (lie  attachment  of  the  mesentery.     They  are  lie 

eat  of  typhoid  as  well  as  tuberculous  ulcers,  the  former  of  which  usually 


342  THE  ABDOMEN 

extend  longitudinally  in  the  axis  of  the  patch,  the  latter .  transversely 
in  the  direction  of  the  encircling  bloodvessels.  In  one  case  of  perforating 
typhoid  ulcer,  on  which  the  writer  operated,  the  long  axis  of  the  ulcer 
was  transverse.  In  the  great  majority  of  cases  a  typhoid  perforation 
occurs  in  the  lower  two  feet  of  the  ileum. 

The  vessels  of  the  small  intestines  enter  or  emerge  from  the  bowel  along 
the  narrow  strip,  uncovered  by  peritoneum,  at  the  mesenteric  attachment. 
The  arteries  run  transversely  from  either  side,  thus  encircling  the  gut. 
This  arrangement  of  the  arteries  sometimes  enables  us  to  distinguish  the 
intestines  from  other  structures  in  case  of  doubt. 

The  large  anastomosing  branches,  which  lie  between  the  two  layers 
of  the  mesentery,  are  liable  to  be  injured  in  stab  or  gunshot  wounds  and 
to  give  rise  to  serious  hemorrhage.  The  vessels  of  the  mesentery  may 
be  occluded  by  thrombosis  or  embolism.  In  spite  of  the  apparently 
free  anastomoses  the  collateral  circulation  is  very  rarely  established. 
Whether  the  artery,  the  vein,  or  both  are  occluded,  gangrene  results  and 
may  involve  2.5  to  5  cm.  (1  to  2  in.)  or  many  feet  of  the  gut. 

The  veins  accompany  the  arteries  singly,  and  flow  through  the  superior 
mesenteric  into  the  portal  vein.  Hence  they  are  affected  by  portal  con- 
gestion in  some  conditions  of  the  liver,  and  septic  infection  may  be  carried 
by  them  to  the  latter  from  the  intestine,  sometimes  producing  pylephle- 
bitis, or  abscess  of  the  liver. 

The  lymphatics  form  two  sets,  as  in  the  stomach,  a  deep  set  in  the 
mucous  membrane,  and  a  superficial  set  in  the  muscular  layer.  In  the 
mesentery  they  are  known  as  chyle  vessels,  on  account  of  the  milky  fluid 
they  contain.  In  emergency  operations,  performed  not  long  after  a 
meal,  these  vessels  show  very  plainly  as  fine  white  streaks.  They  enter 
numerous  (130  to  150,  Quain)  lymph  nodes  between  the  folds  of  the 
mesentery,  at  and  near  its  parietal  attachment,  which  are  subject  to 
enlargement  in  lesions  of  the  intestine  like  tuberculosis,  typhoid  fever, 
dysentery,  cancer,  etc.  In  case  of  enlargement  of  these  nodes  the  lesion 
should  be  sought  in  the  intestine. 

The  nerves  come  from  the  celiac  and  superior  mesenteric  plexuses  of 
the  sympathetic,  with  some  fibers  from  the  right  pneumogastric.  For 
the  connection  between  the  nerves  of  the  intestine  and  those  of  the  abdom- 
inal wall,  see  the  latter  (p.  281). 

Meckel's  diverticulum,  a  persistent  proximal  portion  of  the  vitelline  duct, 
is  a  blind  glovefinger-like  pouch  having  the  same  layers  as  the  ileum  and 
a  lumen  continuous  with  it.  It  arises  from  the  free  margin  of  the  ileum, 
from  30  to  90  cm.  (1  to  3  ft.)  from  its  lower  end.  It  averages  5  to  7.5  cm. 
(2  to  3  in.)  in  length,  but  may  be  much  larger,  and  ends  in  a  free  cylindri- 
cal, conical,  or  globular  extremity,  or  in  a  fibrous  band  which  may  connect 
it  with  the  umbilicus,  as  in  fetal  life,  or  with  other  parts.  It  can  cause 
obstruction,  when  its  end  is  adherent,  by  forming  a  bridge  beneath  which 
a  loop  of  bowel  may  be  strangulated,  or  by  pulling  on  the  ileum  at  its 
attachment  so  as  to  kink  the  latter.  It  occurs  once  in  about  50  cases,  has 
been  found  in  external  hernia?,  and  may  give  rise  to  a  condition  resembling 
appendicitis. 


THE  ABDOMINAL  VISCERA  343 

In  operations  upon  the  intestines,  or  in  penetrating  abdominal  wounds 
which  may  involve  them,  it  is  to  be  remembered  that  they  are  separated 
in  great  part  from  the  anterior  abdominal  wall  by  the  great  omentum. 
As  the  omentum  is  the  only  thing  that  intervenes  between  the  intestines 
and  the  abdominal  wall,  the  intestines  are  much  exposed  to  contusions 
by  blows,  the  effects  of  which  are  intensified  if  received  unawares,  when 
the  belly  wall  is  relaxed,  or  if  the  body  cannot  bend  or  yield  to  the  blow. 
In  this  way  the  intestine  may  be  torn,  severed,  or  so  bruised  as  to  slough 
subsequently  and  thus  lead  to  a  perforative  peritonitis.  This  possibility 
should  be  borne  in  mind  in  cases  of  severe  abdominal  contusions  and  the 
prognosis  be  reserved. 

In  bullet  or  stab  wounds,  penetrating  and  traversing  the  abdomen,  the 
intestines  almost  always  receive  multiple  injuries,  the  number  of  which 
varies  but  is  generally  greater  in  those  wounds  whose  course  is  transverse 
or  oblique,  because  more  coils  of  intestine  are  thus  met  with.  Occa- 
sionally a  bullet  or  knife  may  pass  among  the  intestines  without  wounding 
them.  Several  such  cases  are  reported  where  the  fact  has  been  demon- 
strated by  operation,  but  it  occurs  in  less  than  2  or  3  per  cent,  of  cases. 
A  bullet  whose  course  passes  through  near  the  edge  of  a  piece  of  intestine 
makes  a  larger  opening  than  one  passing  through  the  centre,  and  the 
wound  of  entrance  and  exit  may  be  continuous  if  they  lie  along  the  edge 
of  the  gut. 

The  end  of  the  ileum  may  slip  through  the  ileocecal  valve  and  become 
prolapsed  into  the  colon,  possibly  even  to  the  anus.  This  is  one  variety 
of  intussusception,  and  occurs  mostly  among  children  (p.  347). 

Operations. — Laparotomy  or  celiotomy  applies  simply  to  the  procedure 
of  opening  the  abdominal  cavity  for  any  purpose,  and  is  referred  to 
under  the  Abdominal  Wall.  The  bowel  may  be  opened  (enterotomy)  to 
remove  an  impacted  foreign  body,  in  which  case  it  is  sutured  immedi- 
ately; or  to  make  an  artificial  anus  above  an  obstruction,  after  the  intes- 
tine Lb  sutured  into  the  wound,  in  which  case  a  low  point  in  the  ileum 
(ileostomy)  should  be  selected  if  possible.  The  permanent  opening  of 
the  bowel  below  an  obstruction  and  its  suture  into  the  wound  for  the 
purpose  of  feeding  the  patient  (enterostomy)  is  usually  done  in  the  upper 
jejunum  (jejunostomy),  so  that  the  food  may  pass  through  the  greatest 
possible  length  of  intestine,  but  the  operation  is  not  very  popular.  In 
enterectomy  a  portion  of  the  bowel  is  cut  out  or  resected  for  gangrene, 
tumors,  stricture,  multiple  injuries  from  bullet  or  stab  wounds,  and  many 
other  causes.  In  a  successful  case  of  closure  of  sixteen  bullet  wounds  of 
the  small  intestine,  reported  by  tlie  writer,  7.5  or  10  cm.  (3  or  4  in.)  of 
the  gut  was  resected,  as  there  were  four  holes  within  5  em.  (2  in.),  the 
closure  of  which  would  have  caused  a  stricture  or  kinking  of  the  bowel. 
The  successful  resection  of  330  cm.  (11  ft.)  (Ruggi)  of  the  intestine  has 

been  reported,  and  manj  cases  where  more  than  one  meter  has  been 
-  tecL 
After  resection  intestinal  suture  is  performed,  preferably  by  the  end- 
to-end  suture,  or,  if  it  is  not  possible  to  bring  the  ends  together  without 
tension,  lateral  anastomosis  may  be  made  after  inverting  and  closing  the 


344  THE  ABDOMM 

divided  ends.  As  a  palliative  operation  lateral  anastomosis  is  often  made 
between  the  coils  above  and  below  a  lesion  without  resection  of  the 
diseased  parts  (intestinal  exclusion).  The  end-to-end  suture  is  preferable 
if  feasible,  for  peristalsis  will  follow  its  natural  course  and  there  is  little 
or  no  danger  of  stricture  from  contraction  of  the  opening.  Various 
mechanical  aids  to  facilitate  both  forms  of  intestinal  union  and  to  save 
time  have  been  devised,  among  the  most  perfect  of  which  is  the  Murphy 
button.  The  importance  of  securing  perfect  apposition  of  the  opposing 
peritoneal  surfaces  throughout,  in  the  suture  of  intestinal  wounds  or 
operations,  has  been  referred  to  above. 

The  Large  Intestine. — Ileocecal  Region. — The  cecum  (Fig.  118),  or 
blind  head  of  the  colon,  is  the  large  cul-de-sac  of  the  colon  that  lies  below 
the  entrance  of  the  ileum.  In  man  and  the  carnivora  it  is  rudimentary, 
while  in  the  herbivora  and  graminivora  it  is  of  great  size,  so  that  in  man 
it  has  been  called  an  anatomical  protest  against  vegetarianism.  Its 
width,  7.5  cm.  (3  in.),  is  greater  than  its  length,  6.5  cm.  (2^  in.)  and  it  is 
relatively  and  absolutely  larger  in  the  adult. 

Fig.  117 


Type  1  Type  2  Type  3  Type  4 

Schematic  table  of  types  1,  2,  3,  and  4  of  human  ceca. 

As  to  shape,  four  types  may  be  distinguished,  as  seen  in  Fig.  117. 
(1)  The  conical  fetal  or  infantile  type  persists  in  about  2  per  cent,  of  cases 
among  adults.    Type  2  occurs  in  the  adult  in  3  per  cent,  of  cases.    Type 

3  is  the  common  or  normal  form,  occurring  in  man  in  90  per  cent,  of  cases. 
In  it  the  right  sacculus  and  the  anterior  wall  have  outgrown  the  left  side, 
so  that  they  form  the  lower  end  of  the  cecum,  while  the  root  of  the  appen- 
dix, to  which  converge  the  longitudinal  bands,  has  been  displaced  upward, 
inward,  and  backward,  to  about  16  mm.  (f  in.)  below  the  entrance  of  the 
ileum.  The  longitudinal  bands  are  seen  to  be  a  uniform  and  useful  guide 
to  the  base  of  the  appendix.  The  anterior  band  is  our  best  guide  to  the 
root  of  the  appendix,  for  it  is  the  most  accessible.    Type  4,  comprising 

4  or  5  per  cent,  of  cases,  is  an  exaggeration  of  3,  in  which  the  root  of 
the  appendix  is  displaced  to  the  inferior  ileocecal  angle  by  the  atrophy 
of  the  left  sacculus. 

The  cecum  is  the  most  superficial  portion  of  the  large  intestine,  and 
hence  is  most  exposed  to  injury.  For  the  same  reason  and  its  mobility 
it  is  selected  for  colostomy  on  the  right  side.  When  full  it  occupies  most 
of  the  iliac  fossa,  and  is  in  contact  with  the  anterior  abdominal  wall,  but 
when  empty,  as  after  fasting  or  when  there  is  obstruction  in  the  small 


THE  ABDOMINAL  VISCERA 


345 


intestine,  it  is  smaller  and  covered  by  coils  of  the  small  intestine.  Its 
normal  position  is  in  the  right  iliac  fossa,  on  the  psoas  muscle,  above  the 
outer  half  of  Poupart's  ligament,  with  its  apex  projecting  over  the  inner 
edge  of  that  muscle  and  lying  a  little  to  the  inside  of  the  vertical  plane 
drawn  through  the  middle  of  Poupart's  ligament.  It  may  sometimes  lie 
farther  mesially,  extending  down  into  the  pelvis  or  toward  or  even  across 
the  median  line.  Not  infrequently  it  lies  more  to  the  right,  entirely  on  the 
iliacus  muscle  or  with  only  its  apex  on  the  psoas.  It  is  not  infrequently 
displaced  downward  so  as  to  be  found  in  a  right  inguinal  or  occasionally 
in  a  femoral  hernia,  and  it  has  even  been  found  in  left-sided  hernias. 
Such  hernia?  are  provided  with  a  complete  peritoneal  sac  except  in  very 
rare  cases  (see  also  pp.  294  and  346). 

The  fetal  cecum  is  situated  at  first  within  the  umbilical  region,  thence 
it  ascends  into  the  left  hypochondrium,  from  which  it  passes  across  into 
the  right  hypochondrium  and  then  descends  into  the  right  iliac  fossa. 


Fig.  118 


ILEO-COLIC 
FOSSA 


COURSE  OF  APPENDIC.A. 
BEHIND  ILEUM 


MESCNTERIOLUM 
APPENDIC.A. 


Cecum,  appendix,  and  end  of  ileum,  with  the  blood  supply  and  the  neighboring  fossa. 
Somewhat  schematic.      (Merkel.) 


An  interesting  and  important  variation  in  the  position  is  that  in  which  it 
remains  undescended  from  its  fetal  position  above  and  to  the  left  of  the 
Umbilicus,  or  lower  down  near  the  pelvic  brim,  the  ascending  and  trans- 
colon  being  absent.  More  often  it  is  partly  descended  and  just 
below  the  liver  or  at  any  point  between  the  liver  and  its  normal  position. 
Accordingly  it  may  even  be  found  in  a  congenital  umbilical  hernia.  It 
18  not  uncommon  to  find  the  cecum  unusually  high  on  the  right  side, 
having  been  arrested  in  its  descent  into  the  right  iliac  fossa.  The  writer 
has  met  with  such  cases  in  operating  for  appendicitis  where  the  cecum 
above  the  cresl  of  die  ileum.  The  importance  of  these  irregular 
po  ition  -  of  the  cecum  1  i«-.s  in  the  fact  thai  the  appendix  is  correspondingly 

Bhifted  in  position. 

The  direction  of  the  cecum  is  not  quite  vertical,  but   inclines  slightly 
inward  below.     If  we  take  as  itS  Upper  limit  the  lower  edge  of  the  ileocolic; 


346  THE  ABDOMEN 

junction,  the  cecum  is  completely  covered  by  peritoneum.  The  latter, 
therefore,  is  first  reflected  onto  the  iliac  fossa  from  the  ascending  colon, 
so  that  the  subperitoneal  areolar  tissue  of  the  iliac  fossa  is  never  in  direct 
contact  with  the  posterior  surface  of  the  cecum,  which  is  free  in  the 
peritoneal  cavity.  The  level  of  this  reflection  of  peritoneum  and  of  the 
upper  end  of  the  cecum  varies,  but  is  usually  about  midway  between  the 
level  of  the  anterior  superior  spine  and  of  the  highest  point  of  the  iliac 
crest.  Quain,  Berry,  and  others  state  that  in  5  per  cent,  of  cases  the 
peritoneum  is  reflected  just  below  the  upper  end  of  the  cecum,  leaving 
the  posterior  wall  of  that  part  connected  with  the  subperitoneal  areolar 
tissue,  but  they  make  the  cecum  reach  a  higher  level,  i.  e.,  that  of  the 
ileocecal  valve.  The  mobility  of  the  cecum  depends  largely  upon  the  dis- 
tance between  its  tip  and  the  reflection  of  peritoneum  posteriorly  from 
the  colon,  and  especially  upon  the  presence  of  an  ascending  mesocolon. 
A  mobile  cecum  may  even  find  its  way  into  a  left  inguinal  or  femoral 
hernia.  In  some  cecal  hernise  the  peritoneum  of  the  iliac  fossa  and  its 
reflection  onto  the  lower  end  of  the  colon  appears  to  have  slid  down  so 
as  to  form  part  of  the  posterior  wall  of  the  sac. 

Foreign  bodies  that  have  been  swallowed  and  have  passed  the  pylorus 
are  apt  to  lodge  in  the  cecum,  partly  from  the  effects  of  gravity.  They 
may  ulcerate  through  the  cecal  wall  and  cause  perityphilitis.  The  largest 
accumulation  of  feces  in  cases  of  fecal  impaction  is  often  found  in  the 
cecum.  Hence  stercoral  ulcers,  due  to  the  pressure  irritation  of  retained 
or  impacted  fecal  masses,  are  more  common  in  the  cecum  than  in  any 
other  part  of  the  intestine.  The  cecum,  according  to  Cobbold,  is  the  seat 
of  the  pin-worm  (Oxyuris  vermicularis),  but  others  claim  that  this  is  lower 
down  in  the  colon.  Intestinal  concretions  are  not  uncommonly  met  with 
here,  but  normally  the  contents  of  the  cecum  are  fluid.  Tuberculous 
inflammation  with  great  hyperplasia  and  induration  sometimes  involves 
the  ileocecal  region,  producing  a  large  "ileocecal  tumor,"  which  may  cause 
obstruction  of  the  bowels  or  become  perforated  and  set  up  peritonitis. 

In  cases  of  intestinal  obstruction  the  condition  of  the  cecum  may 
assist  in  diagnosis.  If  the  obstruction  be  in  the  colon  the  cecum  will  be 
found  greatly  distended,  while  it  is  normal  or  collapsed  in  cases  of 
obstruction  of  the  small  intestine.  The  cecum  is  capable  of  enormous 
distention,  if  gradually  effected,  and  has  been  observed  larger  than  the 
full  stomach.  Flexing  the  thigh  upon  the  abdomen  will  empty  a  slightly 
distended  cecum,  if  normal  in  position.  The  structure  of  the  cecum  is 
like  that  of  the  colon,  the  peculiarities  of  which  are  described  later. 

The  ileocecal  or  ileocolic  valve  guards  the  entrance  of  the  ileum  into  the 
large  intestine  at  the  junction  of  the  cecum  and  colon.  It  is  normally  found 
on  the  internal  and  posterior  aspect  of  the  large  intestine,  but  rarely, 
by  a  rotation  of  the  latter,  the  ileum  may  pass  behind  it  and  open  on  its 
outer  side,  or  it  may  open  more  in  front  when,  occasionally,  the  posterior 
part  of  the  cecum  is  more  developed  than  the  anterior.  The  valve  con- 
sists of  two  flaps  formed  by  the  invagination  of  the  ileum  into  the  colon. 
It  is  generally  found  5  cm.  (2  in.)  internal  to  the  anterior  superior  iliac 
spine^and  about  in  the  spino-umbilical  line,  but  it  is  subject  to  frequent 


THE  ABDOMINAL  VISCERA  347 

variations  in  position.  It  is  composed  of  the  mucosa,  submucosa,  and 
circular  fibers,  while  the  peritoneum  and  longitudinal  fibers  pass  directly 
over  the  angle  between  the  ileum  and  the  large  intestine  and  form  no 
part  of  the  valve.  Hence  if  the  two  outer  layers  are  divided  and  traction 
is  made  on  the  ileum  the  valve  is  unfolded  and  pulled  up  into  the  ileum, 
which  then  presents  a  funnel-shaped  opening  into  the  large  bowel.  The 
two  flaps  project  nearly  transversely  into  the  lumen  of  the  large  intestine, 
and  this  projection  is  continued  from  either  end  of  the  slit-like  opening 
for  a  short  distance  around  the  circumference  of  the  colon  as  the  frena, 
or  retinacula,  of  the  valve,  similar  to  a  plica  of  the  colon,  so  that  the 
valve  may  be  said  to  open  on  the  summit  of  a  plica. 

When  the  cecum  and  colon  are  distended  the  flaps  of  the  valve  are 
pressed  together,  preventing  regurgitation  into  the  ileum.  In  an  ordinary 
high  enema  the  valve  renders  impossible  the  passage  of  the  fluid  into  the 
ileum,  but  if  a  high  pressure  is  steadily  continued  the  fluid  may  pass  the 
valve,  though  probably  not  before  peritoneal  lacerations  and  other 
damage  to  the  large  intestine  have  occurred.  Hence,  practically,  for 
diagnostic  and  therapeutic  purposes,  the  valve  is  not  permeable  to  fluids 
from  below,  and  the  attempt  to  force  fluids  past  the  ileocecal  valve  from 
below  is  unsafe  and  unjustifiable,  unless  possibly  the  injection  is  given 
very  gradual.  Some  say  that  high  enemata  may  pass  the  valve  in  a 
considerable  proportion  of  cases,  but  in  these  cases  the  valve  is  regarded 
as  imperfect  and  incompetent  from  the  first.  With  air  or  gases  it  is  other- 
wise. Thus,  Senn  has  shown  that  hydrogen  gas  inflated  into  the  colon 
through  the  rectum,  under  a  pressure  of  from  1^  to  2\  pounds,  may  safely 
pass  the  valve,  enter  the  small  intestine,  and  disclose  a  wound  of  the 
latter,  in  case  of  stab  or  bullet  wounds  of  the  abdomen,  or  be  used  in 
the  treatment  of  intussusception.  In  such  cases  the  incompetency  of 
the  valve  depends  upon  gradual  lateral  and  longitudinal  distention  of  the 
cecum,  which  mechanically  separates  the  margins  of  the  valve.  The 
same  explanation  applies  to  those  cases  of  intestinal  obstruction  where 
there  is  evidence  of  the  return  of  the  contents  of  the  large  into  the  small 
intestine,  though  some  deny  that  it  occurs.  The  baneful  effect  of  forced 
high  injections  of  fluids  as  compared  with  that  of  gases  probably  depends 
upon  their  weight  and  lack  of  elasticity.  An  ordinary  high  enema  causes 
the  emptying  of  the  lower  ileum  by  stimulating  its  peristalsis  so  that  there 
is  no  need  to  try  to  force  an  enema  beyond  the  valve.  Narrowing  of  the 
valve,  either  organic  or  spasmodic,  has  been  suggested  as  a  possible  cause 
of  chronic  constipation. 

Intussusception,  the  invagination  or  telescoping  of  one  part  of  the  bowel 
into  the  pari  next  below  it,  generally  OCCUrs  in  this  region,  and  is  most 
common  in  childhood  under  the  age  of  ten  years.  The  ileocecal  form  is 
the  commonest,  and  in  it  the  ileum  with  tin-  cecum  is  prolapsed  down  the 

Colon.     The  ilfiocrail  nil rr  forms  the  njir.r  of  the  iiilussusceptuin,  or  pro- 

lap  ed  mass,  and  may  even  reach  the  rectum  and  present  at  the  anus. 
Electa!  examination  should,  therefore,  always  be  made  in  cases  where 

intussusception  ifl  BUSpected.  In  a  rarer  form,  the  ileocolic,  the  ileum  is 
prolapsed  through  the  Ileocecal   valve  into  and  along  tin;  colon.     The 


348  THE  ABDOMEN 

valve  and  cecum  retain  their  positions  while  the  ileum  forms  the  summit 
of  the  intussusceptum.  A  still  rarer  form  is  the  colic,  where  one  part  of  the 
colon  is  invaginated  into  a  part  below,  but  the  extent  of  this  is  limited  by 
the  shortness  of  the  mesentery  of  the  colon.  In  the  enteric  form  the  small 
intestine  is  invaginated  into  itself.  The  intussusceptum  stimulates  the 
enclosing  intussuscipiens  to  painful  straining  to  stool  (tenesmus),  and  a 
discharge  of  bloody  mucus  from  the  anus  results.  Occasionally  the 
intussusceptum  itself  is  passed,  after  sloughing. 

On  section  an  intussusception  is  found  to  consist  of  three  cylinders  of 
bowel,  two  of  which  belong  to  the  prolapsed  part,  or  intussusceptum, 
and  one  to  the  containing  part,  or  intussuscipiens.  A  rare  form,  double 
intussusception,  consists  of  five  cylinders.  The  serous  surfaces  of  the 
intussusceptum  are  in  contact  with  one  another  and  are  liable  to  form 
adhesions.  The  mesentery  is  compressed  between  these  surfaces  on  one 
side,  and  this  pressure  is  apt  to  cause  venous  congestion,  edema,  and 
finally,  strangulation  and  gangrene,  with  perforation  or  sloughing  of  the 
intussusceptum.  In  such  cases  the  invaginated  bowel  may  slough  off 
and  be  passed  per  anum,  and  a  spontaneous  recovery  result.  Between 
the  intussusceptum  and  the  intussuscipiens  the  mucous  surfaces  are  in 
contact. 

The  appendix  vermiformis  is  a  narrow,  cylindrical,  blind  tube,  which 
represents  the  rudimentary  or  atrophied  lower  end  of  the  larger  cecum 
of  many  other  animals.  Even  in  the  human  fetus  it  is  seen  to  be  merely 
the  narrowed  extremity  of  a  capacious  cecum.  Like  other  vestigial  'parts, 
it  is  prone  to  inflammation,  which  tends  to  cause  its  obliteration,  a  pro- 
cess which  evolution  would  appear  to  be  slowly  bringing  about. 

Its  length  varies  between  10  mm.  (f  in.)  and  24  cm.  (9^  in.),  and 
averages  about  8.5  cm.  (3^  in.).  It  attains  its  greatest  length  in  early 
adult  life  (twenty  to  forty  years,  Berry),  after  which  it  shrinks  somewhat. 
Its  length  bears  no  relation  to  the  size  of  the  cecum.  In  a  few  authentic 
cases  it  has  been  reported  wanting.  When  this  condition  is  apparently 
disclosed  at  an  operation,  the  fact  should  be  accepted  with  doubt,  for  its 
presence  may  not  be  apparent  without  thorough  and  careful  dissection, 
when  it  occupies  certain  irregular  positions.  Its  diameter  is  about  6  mm. 
(\  in.)  at  the  base  and  5  mm.  {\  in.)  at  the  apex,  but  in  old  age  it  may 
become  still  smaller.  The  longer  the  appendix  the  greater  the  difficulty, 
other  things  being  equal,  of  the  egress  of  a  solid  or  semisolid  body  from 
the  distal  end.  With  a  long  narrow  process  the  conditions  are  favor- 
able to  the  stagnation  of  its  contents,  which  predisposes  to  inflammation. 

The  length  and  the  size  of  its  lumen  is  of  more  practical  interest.  The 
diameter  of  the  lumen  varies  in  different  parts  between  that  of  a  fine 
probe  and  that  of  a  quill,  and  the  average,  according  to  Ferguson,  is  that 
of  a  No.  9  sound  of  the  English  scale.  A  variable  point  is  the  opening 
into  the  cecum,  ranging  from  a  mere  pinhole  to  a  No.  7  catheter  (English 
scale).  It  is  often  guarded  by  a  valve  or  a  prominence  of  mucous  mem- 
brane due  to  an  increase  of  lymphoid  tissue  beneath  it.  This  is  especially 
so  in  childhood,  and  it  may  decrease  or  disappear  later.  The  size  of  the 
opening  here  is  important,  for  a  small  opening  admits  fluid  feces  and 


THE  ABDOMINAL  VISCERA  349 

prevents  or  hinders  the  escape  of  semisolid  material.  A  valve  was 
described  by  Gerlach,  guarding  the  appendicocecal  orifice  and  so  directed 
as  to  cause  retention  of  the  appendical  contents,  but  its  existence  is  now 
doubted. 

In  about  25  per  cent,  of  cases  the  lumen  is  partially,  less  often  com- 
pletely, obliterated,  commencing  with  the  distal  end.  It  is  a  physio- 
Joqieal  not  a  pathological  process.  Very  little  (4  per  cent.)  of  this  oblitera- 
tion is  found  in  the  first  ten  years  of  life,  while  it  is  present  in  over  50 
per  cent,  of  cases  at  sixty  years.  The  obliteration  of  the  lumen  at  its 
distal  end  shortens  it.  The  lumen  may  also  be  found  stenosed  irregularly 
here  and  there,  as  the  result  of  previous  attacks  of  inflammation  (appen- 
dicitis), and  these  stenoses  favor  recurrence  of  inflammation  by  inter- 
fering with  the  proper  emptying  of  the  appendix.  The  presence  of  the 
obliteration  of  its  lumen  cannot  be  told  by  the  macroscopic  external 
appearance  of  the  appendix. 

The  appendix  is  held  in  position  (1)  by  the  attachment  of  its  base  to  the 
cecum  (see  cecum);  (2)  by  a  mesentery  of  its  own  (mesenteriolum). 
The  base  of  the  appendix,  and  with  it  the  appendix  itself,  varies  in 
position  with  that  of  the  cecum.  Thus  it  may  be  unusually  high  when 
the  cecum  is  partly  or  wholly  undescended  (see  cecum). 

The  mesentery  of  the  appendix  (meso-appendix  or  mesenteriolum)  is 
derived  from  the  lower  or  left  layer  of  the  mesentery,  along  a  straight 
line  a  short  distance  below  the  bowel,  and  not  quite  parallel  with  it.  It 
represents  a  fold  of  peritoneum  raised  up  by  the  artery  in  its  passage  from 
the  back  of  the  ileum  to  the  appendix.  It  is  triangular  in  shape,  with  its 
apex  at  the  base  of  the  appendix  and  one  side  attached  to  the  abdominal 
wall,  or  the  mesentery,  the  other  to  the  appendix,  while  the  fbase  is 
free.  The'mesenteriolum  extends  to  the  tip  of  the  appendix  in  fully 
one-half  of  the  cases  (Monks  and  Blake),  and  in  the  remaining  cases 
about  half-way,  so  that^the  terminar'portion  is  either  wholly  covered 
by  peritoneum  or  it  possesses  a  narrow  fringe  of  peritoneum  continuous 
with  the  mesentery.  The  appendical  border  of  the  meso-appendix  is 
longer  than  its  parietal  border,  which  partly  accounts  for  the  tortuous  or 
coiled  position  of  the  appendix,  similar  to  that  of  the  small  intestine, 
and  due  to  the  same  cause.  An  ample  mesentery  affords  some  security 
against  attacks  of  appendicitis  by  avoiding  undue  angulation  of  and 
traction  or  pressure  upon  the  vessels,  which  run  between  its  folds. 

The  appendix  is,  therefore,  an  intraperitoneal  organ,  wholly  covered 
by  peritoneum  except  for  a  narrow  strip  along  the  attachment  of  its 
mesentery.  Hence  inflammation  of  the  appendix  (appendicitis)  is  an 
intraperitoneal  inflammation,  unless  walled  ofl"  by  adhesions  and  plastic 
exudate.  Tn  exceptional  rases  the  appendix  is  in  whole  or  in  part  extra- 
peritoneal. Thus  it  may  li<-  behind  (he  cecum,  adherent  to  its  wall  and 
covered  by  its  peritoneum,  or  its  distal  portion  only  may  be  extraperi- 
toneal, behind  die  colon,  while  its  proximal  part  is  intraperitoneal,  or 
vice  rersa.  Probably  some  of  the  cases  reported  as  extraperitoneal  were 
really  instances  of  the  appendix  herniated  into  and  adherent  to  the 
ileocecal  or  subcecal  to 


350  THE  ABDOMEN 

As  a  result  of  inflammation  the  appendix  may  contract  adhesions  to 
the  visceral  or  parietal  peritoneum  with  which  it  is  in  contact.  These 
adhesions  vary  from  a  single'  delicate  one  to  those  completely  binding 
down  the  entire  length  of  the  appendix.  The  latter  condition  is  not 
infrequently  found  in  operating  for  appendicitis.  I  have  found  the  tip 
separated  from  the  rest  and  only  connected  with  it  by  scar  tissue,  repre- 
senting a  necrotic  area  of  the  tube.  In  removing  an  appendix  closely 
adherent  to  the  posterior  parietes  and  directed  inward  the  relation  of  the 
ureter  and  the  iliac  vessels  should  be  borne  in  mind.  When  adherent  to 
the  ileum  it  may  even  form  a  constricting  band  about  it,  or  a  bridge  may 
be  formed  beneath  which  the  small  intestine  may  be  strangulated. 

It  is  stated  (Clado)  that  in  1  case  in  10  in  females  there  is  a  process  of 
peritoneum  passing  from  the  right  ovary  to  the  meso-appendix  (appen- 
diculoovarian  ligament),  which  contains  lymphatics  and  a  small  artery 
forming  an  anastomosis  between  the  appendicular  and  ovarian  vessels. 
It  has  also  been  suggested  that  theoretically  this  anastomotic  circulation 
would  confer  a  certain  immunity  against  appendicitis,  by  preventing 
congestion  and  avoiding  gangrene. 

In  position  the  appendix,  though  tortuous,  has  a  principal  direction 
from  base  to  apex,  and  is  said  to  "point"  this  way  or  that.  It  may  point 
in  any  direction,  like  the  needle  of  a  compass  or  the  hands  of  a  watch, 
and  its  direction  is  sometimes  indicated  by  the  points  of  the  compass.  A 
great  number  of  observations  have  been  reported  as  to  the  direction  of 
the  appendix  by  different  observers  and  with  varying  results.  There  are 
two  main  positions  of  the  appendix:  one  upward  behind  the  cecum,  the 
other  downward  away  from  the  cecum.  Both  of  these  main  positions  may 
be  modified  by  a  lateral  deviation  to  the  right  or  left.  Thus  the  appendix 
may  point  upward  and  to  the  right,  and  lie  to  the  outside  of  the  cecum 
and  colon,  or  it  may  point  upward  and  to  the  left,  lying  below  the  mesen- 
tery and  the  lower  end  of  the  ileum.  Again,  when  it  points  downward  it 
may  lie  along  the  pelvic  brim  or  project  into  the  pelvis.  The  order  of 
frequency  is  (1)  retrocecal;  (2)  pelvic  (i.  e.,  down  and  in);  (3)  upward  and 
inward;  (4)  variable.  The  upturned  appendix  is  probably  to  be  explained 
by  adhesion  of  its  distal  end  in  its  descent  from  its  fetal  position  beneath 
the  liver,  the  down-turned  appendix  by  the  absence  of  such  adhesions. 
It  will  be  observed  from  the  above  that  the  appendix  is  mostly  in  the  right 
lumbar,  the  hypogastric,  or  the  umbilical  regions,  and  more  rarely  in  the 
right  iliac  region,  though  it  usually  lies  in  part  or  wholly  in  the  right  iliac 
fossa. 

Its  curved  or  spiral  course  is  due  to  its  short  mesentery,  or,  in  other 
words,  to  its  growth  between  points  fixed  at  an  early  date.  The  most 
fixed  point  is  where  the  postcecal  branch  of  the  ileocolic  artery  joins  it; 
another  fixed  point  is  where  the  fusion  between  the  non-vascular  fold  and 
the  posterior  vascular  fold  (meso-appendix)  terminates. 

The  relations  of  the  appendix  to  the  anterior  abdominal  wall  are  most 
important  for  clinical  purposes.  Both  for  diagnosis  and  operation 
McBurney's  point  is  the  one  most  commonly  used.  This  is  a  point  on  the 
line  between  the  anterior  superior  iliac  spine  and  the  umbilicus  6.7  cm. 


THE  ABDOMINAL  VISCERA  351 

(2h  in.)  from  the  iliac  spine.  It  lies  in  the  right  lumbar  region  and  is  a 
guide  not  to  the  position  of  the  appendix  itself,  which  is  very  mobile,  but 
?o  its  base.  Though  this  varies  with  the  position  of  the  cecum  in  the 
great  majoritv  of  cases  it  will  lie  somewhere  beneath  a  circle  5  cm. 
(2  in.)  in  diameter,  having  this  point  as  its  centre.  Within  the  same 
area  will  be  the  point  of  greatest  tenderness  in  appendicitis,  but  undue 
value  should  not  be  given  to  the  exact  point.  Clado  locates  the  guiding 
point  lower  down  on  a  level  with  the  anterior  superior  iliac  spine  at  the 
outer  border  of  the  rectus. 

The  walls  of  the  appendix  present  the  same  layers  as  those  of  the  cecum 
and  colon.  We  have  already  studied  the  peritoneal  covering.  The 
muscular  fibers  are  largely  replaced  by  fibrous  tissue.  The  existence  of 
longitudinal  muscle  fibers  is  seen  in  the  rapid  shortening  of  the  appendix 
after  removal,  sometimes  by  one-third  of  its  length.  It  is  spread  out 
uniformly  and  not  arranged  in  bands  as  in  the  cecum  and  colon.  The 
circular  muscular  fibers  are  demonstrated  by  the  peristaltic  movements 
of  the  appendix  that  are  sometimes  observed,  by  cases  of  so-called  appen- 
diceal colic,  and  by  their  retraction  so  as  to  expose  the  mucosa  after 
lengthwise  incisions.  This  layer  may  form  about  one-third  of  the  thick- 
ness of  the  appendical  wall.  The  submucosa  is  a  thick  layer  of  dense 
areolar  tissue  containing  many  solitary  lymph  follicles,  which  are  more 
abundant  here  and  in  the  cecum  than  elsewhere  in  the  large  intestine. 
They  are  also  more  numerous  in  early  life,  up  to  the  twentieth  or  thir- 
tieth year,  after  which  they  normally  atrophy  more  or  less.  Where  the 
lumen  is  obliterated  the  mucous  glands  of  the  mucosa  are  found  to  have 
disappeared,  while  the  other  parts  remain.  The  mucosa  is  also  rich  in 
lymphoid  tissue.  Abundance  of  lymphoid  tissue  is  a  marked  feature  of 
the  appendix,  and  here,  as  elsewhere,  it  is  prone  to  inflammation,  espe- 
cially in  early  life,  when  it  is  in  greatest  abundance.  This  corresponds 
with  the  known  greater  frequency  of  appendicitis  in  early  life. 

The  distal  end  of  the  appendix  is  thick  and  fibrous.  The  presence  of 
fecal  concretions  in  the  lumen  of  the  appendix  is  quite  common.  They 
may  lead  to  inflammation  and  perforation  of  the  appendix,  but  by  no 
meana  necessarily  cause  appendicitis,  for  we  often  find  them  postmortem 
without  sigD  or  history  of  appendicitis,  yet  in  cases  of  appendicitis  they 
are  present  in  considerably  over  50  per  cent,  of  cases.  Although  foreign 
holies  may  be  found  in  the  appendix,  they  are  an  infrequent  cause  of 
appendicitis,  :ts  compared  with  other  causes. 

The  swelling  of  the  mucosa  in  inflammation  tends  to  narrow  or  entirely 
dose  the  lumen  at  points  already  narrowed  by  stenoses,  valves,  or  dupli- 
catures  of  mucous  membrane,  or  by  twists  or  kinks  in  the?appendix. 
\   the  appendix  is  contractile  but  not  extensible, il  is  thus  pul  to  great 

in  toexpel  itSCOntentS.  The  pressure  on  its  walls,  or,  more  often,  the 
infection  and  inflammation  of  them  from  within,  cause  venous  conges- 
tion.     Thi      result!     in    .welling,  which,  unless    relieved,  goes  on   to  the 

complete   translation  orobstruction  of  the  vessels,  and  gangrene  results. 
It'  a  concretion  i    pre  enl  as  an  additional  obstructing  or  compressing 

i,t,  local  gangrene  i   even  more  likely. 


352 


THE  ABDOMEN 


Vessels  and  Nerves. — The  appendix  is  supplied  by  the  postcecal 
branch  of  the  ileocolic  artery.  The  main  or  distal  branch  reaches  the  appen- 
dix by  passing  along  the  free  border  of  the  meso-appendix,  between  its 
folds.  The  proximal  branch  passes  to  the  root  of  the  appendix.  Excep- 
tionally the  artery  passes  directly  to  the  tip  of  the  appendix  without 
branching  and  then  runs  back  toward  its  base.  In  such  a  case  the  stasis 
of  its  blood  current,  from  pressure,  etc.,  at  the  tip,  would  involve  the 
entire  appendix  in  gangrene.  Local  blood  stasis  due  to  inflammatory 
or  mechanical  pressure  is  the  cause  of  local  gangrene  of  the  appendix. 

Fig.  119 


ILEOC/ECAL 


ANTERIOR 
LYMPHATICS 
OF  CECUM 


GLAND  OF 
APPENDIX 


Anterior  view  of  the  lymphatics  of  the  cecum,  and  appendix.      (Poirier  and  Charpy.) 


The  lymphatics  accompany  the  artery  and  enter  the  ileocecal  group  of 
mesenteric  nodes,  after  traversing  some  small  nodes  in  the  meso- 
appendix  just  behind  or  below  the  ileum  or  against  the  cecum,  above  the 
root  of  the  appendix.  The  node  or  nodes  in  the  meso-appendix  may  be 
enlarged  or  even  broken  down  in  appendicitis. 

The  nerves  supplying  the  appendix  come  from  the  superior  mesenteric 
plexus,  which  also  supplies  the  small  intestine  and  the  large  intestine  as 
far  as  the  splenic  flexure.  Hence  the  explanation  of  the  fain  in  appen- 
dicitis being  commonly  referred  at  first  to  the  abdominal  nerve  centres 
in  the  epigastric  or  umbilical  regions. 

Pericecal  Fossae  (Figs.  118,  119). — There  are  a  number  of  peritoneal 
pouches  or  fossae  in  the  ileocecal  region  which  deserve  notice  because  into 
them  the  bowel,  and  especially  the  appendix,  may  be  herniated. 


THE  ABDOMINAL  VISCERA  353 

The  upper,  or  ileocolic  fossa, lies  just  above  the  ileocolic  junction,  and  is 
bounded  on  the  sides  by  the  ileum  and  the  colon,  and  in  front  by  the 
fold  of  peritoneum  formed  by  the  passage  across  the  ileocolic  angle  of  a 
branch  of  the  ileocolic  artery.  It  opens  downward,  but  is  too  high  to 
concern  the  appendix,  and  is  also  less  important  than  the  following, 
because  it  is  smaller  and  less  constant. 

The  ileocecal  fossa  is  exposed  by  turning  up  the  cecum  and  drawing 
the  appendix  down  and  the  ileum  up.  It  is  bounded  on  the  right  by  the 
cecum,  on  the  left  by  the  small  intestine,  in  front  by  the  ileocecal  "blood- 
less" fold  which  passes  from  the  ileum  to  the  meso-appendix,  which 
bounds  it  behind.  It  opens  downward  and  outward,  is  almost  constant, 
and  is  large,  admitting  two  fingers.  It  is  to  be  remembered  that  the 
appendix  is  often  found  in  this  fossa,  which  makes  it  of  practical  impor- 
tance. The  appendix  so  placed  may  be  thought  to  be  extraperitoneal  or 
even  to  be  absent,  hence  we  should  look  for  this  fossa  and  feel  behind 
the  cecum  and  colon  when  the  appendix  is  not  readily  found. 

The  retrocolic  fossce,  external  and  internal,  are  occasionally  present 
behind  the  ascending  colon.  On  raising  the  cecum  they  are  seen  to  open 
downward,  when  present,  and  are  likely  to  lodge  the  distal  end  of  the 
appendix. 

The  Colon.— The  large  intestine  (Figs.  109,  114,  123,  128),  from  the 
tip  of  the  cecum  to  the  point  where  the  mesorectum  ends,  opposite  the 
third  sacral  vertebra,  averages  140  cm.  (4|  ft.)  in  length  in  the  male,  and 
5  cm.  (2  in.)  less  in  the  female.  Its  diameter  decreases  from  above 
downward,  measuring  3.5  cm.  (1^  in.)  at  the  lower  end  of  the  sigmoid 
flexure  and  7.5  cm.  (3  in.)  in  the  cecum.  It  varies  with  the  fulness  or 
emptiness  of  the  gut,  which  is  liable  to  enormous  dilatation,  if  this  is 
gradually  produced.  In  some  cases  of  intestinal  obstruction,  situated  low 
down,  the  accumulation  of  feces  and  gas  may  so  distend  the  colon  that 
it  occupies  most  of  the  abdomen,  displaces  the  heart  and  lungs  upward, 
and  causes  shortness  of  breath  and  palpitation  of  the  heart,  which  can  be 
relieved  only  by  emptying  the  bowel.  Dilatation  of  the  colon  may  occur 
among  rachitic  infants,  temporarily;  or  it  may  be  associated  with  hyper- 
trophy of  the  bowel  wall,  constipation,  and  abdominal  distention.  On 
the  oilier  hand,  the  colon  is  liable  to  be  the  seat  of  stricture,  cicatricial 
or  malignant.  The  tendency  to  the" latter  increases  from  above  down- 
ward, being  most  common  at  the  narrowest  part,  i.  e.,  the  junction  of  the 
sigmoid  flexure  and  the  rectum,  and  least  common  in  (lie  ascending  colon. 
The  flextures  of  the  colon  are  also  a  favorite  situation  for  stricture.  Tuber- 
culous  inflammation, with  induration,  thickening, and  stricture, occurs  in 
the  colon  as  well  as  in  the  ileocecal  region.  The  percussion  note  of  the 
colon  is  of  a  higher  pitch  than  (hat  of  the  stomach  and  lower  than  that  of 
the  small  intestine,  owing  to  the  difference  in  size  and  in  the  thickness 
of  the  walls.  Dulness  on  percussion  in  (he  flanks,  disappearing  when 
the  patient  is  turned  on  the  side,  may  be  due  to  an  abundance  of  fluid 
in  the  colon. 
Capacity.  Th<-  colon  of  an  infant  six  months  old  holds  one  pint  (500 
c.c),  thai  <>f  ;i  child  two  years  old,  two  to  three  pints  (1000  to  1500  c.c.), 


354  THE  ABDOMEN 

and  that  of  an  adult  nine  pints  (4500  c.c).  It  is  useful  to  remember  these 
figures  in  irrigating  the  colon.  No  attempt  should  be  made  to  force 
fluid  above  the  large  intestine.  The  irrigation  of  the  colon  empties  the 
lower  ileum  by  exciting  active  peristalsis.  Large  amounts  of  fluid  may 
be  absorbed  by  the  colon  when  injected  under  slight  pressure,  15  cm. 
(6  in.)  in  an  enteroclysis.  The  colon  is  so  arranged  as  to  surround  the 
small  intestine  in  a  circuit  from  right  to  left. 

The  colon  is  characterized  by  (1)  three  longitudinal  bands  or  teniae 
separating  (2)  three  rows  of  alternating  sacculi  (haustra)  and  constric- 
tions (plicae);  (3)  the  appendices  epiploicae.  Of  the  three  longitudinal 
bands  or  teniae,  the  one  along  the  anterior  surface  is  the  longest  and  most 
prominent.  As  they  start  from  the  base  of  the  appendix  this  anterior 
band  is  most  useful  in  helping  us  to  find  the  latter.  They  measure  about 
12  mm.  (|-  in.)  in  width  and  are  about  half  as  long  as  the  actual  length 
of  the  large  intestine.  Accordingly  they  pucker  up  the  intervening 
intestinal  walls  into  three  rows  of  pouches  or  sacculi,  alternating  with 
constrictions,  so  that  if  these  bands  be  dissected  off,  the  gut  will  be  made 
much  longer  and  of  uniform  contour.  They  disappear  in  the  lower  part 
of  the  sigmoid  flexure. 

Between  the  three  bands  the  longitudinal  fibers  are  sparingly  present, 
hence  the  walls  of  the  sacculi  and  plica?  are  made  up  of  all  layers.  The 
anterior  and  inner  of  these  bands  are  useful  in  operations  to  distinguish 
the  large  from  the  small  intestine.  As  these  bands  are  conspicuous  only 
when  covered  by  peritoneum,  the  posterior  one  along  the  attached  border 
is  of  little  use  as  a  guide  in  the  retroperitoneal  lumbar  operations  (lumbar 
colotomy,  etc.).  In  cases  of  very  great  distention  the  teniae,  as  well  as  the 
sacculi,  are  temporarily  less  noticeable  or  even  effaced.  In  such  a  case 
we  can  recognize  the  large  intestine  by  the  presence  of  the  third  char- 
acteristic, the  appendices  epiploicae.  These  are  small  pouches  or  tassels 
of  peritoneum  containing  more  or  less  fat  and  attached  to  the  peritoneal 
covering  of  the  large  bowel,  except  the  lower  rectum.  They  are  seen 
especially  along  the  internal  band,  and  are  most  numerous  in  the  lower 
part.  They  therefore  afford  no  help  in  identifying  the  colon  through  the 
loin,  along  its  attached  or  non-peritoneal  area.  The  lesser  mobility, 
larger  size,  and  the  absence  of  the  palpable  ridges  due  to  the  valvulae 
conniventes  also  help  in  identifying  the  colon. 

Solitary  lymphoid  follicles  are  most  numerous  in  the  cecum  and  appen- 
dix, and  occur  throughout  the  large  intestine.  Hernia-like  diverticula, 
usually  multiple,  may  occur  throughout  the  colon.  They  may  sometimes 
lodge  fecal  concretions,  and  by  ulceration  and  perforation  (diverticu- 
litis) become  the  cause  of  peritonitis. 

The  large  intestine  is  palpable  throughout  except  at  and  near  the 
flexures  which  are  deeply  placed.  In  the  lumbar  regions  also  the  colon, 
unless  distended,  lies  well  back  and  is  covered  by  coils  of  the  small  intes- 
tines. Hence,  save  at  the  flexures,  tumors  of  the  colon,  even  when  of 
moderate  size,  can  be  well  made  out,  the  progress  along  the  colon  of  an 
intussusception  can  often  be  carefully  watched,  as  well  as  the  effects  of 
the  injection  of  fluid  or  gas  for  its  reduction.    The  outline  of  the  colon  in 


THE  ABDOMINAL  VISCERA  355 

cases  of  fecal  accumulation  can  also  be  distinctly  defined.  In  distention 
of  the  large  intestine  from  any  cause  the  front  of  the  belly  is  often  com- 
paratively flat,  as  long  as  the  distention  is  not  excessive  and  is  confined  tothe 
large  bowel,  while  the  two  sides  and  the  region  just  above  the  umbilicus  are 
prominent.     The  reverse  is  the  case  in  distention  of  the  small  intestine. 

Vessels  and  Nerves. — The  colic  branches  of  the  superior  mesenteric 
artery  supply  as  far  as  the  splenic  flexure  (the  end  of  the  midgut)  and, 
in  the  left  part  of  the  transverse  colon,  anastomose  with  the  branches  of 
the  inferior  mesenteric  artery,  which  supplies  the  large  intestine  below  this 
point.    The  veins  enter  the  portal  circulation. 

The  lymphatic  vessels  of  the  ascending,  transverse,  and  descending 
colon  enter  the  mesenteric  nodes,  those  of  the  sigmoid  flexure  the  inferior 
mesenteric  group  of  pre-aortic  nodes.  All  the  lymphatics  entering  the 
above  nodes  have  first  traversed  small  nodes  accompanying  the  arterial 
branches  which  pass  to  the  intestine. 

The  nerves  are  from  the  sympathetic  plexuses  and  accompany  the 
arteries.  Those  which  supply  the  cecum,  ascending  colon,  and  right  half 
of  the  transverse  colon  come  through  the  superior  mesenteric  plexus 
from  the  celiac  plexus ;  while  those  supplying  the  left  half  of  the  transverse 
colon,  the  descending  and  the  sigmoid  colon,  come  through  the  inferior 
mesenteric  plexus  from  the  aortic  plexus. 

The  Ascending  and  Descending  Colons. — The  ascending  colon  and 
descending  colon  are  vertically  placed  in  the  lumbar  and  hypochondriac 
regions  in  front  of  the  lateral  border  of  the  quadratus  lumborum  and  of 
the  lower  part  of  the  right  kidney  and  the  lower  part  of  the  outer  border 
of  the  left  kidney.  Hence  abscess  of  the  kidney  may  perforate  the  colon 
retroperitoneally.  The  guide  to  the  colon  by  the  lumbar  approach  is  the 
outer  border  of  the  quadratus  lumborum  muscle,  below  the  kidney.  The 
second  portion  of  the  duodenum  is  to  the  inner  side  of  the  ascending  colon. 
The  descending  colon  is  more  laterally  placed  than  the  ascending,  and  hence 
is  more  accessible  through  the  loin.  The  ascending  colon  averages  12.5 
cm.  (5  in.)  from  the  ileocecal  valve  to  the  under  surface  of  the  right  lobe 
of  the  liver  (impressio  colica),  on  the  right  of  the  gall-bladder.  The 
descending  colon  averages  21  cm.  (8$  in.)  to  the  iliac  crest,  the  com- 
mencement  of  th<-  sigmoid  loop. 

A  mesentery,  varying  from  2.5  to  7.5  cm.  (1  to  3  in.)  in  length,  is  pro- 
vided for  the  ascending  colon  in  only  20  per  cent,  of  eases,  and  for  the 
descending  colon  in  36  per  cent.  (Treves) ;  in  the  oilier,  74  or  64  per  cent, 
respectively,  the  peritoneum  covers  the  front  and  sides  only,  leaving  a 
wide  strip  uncovered  posteriorly.  This  strip  varies  in  width,  averages 
one-third  of  the  circumference  of  the  colon,  and  is  wider  the  more  dis- 
tended the  colon  becomes,  ft  is  here  that  the  colon  was  opened  in  lumbar 
colotomy,  hence  the  presence  of  a  mesentery  was  of  importance  in  eon- 
neciion  with  this  operation,  especially  in  the  case  of  the  descending  colon, 
which  w;i  the  portion  most  often  opened.  Along  this  strip  (he  back  of  the 
colon  is  in  relation  with  the  loose  subperitoneal  tissue  in  which  a  retro- 
colic  ;il>  cess  may  form, secondary  to  inflammation  of  a  high  retrocolic 
appendix  or  of  the  colon  it  ielf. 


356  THE  ABDOMEN 

The  ascending  colon  may  be  absent  when  the  cecum  has  not  descended, 
but  the  descending  colon  shows  but  little  tendency  to  variation  and  is  the 
only  part  of  the  gut,  below  the  duodenum,  that  retains  its  original  vertical, 
fetal  position. 

The  Transverse  Colon. — The  transverse  colon  averages  50  cm.  (20  in.) 
in  length,  but  is  very  variable.  As  it  is  longer  than  a  straight  line  between 
its  two  ends,  it  describes  a  curve  convex  forward  and  downward.  As  a 
rule,  it  lies  above  the  level  of  the  umbilicus,  but  in  29  per  cent,  of  cases  it 
is  below  this  line,  and  in  some  cases  it  is  displaced  downward  in  an  abrupt 
V-  or  U-shaped  bend,  which  may  even  reach  the  symphysis,  while  the  two 
flexures  are  normal  in  position.  Such  bends  are  due  to  habitual  constipa- 
tion or  to  congenital  causes  (Treves).  In  the  majority  of  cases  the 
central  portion  of  the  transverse  colon  is  in  the  line  separating  the 
epigastrium  from  the  umbilical  region. 

Relations. — Above  is  the  under  surface  of  the  liver,  the  gall-bladder, 
the  great  curvature  of  the  stomach,  and  the  lower  end  of  the  spleen; 
behind  is  the  second  part  of  the  duodenum,  the  pancreas,  and  the  trans- 
verse mesocolon;  below  is  the  small  intestine,  and  in  front  the  great 
omentum  and  anterior  abdominal  wall. 

The  transverse  colon  always  has  a  mesentery  {mesocolon)  (Fig.  115), 
which  from  its  length  renders  this  the  most  movable  'portion  of  the  colon, 
hence  it  is  often  found  in  the  sac  of  an  umbilical  hernia.  Its  anterior 
surface  along  the  anterior  band  is  adherent  to  the  great  omentum,  which 
separates  it  from  the  anterior  abdominal  walls.  Through  the  omentum 
the  sacculi  of  the  colon  can  usually  be  seen.  By  raising  up  the  omentum 
we  expose  the  transverse  colon  adherent  to  it.  This  portion  of  the  colon 
and  the  omentum  shut  in  the  coils  of  the  small  intestine  above  and  in 
front  respectively.  The  part  of  the  omentum  between  the  great  curva- 
ture of  the  stomach  and  the  transverse  colon  {gastrocolic  ligament)  con- 
nects the  two,  so  that  the  latter  moves  with  the  stomach.  It  overlies  the 
latter  when  it  is  empty,  and  is  pushed  down  by  it  when  it  is  full.  Many 
errors  in  diagnosis  are  attributable  to  fecal  masses  impacted  in  the  trans- 
verse colon. 

Owing  to  the  close  relation  of  the  hepatic  flexure  and  the  right  end  of  the 
transverse  colon  with  the  gall-bladder,  ulceration  of  the  latter,  due  to 
gallstones,  has  sometimes  involved  the  adherent  colon,  and  the  gall- 
stone has  thus  entered  the  colon  and  been  passed  per  anum.  It  is  often 
found  stained  with  bile  postmortem.  If  the  gall-bladder  cannot  be 
approximated  to  the  duodenum  or  jejunum  in  cholecystenterostomy, 
the  anastomosis  can  be  readily  made  with  the  colon,  and  the  short- 
circuiting  of  the  bile  has  had  no  untoward  effect  on  the  patient's  con- 
dition. Hepatic  abscess  has  also  ruptured  into  and  been  discharged 
through  this  part  of  the  colon.  I  have  also  seen  a  fistulous  opening 
between  the  transverse  colon  and  the  stomach  in  case  of  a  carcinoma  of 
the  latter. 

The  splenic  flexure,  at  the  left  end  of  the  transverse  colon,  is  in  contact 
with  the  lower  end  of  the  spleen  in  the  left  hypochondrium.  It  lies  behind 
the  stomach  and  is  higher  and  more  dorsal  than  the  hepatic  flexure. 


THE  ABDOMINAL  VISCERA  357 

Both  flexures  of  the  colon,  deeply  placed  at  the  back  of  the  hypo- 
chondriac regions,  are  held  by  bands  of  'peritoneum  passing  from  the 
hepatic  flexure  to  the  under  surface  of  the  liver  (Jig.  hepatocolicum, 
Joessel),  an  inconstant  expansion  of  the  hepatoduodenal  ligament, 
and  from  the  splenic  flexure  to  the  diaphragm  opposite  the  tenth  and 
eleventh  ribs  {lig.  phrenocolicum).  The  latter,  derived  from  the  left  end  of 
the  great  omentum,  is  also  called  the  sustentaculum  lienis,  as  it  helps  to 
support  the  spleen. 

The  Sigmoid  Colon  or  Flexure. — The  sigmoid  colon  or  flexure  extends 
from  the  level  of  the  left  iliac  crest  to  the  third  sacral  vertebra  at  the  end 
of  the  mesenteric  attachment,  including  the  part  formerly  called  the  first 
piece  of  the  rectum.  Including  the  latter  it  forms  an  U-shaped  loop 
averaging  44  cm.  (17^  in.)  long.  The  sigmoid  flexure  is  normally  found 
in  great  part  in  the  pelvis  and  not  in  the  iliac  fossa,  unless  displaced  out 
of  the  pelvis  by  its  own  distention  or  that  of  the  bladder,  rectum,  or 
female  pelvic  organs,  with  which,  as  well  as  with  the  small  intestine  and 
often  with  the  appendix  or  even  the  cecum,  it  is  in  relation  in  the  pelvis, 
and  to  which  it  may  become  adherent  in  pelvic  inflammation.  If  the 
mesentery  of  the  sigmoid  colon  is  unusually  short,  the  latter  may  be  very 
largely  in  the  left  iliac  fossa.  The  division  of  the  sigmoid  colon  into  the 
iliac  and  pelvic  colon  (Jonnesco),  according  as  it  lies  above  or  below 
the  pelvic  brim,  serves  no  useful  purpose,  and  the  portions  of  the  loop 
in  the  iliac  fossa  and  pelvis  vary  constantly  with  the  condition  of  the 
pelvic  viscera,  etc.  This  loop  is  liable  to  enormous  dilatation  from  fecal 
accumulation,  and  has  been  known  to  reach  up  to  the  liver. 

In  the  newborn  the  sigmoid  loop,  usually  filled  with  meconium,  may 
reach  over  to  the  right  side,  owing  to  its  long  mesentery.  Under  such 
conditions  the  opening  of  this  loop  in  the  left  groin  to  establish  an  arti- 
ficial anus,  which  is  required  in  cases  of  congenital  deficiency  of  the 
rectum,  might  be  difficult.  Yet,  according  to  Curling,  it  is  found  on  the 
left  side  in  85  per  cent,  of  cases  in  young  infants. 

The  sigmoid  loop  is  provided  with  a  constant  mesentery,  3  to  8.5  cm. 
(1^  to  3£  in.)  long,  from  parietal  to  intestinal  attachments,  which  connects 
it  with  the  left  iliac  fossa.  The  line  of  attachment  of  this  mesentery 
<i..sses  the  psoas  muscle  to  reach  the  pelvic  brim  at  about  the  bifurcation 
of  the  left  common  iliac  vessels  and  the  sacro-iliac  articulation,  or  a  little 
above  it.  Then  it  turns  sharply  downward  and  extends  to  the  middle  of 
the  third  sacral  vertebra.  The  two  attached  extremities  of  this  loop  are 
only  7..">  or  10  cm.  (3  or  4  in.)  apart,  and  may  be  nearer  abnormally. 
Hence,  since  the  loop  itself  is  fairly  movable,  the  conditions  are  such  that 
we  can  easily  sec  how  a  twist  or  volvulus  may  occur,  as  it  does,  more 
often  in  this  portion  of  the  bowel  than  in  any  other. 

On  the  left  or  lower  aspect  of  the  root  of  the  sigmoid  mesocolon  is 
oftentimes  b  peritoneal  pouch,  the  intersigmoid  fossa,  in  which  the  occur- 
rence  of  at  least  two  cases  of  strangulated  sigmoid  hernia  has  been 
reported.  Tlii  fossa  is  funnel-shaped,  ;in<l  its  opening  looks  downward 
and  to  the  left,  and  is  generally  over  the  bifurcation  of  the  iliac  vessels. 
1 1  ;is  found  by  turning  the  flexure  to  the  right.    The  fossa  is  2.5  to  6  cm. 


358  THE  ABDOMEN 

(1  to  2\  in.)  deep,  is  more  constant  in  the  infant  than  in  the  adult,  and  is 
caused  by  a  fold  due  to  the  sigmoid  artery. 

The  rectal  or  colon  tube  cannot  be  passed  beyond  the  sigmoid  loop 
under  normal  conditions,  but  the  irrigation  of  the  colon  can  be  accom- 
plished with  the  tube  in  this  loop.  In  case  of  habitual  constipation  a 
doughy  tumor  may  be  present  in  the  sigmoid  colon.  Such  tumors,  and 
those  of  other  kinds  in  this  part  of  the  bowel,  may  press  upon  the  branches 
of  the  left  lumbar  plexus,  such  as  the  anterior  crural  or  obturator, 
and  cause  neuralgia.  The  sigmoid,  descending  and  ascending  colon, 
as  well  as  the  cecum  may  be  found  in  inguinal  or  femoral  hernise. 
The  large  intestine  may  be  altered  in  position  by  a  misplaced  or  enlarged 
kidney. 

Colotomy. — Colotomy  may  be  performed  in  either  lumbar  region, 
especially  in  the  left,  to  establish  an  artificial  anus  when  there  is  obstruc- 
tion below. 

Lumbar  colotomy  (Amussat's  operation)  is  now  rarely  employed.  It 
is  preferably  done  on  the  left  side,  for  it  is  nearer  the  anus.  A  vertical 
line  12  mm.  Q  in.)  behind  the  centre  of  the  iliac  crest  represents  the  course 
of  the  colon.  This  line  crosses  the  guide  to  the  colon,  the  outer  border  of 
the  quadratus  lumborum.  (See  Lumbar  Region.)  The  line  of  the  ascend- 
ing colon  is  a  little  more  mesial  than  that  of  the  descending  colon.  The 
kidney  intervenes  between  the  colon  and  the  parietes  in  the  upper  part  of 
the  iliocostal  space.  In  the  lumbar  operation  the  colon  is  opened  retro- 
peritoneally  along  the  attached  area,  which,  in  the  empty  state,  varies 
from  20  to  25  mm.  (f  to  1  in.)  in  width,  and  in  the  distended  condition 
may  reach  5  cm.  (2  in.)  or  more  (Braune).  In  36  per  cent,  of  cases  the 
descending  colon  has  a  mesentery,  and  so  cannot  be  readily  reached 
extraperitoneally.  On  the  retroperitoneal  surface  neither  the  appendices 
epiploicse  nor  the  longitudinal  bands  aid  us  in  distinguishing  the  colon, 
for  the  latter  are  not  visible  and  the  former  are  not  present. 

In  the  newborn  the  ilio-costal  space  is  very  limited  and  entirely  occupied 
by  the  kidney,  so  that,  although  the  colon  is  then  altogether  outside  of 
the  kidney,  colotomy  is  done  in  the  inguinal  region. 

Inguinal  colotomy  (Littre's  operation)  is  the  one  most  often  practised  in 
adults  as  well  as  in  children.  The  oblique  incision  is  parallel  with  and  a 
short  distance  (3.5  cm.;  1J  in.)  from  the  outer  half  of  Poupart's  ligament, 
and  may  be  intermuscular.  The  opening  is  made  in  the  sigmoid  loop  pre- 
ferably at  its  lower  end,  for  the  loop  then  serves  as  a  fecal  reservoir,  the 
movements  are  more  formed,  and  there  is  much  less  danger  of  inconti- 
nence. If  the  artificial  anus  is  to  be  only  temporary,  a  transverse  spur  of 
mucous  membrane  is  made  opposite  the  lower  end  of  the  opening  to 
prevent  the  contents  passing  into  the  lower  segment  of  the  gut.  If  the 
opening  is  to  be  permanent,  the  distal  end  is  closed  and  dropped  back  and 
the  proximal  end  is  brought  out  through  the  wound  and  then  passed 
beneath  the  skin  (or  skin  and  fascia)  to  an  opening  below  the  outer  end 
of  Poupart's  ligament  and  sutured  there.  The  pad  of  a  truss,  applied 
over  the  2.5  to  5  cm.  (1  to  2  in.)  of  skin  beneath  which  the  gut  passes, 
will  control  all  passages  through  the  opening.    We  easily  distinguish  the 


THE  ABDOMINAL  VISCERA  359 

sigmoid  loop  from  the  coils  of  the  small  intestine,  which  often  present 
themselves,  by  the  bands,  sacculi,  and  appendages,  and  by  its  position. 

The  Liver.— The  liver  (Figs.  109, 121, 122,  and  126)  is  the  largest  gland 
in  the  body,  and  on  account  of  its  bulk,  as  well  as  its  position,  it  is  much 
exposed  to  injury.  In  size  it  averages  17.5  to  25  cm.  (7  to  10  in.)  from 
right  to  left,  7.5  to  15  cm.  (3  to  6  in.)  from  before  backward,  and  15  to 
17.5  cm.  (6  to  7  in.)  from  above  downward,  in  the  right  lobe.  It  is  larger 
in  men  than  in  women,  and,  pathologically,  it  is  subject  to  great  variations 
in  size  and  weight,  especially  to  enlargement.  At  birth  it  is  relatively 
much  larger  than  in  the  adult,  reaching  below  the  costal  margin  and  as  far 
to  the  left  as  the  spleen.  Owing  to  its  size  and  weight  in  the  infant,  a 
baby  is  not  laid  on  its  left  side  soon  after  feeding,  on  account  of  the  press- 
ure of  the  right  lobe  on  the  stomach.  It  is  not  until  the  sixth  or  eighth 
year  of  childhood  that  the  anterior  border  becomes  level  with  the  right 
costal  margin. 

Its  weight  is  between  50  and  60  ounces,  but  varies  according  to  its  size 
and  the  amount  of  blood  contained.  As  it  contains  nearly  half  a  kilo- 
gram of  blood,  it  weighs  much  more  during  life  than  at  postmortem.  At 
birth  it  is  one-twentieth  of  the  weight  of  the  body;  in  the  adult  male  one- 
fortieth.    Its  volume  is  about  95  cubic  inches. 

The  consistency  of  the  liver  is  firmer  than  that  of  other  glands,  but  it 
is  friable.  This  fact,  together  with  its  size,  fixity,  and  close  parietal  rela- 
tions, explains  why  it  is  more  often  ruptured  from  contusions  and  falls 
than  any  other  abdominal  viscus.  Ruptures  occur  most  commonly  near 
the  supporting  ligaments.  Free  hemorrhage,  often  fatal,  results  from 
such  an  injury  because  the  hepatic  veins  are  held  open  by  the  liver  sub- 
stance, to  which  their  walls  are  adherent,  there  are  no  valves  in  the  portal 
and  hepatic  veins,  and  the  latter  connect  directly  with  the  inferior  cava. 

The  liver  is  moulded  to  the  surrounding  organs  which  give  it  its  shape, 
that  of  an  ovoid  bevelled  off  on  its  under  part,  especially  at  the  left  end. 
When  examined  in  position  we  find  three  surfaces:  a  posterior,  resting 
against  the  upper  part  of  the  posterior  abdominal  wall,  here  formed  by 
the  diaphragm;  an  upper,  fitted  into  the  vault  of  the  diaphragm,  and  hence 
looking  forward  also  in  front;  and  an  inferior,  which  rests  upon  the 
abdominal  viscera  as  upon  a  pillow.  The  left  lobe,  large  at  birth,  dimin- 
ishes so  much  in  size  in  early  life  that  the  falciform  ligament,  which  repre- 
sents the  division  between  the  right  and  left  lobes  and  contains  the  round 
ligament  in  its  free  edge,  is  displaced  to  the  right  of  the  median  line. 
Hence  median  abdominal  incisions  pass  the  umbilicus  on  the  left  to 
avoid  incising  these  ligaments  in  regaining  the  median  line  above  the 
umbilicus. 

Position. -—The  liver  lies  in  the  right  hypochondriuin  and  (he  epigas- 
trium, and  extends  into  the  left  h  v|»oehondriiun  a  distance  varying  from 
3.5  or  5  cm.  (1$  or  2  in.)  beyond  the  left  margin  of  the  sternum  to  the  lefl 
mammary  line.    When  enlarged  it  extends  farther  to  the  left,  under  the 

bit  fa]  e  ijl,  ;md  in  front  of  the  stomach  and  the  spleen,  as  in  the  child. 
The  bulk  of  the  liver  and  the  entire  right  lobe  is  to  the  right  of  the  median 
line. 


360  *THE  ABDOMEN 

Throughout  its  extent  it  occupies  the  vault  of  the  diaphragm,  hence 
its  upper  limit  is  on  a  level  with  the  lower  end  of  the  mesosternum  in  the 
middle  line,  the  middle  of  the  fourth  intercostal  space  in  the  right  mam- 
mary line,  the  seventh  rib  at  the  right  side,  and  the  upper  end  of  the  fifth 
space  in  the  left  mammary  line.  Behind  it  becomes  superficial  below  the 
right  lung,  opposite  the  tenth  and  eleventh  thoracic  vertebrae  and  ribs, 
but  its  upper  limit,  covered  by  lung,  is  level  with  the  ninth  thoracic 
vertebra.  It  is  overlapped  above  by  the  thin  margin  of  the  lung,  below 
this  by  the  costophrenic  sinus.  Over  the  latter  area  pleurae  and  dia- 
phragm intervene  between  the  liver  and  the  chest  wall.  Hence  a  pene- 
trating wound  in  the  area  between  the  upper  extent  of  the  liver  and  the 
lower  limit  of  the  lung1  (see  Lungs,  p.  245),  or  the  line  of  absolute  liver 
dulness,  may  involve  the  pleura,  right  lung,  diaphragm,  peritoneum,  and 
liver,  penetrating  four  layers  of  pleura.  Or,  if  the  wound  be  a  little  lower, 
it  may  escape  the  lung  and  only  involve  the  two  layers  of  pleura  of  the 
costophrenic  sinus,  in  addition  to  the  diaphragm,  liver,  etc.  The  altera- 
tion in  position  of  the  liver,  according  to  the  position  of  the  body  or  the 
movements  of  respiration,  should  be  remembered  in  diagnosticating  the 
course  and  effects  of  a  wound  from  the  situation  of  the  external  wound.  In ' 
front  the  xiphoid  cartilage  and  the  costal  cartilages,  from  the  sixth  to  the 
ninth  inclusive,  and  on  the  right  side  the  ribs,  from  the  seventh  to  the 
eleventh  inclusive,  cover  the  convex  surface  of  the  liver,  the  diaphragm 
being  interposed. 

In  percussing  the  chest  from  above  downward  we  find  a  region  of 
relative  liver  dulness  where  the  liver  is  overlapped  by  lung.  This  dul- 
ness increases  as  we  pass  to  the  lower  border  of  the  lung,  where  we  reach 
the  line  of  absolute  liver  dulness.  This  is  at  the  sternoxiphoid  articula- 
tion in  the  median  line,  the  sixth  intercostal  space  in  the  right  mammary 
line,  the  seventh  rib  in  the  axillary  line,  and  the  lower  border  of  the  ninth 
rib  in  the  scapular  line.  The  line  of  relative  and  absolute  liver  dulness 
is  liable  to  variation  with  the  changes  in  position  of  the  diaphragm  in 
respiration;  in  diseases  affecting  the  extent  and  condition  of  the  lung; 
in  pleuritic  effusions;  in  abdominal  tumors,  ascites,  or  distention;  and 
in  variations  in  position  or  size  of  the  liver. 

The  lower  limit  of  the  normal  adult  liver  corresponds  to  that  of  its 
anterior  border  in  front.  In  the  median  line  it  is  at  a  point  midway 
between  the  sternoxiphoid  articulation  and  the  umbilicus;  in  the  mam- 
mary line  at,  or  12  mm.  (^  in.)  below,  the  costal  margin;  on  the  right 
side  it  follows  the  tenth  and  eleventh  ribs,  without  extending  beyond  the 
anterior  end  of  the  latter,  as  a  rule;  and  behind  it  reaches  the  level  of  the 
lower  end  of  the  eleventh  thoracic  vertebra.  This  would  represent  the 
lower  limit  of  the  liver  dulness  except  behind,  where  it  is  continuous 
with  the  dulness  of  the  lumbar  region.  If  on  the  right  side  one  can 
palpate  the  liver  below  the  tenth  and  eleventh  ribs  in  quiet  breathing, 
the  liver  is  enlarged  or  displaced  downward.    On  the  extreme  right  the 

1  In  the  fifth  or  sixth  intercostal  space  in  front,  the  sixth  at  the  side,  and  the  seventh,  eighth, 
or  ninth  behind. 


THE  ABDOMINAL  VISCERA  361 

lower  limit  of  the  liver  may  reach  the  level  of  the  second  lumbar  spine. 
In  the  subcostal  angle  the  liver  is  in  contact  with  the  anterior  abdominal 
walls,  and  its  lower  limit  is  represented  by  a  line  drawn  from  the  ninth 
right  to  the  eighth  left  costal  cartilage.  Here  one  can  palpate  the  lower 
or  anterior  margin  of  the  liver  when  the  abdominal  walls  are  thin. 

The  liver  is  quite  movable,  and  its  lower  limit  is  therefore  subject  to 
variation  from  physiological  and  pathological  causes.  Thus,  owing  to 
its  intimate  relations  with  the  diaphragm,  it  moves  upward  and  backward 
in  expiration,  downward  and  forward  in  inspiration,  so  that  with  a  deep 
inspiration  its  anterior  border  may  descend  below  the  costal  margin  in 
the  right  hypochondrium,  even  in  the  reclining  position.  In  the  supine 
position  the  edge  of  the  liver  is  12  mm.  (^  in.)  above  the  costal  margin  on 
the  right  side  in  front;  in  the  erect  position  it  descends  to  6  or  12  mm. 
(\  or  h  in.)  below  this  margin. 

We  have  already  noted  the  difference  in  position  in  children  up  to  the 
sixth  or  eighth  year.  In  women  the  liver  is  apt  to  reach  a  lower  level, 
owing  to  the  use  of  corsets,  and  in  those  who  lace  tightly  it  may  be 
pushed  down  even  to  the  iliac  fossa.  In  such  cases  of  "corset  liver"  the 
right  lobe  is  marked  by  a  deep  constricting  furrow,  due  to  the  pressure 
of  the  costal  margin.  In  this  furrow  the  transverse  colon  or  loops  of  the 
small  intestine  may  sometimes  be  found,  and  prevent  the  recognition  of 
the  continuity  of  the  lower  portion  with  the  liver,  by  percussion  or 
palpation.  Hence  it  has  been  mistaken  for  a  movable  kidney.  Among 
those  who  have  never  worn  tight  corsets,  as  well  as  among  those  who 
have,  a  long  tongue-shaped  process  may  project  downward  from  the 
right  lobe  near  the  gall-bladder.  This  is  known  as  "RiedePs  lobe," 
and  is  often  associated  with  cholelithiasis. 

In  uniform  enlargements  of  the  liver,  from  any  cause,  it  is  displaced 
downward,  where  we  can  diagnosticate  the  enlargement  by  percussion  and 
palpation.  Enlargements  of  the  liver  also  cause  a  bulging  of  the  right 
lower  ribs  and  costal  cartilages.  When,  however,  the  upper  part  of  the 
right  Lobe  is  involved  in  abscess  or  hydatids,  the  enlargement  and  the 
ana  of  dnlness  extend  upward,  raising  the  diaphragm  and  encroaching 
upon  the  right  lung.  In  emphysema,  pleurisy  with  effusion,  and  other 
conditions  associated  with  distention  of  the  right  side  of  the  thorax,  the 
lower  level  of  the  liver  is  lowered.  On  the  other  hand,  in  phthisis, 
collapse  or  retraction  of  the  lung,  and  diaphragmatic  hernia,  also  when  the 
liver  is  abnormally  small  and  in  conditions  involving  distention  of  the 
abdomen,  the  lower  level  of  the  liver  is  raised,  so  that  we  may  have 
tympanitic  resonance  over  the  costal  margin.  Jn  cases  of  suspected 
trie  or  intestinal  perforation  and  in  abdominal  injuries  absence  of 
liver  dnlness  in  front,  when  the  patienl  is  supine,  is  an  important  sign, 

indieating  the  presence  of  gas  between   the  liver  and    the   body   wall  in 
front,  of    it. 

Prom     the     above    we   obtain    the    limits    between    which    the    liver   is 

accessible  to  operation.     In  the  upper  pari  of  this  urea  the  liver  lies  deeply 

covered  by  the  lower  margin  of  the  lungs,  (■{<■.     AI>ove  the  lower  limit  of 
the  pleUIB  we  must  pass  through  the  latter  ami  the  diaphragm  to  reach 


362  THE  ABDOMEN 

the  liver.  This  is  necessary  when  the  trouble  affects  the  upper  part  of 
the  liver,  and  may  be  safely  done  by  suturing  the  diaphragm  into  the 
thoracic  opening  and  then  penetrating  the  diaphragm.  If  we  resect  the 
tenth  rib  in  the  right  axillary  line  we  find  the  diaphragm  with  no  inter- 
vening pleura,  but  on  penetrating  the  diaphragm  we  open  the  peritoneal 
cavity  and  disclose  the  lower  and  outer  portion  of  the  right  lobe  of  the 
liver. 

The  liver  is  held  in  position  by  the  attachment  of  the  hepatic  veins  to  the 
vena  cava  and  of  the  fibrous  tissue  near  the  vein  to  the  diaphragm,  by  its 
attachment  to  the  diaphragm,  within  the  area  embraced  by  the  coronary 
ligament,  by  the  latter  ligament,  by  intra-abdominal  pressure  exerted 
through  the  viscera  on  which  it  lies,  and  by  the  lateral  and  suspensory 
ligaments.  The  latter  ligament  is  of  little  or  no  service  in  suspension. 
Although  the  liver  is  firm  in  position  as  compared  with  other  intra- 
peritoneal organs,  yet,  as  we  have  seen,  it  is  also  subject  to  variation  in 
position.  From  the  relaxation  and  stretching  of  its  ligaments  and  of  the 
abdominal  walls,  especially  in  women  after  childbirth,  a  "dislocation"  of 
the  liver  or  a  "wandering  liver"  may  result.  A  more  moderate  downward 
displacement,  hepatoptosis,  is  not  uncommon,  and  several  have  been 
operated  on  successfully  by  hepatopexy.  Most  cases  have  general 
abdominal  ptosis  and  rarely  demand  operative  treatment.  With  its 
descent  a  forward  rotation  or  tilting  occurs,  so  that  its  diaphragmatic 
surface  comes  in  contact  with  the  abdominal  wall. 

According  to  Hasse  the  liver  is  stretched  in  inspiration  and  compressed 
in  expiration.  Doubtless  the  movements  of  respiration  stimulate  its 
circulation,  and  probably  on  this  account  it  is  placed  between  the  dia- 
phragm and  the  abdominal  walls.  Thus,  a  bon  vivant  or  one  of  active 
habits  suddenly  confined  to  bed,  by  a  broken  limb,  etc.,  becomes  bilious 
from  a  congestion  of  the  portal  circulation,  owing  to  the  little  stimulation 
it  receives  from  the  movements  of  respiration,  which  is  now  quiet. 

Relations. — The  diaphragm  above  separates  the  upper  surface  of  the 
liver  from  the  pleural  and  pericardial  cavities.  The  latter  corresponds  to  a 
flattened  area  on  the  upper  surface  of  the  left  lobe.  The  close  relations 
of  the  liver  with  the  pleura,  lungs,  and  heart  explains  how  hydatid  cyst  or 
abscess  of  the  liver  may  burst  into  the  pleura  or  lung,  or  even  into  the 
pericardium.  Thus  it  happens  that  pieces  of  liver,  disintegrated,  it  is 
true,  may  literally  be  coughed  up.  Similarly  empyema  has  been  known 
to  penetrate  the  diaphragm  and  give  rise  to  a  subdiaphragmatic  or  an 
hepatic  abscess.  The  liver  may  also  be  damaged  when  the  right  lower 
ribs  are  fractured,  owing  to  their  close  relations.  The  broken  ends  of 
the  ribs  have,  in  some  cases,  been  driven  into  the  liver  through  the 
diaphragm.  If  the  smooth  upper  surface  of  the  liver  is  roughened  by 
inflammation  its  movements  in  respiration  give  rise  to  a  friction  sound 
similar  to  that  in  pleurisy. 

The  posterior  surface  of  the  liver  rests  upon  the  right  suprarenal  body, 
to  the  left  of  this  it  is  grooved  for  the  vena  cava,  and  farther  to  the  left  it 
lies  upon  the  crura  of  the  diaphragm,  with  the  various  vessels  and  nerves 
between  or  within  them,  and  the  esophagus.    In  case  of  great  enlargement 


THE  ABDOMINAL  VISCERA  363 

of  the„liver  these  structures  may  suffer  a  certain  degree  of  compression. 
The  possibility  must  be  admitted  of  a  rupture  of  the  liver  without  tearing 
the  peritoneal  coat.  Such  injuries  are  not  likely  to  be  fatal.  They  may 
reach  the  surface  of  the  organ  behind,  on  the  fairly  extensive  non-peri- 
toneal surface.  Here  also  a  wound  may  occur  or  an  incision  be  made  into 
the  liver  without  opening  the  peritoneal  cavity,  but,  owing  to  its  position, 
only  after  passing  through  the  pleural  cavity. 

The  under  surface  of  the  right  lobe  is  in  contact  with  the  upper  half 
or  two-thirds  of  the  right  kidney  and  the  suprarenal  capsule,  to  the  left 
of  this  with  the  duodenum  (first  and  second  parts),  and  in  front  of  these 
with  the  colon.  To  the  left  of  the  neck  of  the  gall-bladder  lies  the  pyloric 
end  of  the  stomach  in  relation  with  the  quadrate  lobe.  The  lower  surface 
of  the  left  lobe  projects  as  the  tuber  omentale,  which  rests  upon  the  lesser 
omentum,  and  in  front  of  and  to  the  left  of  this  it  is  concave,  where  it 
covers  the  lesser  curvature,  cardia,  and  part  of  the  anterior  surface  of  the 
stomach,  to  an  extent  varying  inversely  with  the  fulness  of  that  organ. 
It  may  even  cover  the  fundus  of  an  empty  contracted  stomach. 

From  these  relations  we  see  that  an  abscess  of  the  liver,  after  inflam- 
matory adhesion,  may  open  inferiorly  into  the  colon,  duodenum,  stomach, 
or  right  kidney,  and  also  that  an  abscess  of  or  about  the  right  kidney  may 
extend  to  the  liver.  More  than  half  of  the  liver  abscesses  that  rupture 
do  so  in  an  upward  direction.  Abscess  of  the  liver  is  usually  the  result 
of  infection  of  the  portal  vein  through  some  of  its  radicles.  When  this 
infection  is  from  a  septic  process,  most  often  an  appendicitis,  there  are 
usually  multiple  embolic  abscesses,  which  follow  a  suppurative  pyle- 
phlebitis. Occasionally  w^ith  pyogenic  infection  there  is  a  single  localized 
abscess,  or  a  group  of  several  which  fuse  into  one.  The  common  form  of 
localized  abscess  is  due  to  infection  by  amebse  coli  from  amebic  dysentery. 
This  form  is  known  as  "tropical  abscess,"  owing  to  its  common  occur- 
rence, and  that  of  its  cause,  in  the  tropics.  Abscess  of  the  liver  may  also 
follow  surgical  operations  upon  the  same  parts.  The  secondary  or 
metastatic  abscesses  of  pyemia  are  frequently  found  in  the  liver,  and, 
according  to  Bryant,  more  often  after  injuries  to  the  head  than  after  other 
injuries.  Tillaux  states  that  metastatic  abscesses  are  superficial,  other 
abscesses  deeper. 

We  have  already  seen  some  of  die  positions  in  which  hepatic  abscesses 
may  perforate;  in  addition,  then-  may  be  mentioned  die  peritoneal 
cavity  and  the  surface  of  the  body,  after  adhesion  of  (he  liver  to  the  body 
walls.    Jf  the  absces    is  pointing  in  the  latter  position,  it.  is  preferably 

opened    below    the    COSta]    margin    when    it    is    accessible    there. 

Hydatid  C1f8U  OCCUr  more  often   in   the  liver  than  in  all  other  viscera 

taken  together,  for  the  embryos  of  the  eggs  of  Tenia  echinococcus  readily 

penetrate  the  \.    .1    of  the  walls  of  the  stomach  and  intestines,  and  are 

ukelj  to  enter  ;i  tributary  of  the  portal  system  and  be  carried  to  the  liver. 

discharge  themselves  in  the  same  directions  as  hepatic 

Coverings  and  Structure.    -The  liver  is  covered   by  peritoneum  except 
<r  the.  areas  between  the  layers  of   peritoneum   which  constitute 


364  THE  ABDOMEN 

the  ligaments  by  which  it  is  held  in  position;  (2)  along  the  transverse 
fissure,  where  the  lesser  omentum  is  attached  and  the  vessels  and  ducts 
enter  or  emerge;  and  (3)  at  the  bottom  of  the  fissure  for  the  gall-bladder, 
where  the  latter  intervenes  between  the  liver  and  peritoneum.  Hence 
most  operations,  wounds  or  affections  of  the  liver,  which  reach  the  surface, 
must  involve  the  peritoneum. 

Beneath  the  peritoneal  coat,  or  in  place  of  it  where  it  is  wanting,  is 
a  thin  coat  of  fibrous  tissue,  which  at  the  transverse  fissure  accompanies 
and  loosely  invests  the  vessels  and  ducts  throughout  the  liver.  This 
fibrous  tissue,  Glisson's  capsule,  forms  a  lattice-work  throughout  the  liver, 
which  is  thereby  divided  up  into  minute  lobules,  1  to  2  mm.  in  diameter. 
This  fibrous  lattice- work  may  become  swollen  in  cirrhosis  or  in  hepatitis. 
In  the  latter  the  swelling  is  the  result  of  acute  inflammation,  and  the  liver 
is  enlarged  and  tender.  In  cirrhosis  the  swelling  is  usually  due  to  chronic 
alcoholic  irritation,  which,  if  continued,  results  in  hypertrophy  of  the 
fibrous  tissue.  This  produces  a  large,  hard  liver,  the  first  stage  of  cir- 
rhosis. The  swelling  or  hypertrophy,  obstructing  the  flow  of  bile  from  the 
lobules,  causes  a  certain  degree  of  jaundice,  from  the  absorption  of  the 
coloring  matter,  and  dyspepsia  is  a  constant  symptom  from  portal  con- 
gestion. The  subsequent  contraction  of  the  new  fibrous  tissue  renders 
the  liver  hard,  fibrous,  and  often  smaller  than  normal,  and  compresses  the 
branches  of  the  portal  vein.  This  causes  great  congestion  of  the  parts 
which  feed  the  portal  vein,  i.  e.,  the  stomach,  intestines,  pancreas,  and 
spleen,  with  enlargement  of  the  latter  two.  This  results  in  varicose  veins 
of  these  parts,  from  which  serous  exudations  (ascites)  and  hemorrhages 
may  occur,  and  aggravates  the  functional  disturbance  of  the  digestive 
tract.  According  to  some  the  concurrent  toxemia  is  also  an  important 
factor  in  producing  ascites.  The  surface  of  the  liver  becomes  rough  and 
irregular  (hobnail  liver),  owing  to  the  contraction  of  the  fibrous  lattice- 
work which  reaches  the  surface. 

The  liver  may  be  greatly  and  uniformly  enlarged,  even  so  as  to  reach 
the  umbilicus,  in  certain  diseases  of  the  heart  and  lungs  where  the  flow 
of  blood  from  the  hepatic  veins  into  the  vena  cava  is  impeded,  owing  to 
the  congestion  of  the  right  heart.  Fatty  degeneration  is  another  condition 
which  may  cause  an  enlargement  of  the  liver,  sometimes  of  enormous 
size. 

Vessels  and  Nerves. — These,  invested  by  Glisson's  capsule,  enter  the 
liver  at  the  transverse  fissure,  which  they  reach  by  ascending  between  the 
two  layers  of  the  small  omentum  near  its  right  margin  and  in  front  of  the 
foramen  of  Winslow. 

The  hepatic  artery  supplies  largely  the  duct  and  vessel  walls  and  the 
fibrous  tissue. of  the  liver.  Brewer  has  called  attention  to  the  frequency 
of  anomalies  in  the  position  and  branching  of  this  vessel,  which,  how- 
ever, are  seldom  of  surgical  importance.  The  portal  vein  brings  by  far 
the  greater  part  of  the  blood  to  the  liver  and  practically  all  that  which 
reaches  the  liver  cells.  It  comes  from  all  the  organs  concerned  in  diges- 
tion and  absorption.  As  the  right  primary  branch  of  the  vein  is  larger 
and  a  direct  continuation  of  the  main  vein,  embolic  material  carried  to  the 


THE  ABDOMINAL  VISCERA 


365 


liver  commonly  involves  the  right  lobe.  The  results  of  obstruction  of 
the  portal  vein  are  seen  in  enlargement,  congestion,  varicosities,  hemor- 
rhage, serous  exudation  within  (diarrhea)  and  without  (ascites),  and 
impairment  of  the  function  of  the  viscera  containing  the  sources  of  the 
vein  (Fig.  120). 

In  such  cases  the  anastomotic  circulation  of  the  portal  system  comes  into 
play,  viz.,  certain  of  the  superficial  branches  on  the  liver  with  the  phrenic 
veins;  the  veins  of  the  round  ligament  with  the  epigastric  veins; 
the  hemorrhoidal  veins  with  branches  of  the  internal  iliac;  the  gastric 
with  the  esophageal  veins;  and  small  branches  on  the  pancreas  and 
on  the  parts  of  the  intestine  destitute  of  a  mesentery  with  the  veins  of 
the  parietes  and  viscera  (kidneys),  with  which  they  are  in  contact. 
Operations  are  now  done  to  increase  this  compensatory  circulation  by 
producing  adhesions  between  the  omentum  and  parietal  peritoneum  by 


Fig.  120 


LIVER 


DYSPEPSIA 

MORNING  VOMITING 

HEMATEMESIS 


PALLOR 
PAIN 
ENLARGEMENT 


HEMORRHOIDS 


I)i;ii{i-:iiii  showing  anatomical  relations  of  certain  clinical  phenomena  in  cirrhosis  of  the  liver. 

(Hare  and  Taylor.) 


suture  (Talma's  operation)  or  between  the  omentum  and  the  subcutane- 
ous tissue  of  the  abdominal  wall  (Narath's  operation).     In  the  former 
operation  attempts  are  also  made  to  effect  adhesions  between  the  liver 
and  spleen  and  the  diaphragmatic  peritoneum. 
Lymphatics.    The  Lymphatics  of  the  liver,  both  superficial  and  deep, 

terminate    ID    several    groups   of    nodes;    (1)  The    nodes   of    the   hilum, 
Usually  iii  two  hepatic  eh  a  ins  along  the  hepatic  artery  and  the  bile  duets; 

form  the  most  important  group  and  nexl  to  them.     (2)  Mediastinal 
a   around  the  inferior  cava  and  (b)  behind  the  xiphoid.    (3)  Peri- 
esophageal nodes  continuous  with  the  coronary  nodes  of  the  stomach. 
I    The  node    around  the  celiac  axis.    (  hie  or  more  of  these  groups  of 
nodes  may  be  involved  in  hepatic  cancer. 

The  nerves  are  from  the  left  vttgueaad  the  celiac  pleocus  (sympathetic). 
The  former  filaments,  fewer  in  number,  pass  from  the  lesser  curvature 


366  THE  ABDOMEN    • 

of  the  stomach  between  the  folds  of  the  small  omentum.  The  pain  over 
the  right  shoulder  in  liver  disease,  such  as  hepatitis,  etc.,  is  a  reflex  in  the 
supra-acromial  nerve  due  to  the  fact  that  it  is  a  branch  of  the  fourth 
cervical  nerve,  which  also  helps  to  form  the  phrenic  nerve,  filaments 
of  which  enter  the  liver  from  the  diaphragm.  This  reflex  pain  is  com- 
monly on  the  right  side,  for  the  right  lobe  is  usually  chiefly  involved.  The 
most  sensitive  part  of  the  liver  is  that  about  the  neck  of  the  gall-bladder 
and  the  common  bile  duct,  which  receive  filaments  from  the  last  two 
thoracic  and  first  lumbar  nerves,  which  also  pass  onto  the  diaphragm. 
This  explains  the  diaphragmatic  spasm  of  gallstone  colic  and  the  occa- 
sional disturbance  of  diaphragmatic  respiration  in  operations  in  this 
region  (Mayo). 

Carcinoma  of  the  liver  is  a  common  condition,  not  as  a  primary  but  as 
a  secondary  or  metastatic  growth,  usually  from  the  stomach,  intestines, 
uterus,  or  mammae.  These  growths  are,  as  a  rule,  multiple  and  diffuse. 
When  not  diffuse  a  tumor  of  some  size  may  be  removed,  for  a  consider- 
able part  of  the  liver  may  be  removed  without  disturbance  of  function. 
Experimentally  three-fourths  have  been  safely  removed  in  animals. 
The  part  remaining  hypertrophies,  and  probably  the  liver  may  be  regen- 
erated. In  such  cases  the  escape  of  bile  is  not  usual,  nor  is  it  necessarily 
fatal.  Hemorrhage  can  be  controlled  by  the  cautery,  where  the  vessels 
are  not  large,  or  by  the  clamp,  by  crushing  or  by  suture  of  the  wound  or  of 
vessels,  where  there  are  larger  vessels  which,  as  we  have  seen,  are  held 
open  by  their  connection  with  the  tissues  in  which  they  lie.  As  the 
blood  pressure  within  the  liver  is  very  low,  slight  pressure  also  checks 
hemorrhage. 

Anomalies  are  not  common  in  the  liver.  The  left  lobe  may  be  unusually 
small  or  large,  or  a  portion  of  it  may  be  connected  with  the  rest  by  a 
pedicle  of  peritoneum  containing  only  bloodvessels,  and  so  a  movable 
kidney  or  an  abdominal  tumor  may  be  simulated.  The  liver  is  found 
on  the  left  side  in  transposition  of  the  viscera. 

The  Gall-bladder.— The  pear-shaped  gall-bladder  (Figs.  109,  110, 
121  and  122)  is  6.5  to  10  cm.  (2^  to  4  in.)  long  by  4  cm.  (1|  in.)  wide 
at  the  fundus,  and  will  contain  about  30  gm.  (1  oz.).  Its  walls  are 
very  elastic,  and  hence  may  become  greatly  distended  from  the  obstruc- 
tion of  the  cystic  duct  and  some  forms  of  obstruction  of  the  common 
duct,  so  as  to  contain  a  pint  and  more  and  extend  even  below  the 
umbilicus.  It  is  so  lodged  in  the  cystic  fossa  between  the  right  and 
quadrate  lobes  of  the  liver  that  its  larger  end,  or  fundus,  projects 
forward,  downward,  and  to  the  right,  beyond  the  notched  anterior 
margin  of  the  liver,  so  as  to  lie  behind  the  abdominal  wall  just  below 
the  edge  of  the  ninth  right  costal  cartilage  and  just  lateral  to  the  right 
rectus  muscle.  When  distended  it  is  usually  protruded  downward  in 
a  line  passing  somewhat  to  the  right  of  the  umbilicus.  The  fundus  lies 
below  the  level  of  the  neck  in  the  upright  posture,  but  drains  back  to  it  in 
the  supine  position.  When  enlarged  it  can  be  percussed  but  better  pal- 
pated external  to  the  rectus  muscle.  Such  a  tumor  moves  with  respira- 
tion, for  it  is  connected  with  the  liver.    It  is  often  contracted  and  smaller 


PLATE  XXXIV 


FIG.   121 


Portal  nefe-pn 
Hepatic  dacM^H 
tie  rlttrt    \'''JS 
Bepatic  artery — r|S 


ltigtU  Suprarenal, 
capsule 

Pyloric  orifice 
Right  gtutro-epiploic 

artery 


Superior  mesenteric 
vein 


Spermatic  vessels 


8pt  rmatie  vessels 
Inferior  mcucntcrir  artery 


Viscera  of  the  Upper  Part  of  the  Abdomen.  The  liver  is  lifted 
up,  showing  the  gall-bladder  and  the  upper  part  of  the  gall 
ducts.     (Testut.j 


THE  ABDOMINAL  VISCERA 


367 


than  normal,  especially  in  cases  of  long-standing  inflammation,  when  it 
may  become  almost  obliterated. 

When  normal  the  gall-bladder  cannot  be  palpated  through  the  abdomi- 
nal wall.  It  may  lie  entirely  under  cover  of  the  liver,  whose  anterior 
border  is  usually  notched  (the  cystic  notch)  over  the  fundus  of  the  gall- 
bladder. Its  narrow  end  or  neck  extends  backward,  upward,  and  to  the 
left  toward  the  transverse  fissure,  where,  curving  first  to  the  right  and 
then  to  the  left  in  an  S-shaped  manner,  the  cystic  duct  leads  off  from 
its  upper  part  and  continues  its  spiral  course. 

Fig.  122 


Relation!  <>f  the  gall  bladder  and  bile  duot.     (Mayo.) 


It  is  held  in  position  by  the  attachment  to  the  liver  of  its  upper  one- 
eighth  to  one-third  by  areolar  tissue  and  of  its  under  surface  and  sides 
by  peritoneum  reflected  from  the  liver.  Occasionally  the  peritoneum 
completely  surrounds  the  gall-bladder,  forming  a  short  mesentery  which 
luspends  it  from  the  under  surface  of  the  liver.  More  commonly  only 
tli<-  posterior  half  or  bo  of  the  organ  is  provided  with  a  mesentery.    At 


368  THE  ABDOMEN 

times  an  extension  outward  of  the  free  border  of  the  small  omentum  to 
the  lower  surface,  even  as  far  as  the  fundus,  forms  a  posterior  mesentery 
(Brewer).  Also  a  peritoneal  fold  occasionally  connects  the  body  of  the 
gall-bladder  with  the  anterior  aspect  of  the  transverse  colon.  Normally 
the  gall-bladder  can  be  readily  stripped  by  blunt  dissection  from  the 
under  surface  of  the  liver  after  its  peritoneal  attachments  are  divided. 

The  upper  surface  is  in  relation  with  the  liver,  the  wider  surface  is  in 
contact  with  the  transverse  colon  in  front,  and  with  the  bend  between  the 
first  and  second  portions  of  the  duodenum,  and  oftentimes  with  the  pyloric 
end  of  the  stomach,  behind,  near  the  neck.  These  parts  are  found  stained 
with  bile  after  death,  and  into  these  parts  gallstones  may  pass  from  the 
gall-bladder  after  adhesion  and  ulceration.  A  fistulous  tract  from  the 
gall-bladder  most  often  opens  on  the  surface  of  the  abdominal  wall  and 
allows  the  escape  of  gallstones  and  fluid  contents. 

Beneath  the  partial  peritoneal  covering  the  wall  is  made  up  of  fibrous 
tissue  with  some  muscular  fibers,  principally  longitudinal,  and  it  is  lined 
with  mucous  membrane.  The  viscid  secretion  of  the  latter  mingles  with 
the  bile,  hence  the  bladder  is  more  than  a  reservoir.  Its  secretion  is 
often  the  principal  content  of  the  distended  bladder  (hydrops  of  the  gall- 
bladder), as  when  the  cystic  duct  is  obstructed.  If  its  contents  are  puru- 
lent, we  call  the  condition  empyema  of  the  gall-bladder.  In  several 
reported  cases  the  gall-bladder  has  served  as  a  reservoir  for  typhoid 
bacilli,  from  which  the  infection  has  been  scattered  with  the  stools. 
The  function  of  the  gall-bladder  is  probably  unimportant.  Its  capacity 
of  one  ounce  is  trifling  in  comparison  with  the  twenty-four-hour  output  of 
20  to  30  ounces  or  more  of  bile.  It  has  also  not  been  proved  that  the 
gall-bladder  contracts  forcibly  when  full.  It  may  produce  a  steady 
instead  of  an  intermittent  flow  into  the  duodenum  (Murphy).  Absence 
of  the  gall-bladder,  congenitally  or  by  reason  of  inflammation  or  removal, 
causes  no  disturbance  of  function. 

The  bile  is  not  sterile,  but  contains  a  few  attenuated  bacteria  that 
have  survived  their  passage  through  the  liver.  This  and  interference 
with  drainage  of  the  gall-bladder  probably  underlies  gallstone  disease 
(Lartigau). 

Gallstones  are  frequently  present  in  the  gall-bladder,  often  without 
giving  any  sign  of  their  presence  during  life  and  only  discovered  at 
autopsy.  They  are  formed  mainly  of  cholesterine,  and  vary  from  a 
flaxseed  to  a  hen's  egg  in  size.  The  smaller  ones  may  pass  through 
the  ducts  into  the  intestine;  the  larger  ones,  if  passed,  enter  the  bowel 
through  a  fistulous  opening.  It  is  impossible  to  feel  gallstones  through 
the  abdominal  wall;  in  fact,  even  through  the  open  abdomen  one 
cannot  surely  say  whether  a  distended  gall-bladder  has  stones  in  it  or 
not.  Though  often  innocuous,  they  may  provoke  inflammation  of  the 
gall-bladder  (cholecystitis)  and  various  obstructive  conditions  of  the 
bile  passages.  Cholecystitis  is  due  to  an  infection  by  colon,  typhoid, 
or  pyogenic  bacteria  which  reach  the  gall-bladder  through  the  bile 
ducts,  blood,  or  lymphatics.  It  may  be  the  seat  of  a  primary 
malignant  growth, 


THE  ABDOMINAL  VISCERA  369 

The  opening  of  the  gall-bladder,  done  on  account  of  empyema,  dis- 
tention, inflammation,  gallstones,  etc.,  is  called  cholecystotomy.  Chole- 
cystectomy is  the  removal  of  the  gall-bladder,  which  is  done  on  account 
of  a  tumor,  gangrene,  or  inflammation  with  obliterated  cystic  duct  and 
thickened,  contracted  bladder  walls,  etc.  When  an  obstruction  of  the 
common  bile  duct  cannot  be  removed  we  may  open  the  distended  gall- 
bladder and  connect  it  with  the  jejunum,  duodenum  or  transverse  colon 
(cholecystenterostomy),  so  that  the  bile  has  a  new  route  to  the  bowel. 
Nature  sometimes  performs  the  same  operation  by  ulceration  after 
adhesion. 

Rupture  of  the  gall-bladder  as  well  as  of  the  bile  ducts  may  occur 
with  or  without  rupture  of  the  liver.  It  usually  takes  place  close  to  the 
neck,  and  is  more  likely  to  occur  when  the  liver  is  enlarged  and  the  gall- 
Madder  distended.  It  is  not  necessarily  fatal  if  the  bile  is  normal,  for 
then  it  is  poor  in  bacteria  and  only  excites  a  plastic,  adhesive  peritonitis 
which  walls  off  the  fluid.  It  only  excites  septic  peritonitis  when  sup- 
purative processes  have  preexisted  in  the  gall-bladder. 

The  lymphatics  of  the  gall-bladder  pass  to  a  chain  of  nodes  which  is  a 
satellite  of  the  cystic  and  common  ducts.  One  is  generally  found  at  the 
junction  of  these  two  ducts.  In  inflammatory  conditions  they  may 
become  so  enlarged  as  to  cause  obstruction  by  pressure,  and  they  may  be 
mistaken  for  a  stone  in  the  common  duct. 

The  cystic  artery  which  supplies  the  gall-bladder  usually  branches 
off  from  the  hepatic  some  distance  posterior  to  the  cystic  duct  and 
reaches  the  gall-bladder  just  above  its  neck.  In  the  occasional  cases 
when-  it  is  a  branch  of  the  superior  pancreaticoduodenal  artery  it  runs 
along  the  common  duct  and  is  liable  to  be  injured  in  operations  upon 
thai  duet.  A  transverse  vein  in  front  of  the  supraduodenal  portion  of 
this  duet  may  also  be  injured  in  operations  upon  it. 

The  cystic*duct  ( Figs. 'l  10,  121,  and  123),  25  to  38  mm.  (1  to  \\  in.) 
long  (2.5  to  7.o  em.,  Joessel)  by  3  mm.  in  diameter,  runs  in  the  lesser 
omentum  from  right  to  left,  and  somewhat  backward  and  downward 
to  conned  the  neck  of  the  gall-bladder  with  the  hepatic  duct,  which 
it   joins  at    an   acute  angle   to    form    the   common    bile  duct. 

The  spiral  curve  of  the  neck  of  the  gall-bladder  and  of  the  adjoining 

part   of  the  cystic  duct   corresponds  to  the   irrcij ular  folds-  of  its  lining 

mucous  membrane,  which  sometimes  simulates  a  spiral  valve.  The 
effect  of  this  arrangement  is  to  make  it  almost  impossible  to  pass  a  probe 
along  this  duct,  unless  it  has  previously  been  distended  l>\  the  passage  of 
b  tour.  As  it  is  the  smallest  pur/  of  the  biliary  channel,  small  stones  that 
pa      it  easily  can   usually  quickly   pass  the  common  bile  duct.    It  is 

remarkable  what   large  stones  pass  the  cystic  and  common  ducts.     The 

tic  duct  may  be  greatly  enlarged  by  the  passage  of  a  stone  or  by  dis- 
tention in  chronic  cases  of  obstruction  in  the  common  duct.     Bile  only 

into  the  gall-bladder  when  its  How  into  the  duodenum  is  slopped. 
Obstruction   of    the   cystic   duel    i;    not    followed    by    jaundice,    for   the 

flow  of  bile  into  the  intestine  i-  not  checked,  and  though  the  gall-bladder 
may  be di  tended  it  i^  due  to  ii ,  nun  jecretion. 

j  i 


370 


THE  ABDOMEN 


The  right  and  left  bile  ducts  usually  join  one  another  at  an  obtuse 
angle  near  the  right  end  of  the  transverse  fissure,  shortly  after  their  exit 
from  the  liver,  to  form  the  hepatic  duct,  2.5  to  5  cm.  (1  to  2  in.)  long  and 

5  mm.  (^  in.)  in  diameter.  The  latter  is  directed  downward  and  a  little 
to  the  left  in  the  right  margin  of  the  small  omentum. 

The  common  bile  duct  averages  7.5  to  8.5  cm.  (3  to  3^-  in.)  in  length  and 

6  mm.  {\  in.)  in  width.  Its  course  lies  nearly  in  the  long  axis  of  the  body 
and  continues  that  of  the  hepatic  duct.  The  first  or  supraduodenal 
portion,  about  2.5  cm.  (1  in.)  in  length,  extends  down  to  the  first  portion 
of  the  duodenum  in  the  right  margin  of  the  small  omentum  (hepato- 
duodenal ligament).     This  is  the  point  of  election  for  the  removal  of 


Fig.  123 
vena  cava   inferior 


COMMON 

isun 

IMPRES- 
SION 


View  of  the  abdominal  viscera  from  behind,  after  removal  of  the  spinal  column  and  the  whole 
of  the  posterior  wall  of  the  abdomen,  the  peritoneum  being  left.      (After  His'  model.) 

stones  from  the  duct.  The  portal  vein  is  behind  it  and  to  the  left,  the 
hepatic  artery  is  to  the  left,  but  neither  are  near  enough  to  make  them 
liable  to  injury  if  care  is  taken.  It  lies  in  front  of  the  foramen  of 
Winslow  and  with  one  finger  in  the  foramen  and  the  thumb  in  front 
this  portion  can  be  palpated,  but  an  enlarged  lymph  node  in  the  small 
omentum  should  not  be  mistaken  for  a  stone  in  the  duct.  The  second 
or  retroduodenal  portion,  nearly  2.5  cm.  (1  in.)  long,  passes  behind  the 
duodenum,  to  the  wall  of  which  it  may  be  closely  applied.  The  vena 
cava  lies  postero-internally,  the  portal  vein  internally.  The  third  or 
pancreatic  portion,  20  to  25  mm.  (f  to  1  in.)  in  length,  passes  between 
the  head  of  the  pancreas  and  the  postero-internal  aspect  of  the  second 


THE  ABDOMINAL  VISCERA 


371 


portion  of  the  duodenum.  In  some  cases  (75  per  cent.,  Bunger)  it  is 
enclosed  in  pancreatic  tissue,  so  that  in  swelling  of  the  latter  it  becomes 
compressed  and  obstructed,  while  in  cases  where  it  lies  in  a  groove  in  the 
pancreas  it  may  be  pushed  out  of  the  way  without  being  compressed.  It 
passes  obliquely  through  the  wall  of  the  duodenum  for  18  mm.  (f  in.), 
opening  into  the  latter  by  a  little  round  or  oval  orifice  at  the  end  of  a 
papilla  on  its  postero-internal  aspect,  about  8.5  cm.  (3f  in.)  from  the 
pylorus,  or  3.5  cm.  If  in.)  below  the  crescentic  fold  in  the  lumen  of  the 
hr^t  bend  of  the  duodenum.     (See  Duodenum.) 

The  pancreatic  duct  usually  joins  the  common  bile  duct  in  the  duod- 
enal wall,  and  below  their  junction  there  is  a  little  dilatation  beneath  the 
mucous  membrane,  the  ampulla  of  Vater. 


Fig.  124 


I,  S.-grnent  of  second  portion  of  duodenum,  internal  aspect;  2,  orifice  of  ampulla  of   Vater; 
3,  its  cavity,  with  its  upper  wall,  3',  and  its  lower  wall,  3";  5,  common  bile  duct;  6,  duct  of 
log;   7,  valvuhr-  connivent.^s  overlying  papilla. 

The  papilla  (Figs.  123  and  124)  contains  the  narrowest  part  of  the 
common  duel  I  to  2  mm.),  hence  stones  are  likely  to  be  arrested  just 
above  it  in  (lie  ampulla.  The  papilla  is  nearly  covered  by  the  first 
normal  transverse  valvulae  ennniventes.  Running  down  from  this  opening, 
;iinl  the  rounded  projection  due  to  the  ampulla,  is  m  small  longitudinal 
fold  of  mucous  membrane.  This  appearance  facilitates  identification  of 
the  papilla,  which  is  assisted  if  we  can  express  ;i  drop  of  bile  and  if 
we  know  jiHt  where  to  Look  for  it.  The  oblique  course  of  the  duct 
through  the  duodenal  wall  and  perhaps  the  valvular  folds  of  its 
mucous  membrane,  described  by  Toldt,  preveni  the  backward  flow  of 
iIh'  intestinal  content  i.  The  lower  end  of  the  common  duel  lies  upon 
the  vena  cava,  hence  caution  is  required  in  incising  the  walls  of  the 
ducts. 


372  THE  ABDOMEN- 

The  common  duct  may  be  exposed  at  its  lower  end  by  opening  the  sec- 
ond portion  of  the  duodenum,  in  which  it  may  be  felt  by  the  finger  as  a 
cord-like  channel,  along  the  postero-internal  aspect.  By  slitting  up  the 
duct,  as  it  lies  in  the  walls  of  the  gut,  for  12  mm.  (^  in.)  from  its  opening, 
we  can  remove  stones  impacted  in  its  lower  end,  as  McBurney  has  shown. 
Above  this  point  we  can  expose  the  duct  by  incising  the  peritoneum  on  the 
right  of  the  duodenum,  loosening  the  latter  posteriorly  and  drawing  it 
toward  the  median  line.  Still  higher  we  can  expose  the  duct  by  dissect- 
ing up  the  distal  inch  of  the  first  portion  of  the  duodenum  from  its  pos- 
terior attachment  and  drawing  it  downward  and  inward.  We  may 
oftentimes  force  a  stone  along  the  duct  into  the  supraduodenal  portion 
from  a  lower  point,  incise  the  duct  (choledochotomy) ,  remove  the  stone, 
and  then  suture  the  duct  or  drain  it. 

All  the  operations  on  the  gall-bladder  and  ducts  are  performed  in  the 
so-called  subhepatic  space  (Morrison's  pouch),  bounded  by  the  right  lobe 
of  the  liver  above,  the  transverse  colon  and  mesocolon  below,  the  parietes 
down  to  the  iliac  crest  externally,  and  by  the  peritoneum  covering  the 
spine  internally.  The  duodenum  and  right  kidney  occupy  the  floor  of 
this  space,  and  the  pyloric  end  of  the  stomach  encroaches  upon  the  median 
side.  This  pouch  can  hold  nearly  a  pint  of  fluid  before  it  overflows  over 
the  pelvic  brim  or  through  the  foramen  of  Winslow.  It  can  be  well 
drained  through  a  lumbar  incision.  By  pushing  the  liver  up  and  retract- 
ing the  transverse  colon  down,  and  perhaps  pushing  the  stomach  to  the 
left,  we  get  room  for  exploration  and  operation,  though  all  the  biliary 
passages  lie  at  an  uncomfortable  depth.  This  may  be  partly  obviated  by 
placing  a  sandbag  or  firm  cushion  beneath  the  back  behind  the  liver,  and 
also  by  drawing  the  liver  downward  and  rotating  it  upward  and  outward 
so  as  to  turn  the  lower  surface  forward.  As  the  result  of  inflammatory 
adhesion  the  subhepatic  space  may  be  obliterated,  which  greatly  increases 
the  difficulties  of  operation. 

When  a  stone  becomes  impacted  in  one  of  the  ducts  the  muscle  fibers, 
which  are  mostly  circular  in  the  duct,  make  a  violent  spasmodic  effort 
to  dislodge  it.  This  may  be  partly  successful,  the  stone  may  pass  on  a 
little  ways  and  again  become  impacted,  and  so  on.  Thus  attacks  of 
hepatic  or  biliary  colic  succeed  one  another  until  the  stone  is  passed  or 
becomes  more  firmly  impacted.  A  stone  impacted  in  the  common  duct 
may  partly  or  wholly  stop  the  flow  of  bile  into  the  duodenum.  In  the 
latter  case  the  ducts  above  the  obstruction  become  distended,  the  stools 
become  clay-colored,  and  the  patient  jaundiced.  The  gall-bladder, 
curiously  enough,  is  rarely  distended,  but  is  contracted  in  nearly  90  per 
cent,  of  such  cases  of  chronic  common  duct  stone.  The  common  and 
hepatic  ducts  are  very  extensile,  so  that  they  become  much  distended  after 
obstruction  has  lasted  for  some  time.  Thus  in  most  such  cases  the 
finger  may  be  introduced  through  the  duct  up  to  the  junction  of  the  pri- 
mary divisions  and  down  to  the  obstruction.  Obstruction  may  also 
follow  pressure  from  without,  as  from  a  tumor  of  the  head  of  the  pan- 
creas. Stenosis  of  the  duct  may  also  be  due  to  inflammation  of  its 
mucosa. 


THE  ABDOMINAL  VISCERA  373 

Varieties. — The  gall-bladder  may  be  constricted  transversely  or 
longitudinally,  it  may  be  transposed,  within  the  substance  of  the  liver, 
or  even  absent,  in  which  case  the  hepatic  duct  is  usually  dilated  before 
opening  into  the  intestine.  The  common  duct  has  been  congenitally 
absent,  and  yet  life  was  possible  for  six  months  in  two  such  cases. 

The  Pancreas.— The  pancreas  (Figs.  109,  114,  121,  122,  and  123)  is 
a  retroperitoneal  organ,  and  lies  deeply  in  the  epigastric  and  left  hypo- 
chondriac regions,  behind  the  stomach  and  the  lesser  peritoneal  sac  and 
between  the  duodenum  on  the  right  and  the  spleen  on  the  left.  Hence  it 
is  not  easily  accessible  for  surgical  or  diagnostic  purposes.  It  crosses 
the  median  line  in  front  of  the  first  and  second  lumbar  vertebrae,  from 
6  to  12.5  cm.  (2+  to  5  in.)  above  the  umbilicus.  Although  it  has  been 
ruptured,  wounded,  or  even  herniated  (very  rarely,  in  some  cases  of 
diaphragmatic  hernia),  these  conditions  almost  never  affect  the  pancreas 
alone,  but  only  in  connection  with  similar  injuries  of  other  neighboring 
viscera.  It  may  sometimes  be  felt  on  deep  pressure  in  emaciated 
subjects  when   the  stomach  and  colon  are  empty. 

It  may  be  reached  by  raising  the  omentum  and  transverse  colon  and 
dividing  the  transverse  mesocolon,  or  by  dividing  the  gastrocolic  or  the 
gastrohepatic  ligaments,  and  then  the  peritoneum  at  the  back  of  the 
lesser  peritoneal  sac.  It  may  be  drained  posteriorly  by  an  incision  in 
the  left  costovertebral  angle. 

Although  it  has  relations  with  many  most  important  structures,  many 
of  these  relations  are  of  no  surgical  interest.  The  lower  end  of  the 
common  bile  duct  may  lie  in  a  groove,  more  often  (62.5  to  75  per  cent.) 
in  a  canal,  in  the  head  of  the  pancreas.  Hence  carcinoma  or  chronic 
inflammatory  enlargement  of  the  head  of  the  pancreas  may  so  press  upon 
the  duct  as  to  partly  or  completely  occlude  it  and  cause  persistent  jaun- 
dice. This  part  of  the  pancreas  has  the  vena  cava,  vena  porta?,  aorta, 
and  superior  mesenteric  vessels,  etc.,  behind  it,  so  that  removal  of  tumors, 
which  are  usually  situated  here,  is  almost  impracticable  unless  they  are 
encapsulated,  although  it  has  been  done.  The  pancreas  also  lies  in  front 
of  the  left  renal  vein  and  the  right  renal  vessels,  and  its  tail  is  in  front  of 
the  liilinn  and  the  middle  or  upper  part  of  the  left  kidney.  These  rela- 
tions  aii-  to  be  home  in  mind  in  nephrectomy. 

The  pylorus  of  the  full  stomach  lies  in  front  of  the  neck  of  the  pan- 
en;!-.  Tin-  splenic  vein  and  artery  lie  in  grooves  respectively  behind 
and  above  its  upper  bonier.  The  tail  of  the  pancreas  touches  the  spleen 
;ii  it-  lower  end  and  at  the  lower  part  of  the  gastric  surface.  From  the 
relations  of  the  pancreas  we  can  understand  the  pressure  symptoms  of 

pancreatic  tumor,  according  to  the  direction  of  its  growth  and  the  point 
of  origin.  In  operations  on  the  pylorus  or  the  spleen  it  is  important  not 
to  wound  the  pancreas  or  to  include  it  in  the  ligature.  Such  an  injury  to 
an  adherent  pancreas  in  pylorectoinv  for  pyloric  cancer  greatly  increases 
the  mortality.  Also  die  secretion  of  the  pancreas  may  perhaps  interfere 
with  the  healing  of  the  wound  by  dissolving  the  cicatrix  and  lead  to  an 

oh  tinate  fi  tula.  Perforating  ulcers  of  the  rear  wall. of  the  stomach  may 
re  ult  in  adhesion  of  the  hitter  to  the  pancreas, or, rarely,  in  abscess  of 


374 


THE  ABDOMEN 


the  pancreas.  A  biliary  calculus  lodged  just  beyond  the  ampulla  of 
Vater,  or  in  the  papilla,  obstructs  the  (pancreatic  duct,  which  usually 
joins  the  common  bile  duct  in  the  duodenal  wall  just  above  the  ampulla. 
Opie  has  shown  that  a  small  calculus  obstructing  the  outlet  of  the 
ampulla  converts  the  two  ducts  into  a  continuous  channel  permitting 
the  entrance  of  infectious  bile  into  the  pancreatic  duct  and  thus  causing 
acute  pancreatitis.  Chronic  pancreatitis  is  also  very  often  associated 
with  the  presence  of  gallstones.  The  occlusion  of  both  ducts  by  a  larger 
stone,  just  above  or  filling  the  ampulla,  affords  less  danger  to  the 
pancreas  on  account  of  the  accessory  duct  of  Santorini.    This  is  present 

Fig.  125 


GLAND  OF 
HEPATIC 
CHAIN 


HEPATIC 
ARTERY 


SUPERIOR 

MESENTERIC 

GLAND 


GLAND  OF 
COMMON 
BILE-DUCT 

GLAND  OF 
COMMON 
BILE-DUCT 

GASTRO- 

DUODENAL 
ARTERY 

RETRO- 
PANCREATIC 
GLAND 

PORTAL    VEIN 


RETRO- 
PANCREATIC 
GLAND 

RETRO- 
PANCREATIC 
GLAND 


Retropancreatic  lymph  nodes. 


in  all  cases  and  opens  into  the  duodenum  separately  2  cm.  (f  in.) 
above  the  papilla.  In  12  per  cent,  of  cases  it  is  the  main  outlet  of 
the  pancreas,  and  in  54  per  cent,  it  may  act  as  a  substitute  for  the 
duct  of  Wirsung,  if  the  outlet  of  that  is  closed,  by  communicating 
with  it  above.  The  entire  pancreatic  secretion  is  conveyed  by  the  duct 
of  Wirsung  in  83  per  cent,  of  cases.  Calculi  may  form  in  these  ducts  and 
give  rise  to  colic  resembling  gallstone  colic. 

Cysts  occasionally  occur  in  the  pancreas,  the  result  of  obstruction  of 
the  duct,  injury  or  other  causes.  Such  cysts  appear  in  the  epigastrium 
above  the  umbilicus,  usually  below  the  stomach,  which  is  pushed  up,  and 
above  the  transverse  colon.    In  other  cases  they  appear  above  the  stom- 


THE  ABDOMINAL  VISCERA 


375 


ach,  pushing  it  down,  while  occasionally  it  pushes  forward  between  the 
layers  of  the  transverse  mesocolon  or  bulges  the  latter  downward.  They 
require  opening  and  drainage  of  the  fluid,  which  may  be  under  great 
pressure.  Acute  inflammation  of  the  pancreas  (pancreatitis)  may  involve 
hemorrhage,  necrosis  or  abscess  of  the  pancreas,  fat  necrosis  or  general 
peritonitis,  and  demands  operation.  If  in  case  of  occlusion  of  the  pan- 
creatic duct,  acute  inflammation,  injury,  etc.,  the  fat-splitting  ferment 
of  the  pancreatic  juice  escapes  into  the  retroperitoneal  tissue  or  on  the 
surface  of  the  peritoneum,  it  causes  fat  necrosis.  Chronic  pancreatitis 
may  obstruct  the  common  bile  duct  by  pressure  and  also  calls  for  opera- 
tive treatment,  by  indirect  drainage  by  cholecystostomy.  In  not  a  few 
cases  accessory  pancreases  are  found  in  the  wall  of  the  stomach  or  small 


Fig.  126 


LOWER  LIMIT  OF  LUNG 

Outline  of  lower  half  of  bony  thorax,  showing  the  position  of  the  spleen,      (Merkcl.) 

intestine,  especially  the  duodenum,  and  may  be  mistaken  for  newgrowths. 
Several  cases  are  recorded  of  an  annular  growth  forming  a  ring  around  the 
second  part  of  the  duodenum,  which  it  may  constrict  so  as  to  cause 
dilatation  of  the  stomach  and  the  duodenum  above  it. 
The  Spleen.  -Position  (Figs.  !()'.),  12."),  L26,and  127).  -The spleen, the 
t  and  most  Important  of  the  ductless  glands,  Lies  in  the  dorsal  pari 
of  tin:  left  hypochondriac  and  epigastric  regions,  between  the  concavity 
of  the  diaphragm  behind  and  to  the  left,  the  fundus  of  the  stomach  in 
front  and  to  the  right,  the  left  kidney  and  the  splenic  flexure  of  the  colon 
internally  and  below.  Its  long  <ixis  corresponds  to  that  of  die  tenth  rib, 
and  it.  •••.tend,  between  tie'  eighth  and  eleventh  ribs.    The  upper  or 

l<irnrr  Ktul  extends  tO  within  3.5  to  .")  cm.  {\\  to  2  in. J  of  the  median  line, 


376 


THE  ABDOMEN 


or  within  2.5  cm.  (1  in.)  of  the  vertebral  column,  and  sometimes  touches 
the  latter.  It  is  on  a  level  with  the  tenth  thoracic  vertebra  or  the  ninth 
thoracic  spine.  Its  lower  end,  which  lies  farther  downward,  outward,  and 
forward  on  a  level  with  the  first  lumbar  spine,  nearly  reaches  the  mid- 
axillary  line,  but  normally  does  not  extend  beyond  the  left  costoclavicular 
line  (i.  e.,  from  the  left  sternoclavicular  joint  to  the  tip  of  the  left  eleventh 
rib). 

The  spleen,  therefore,  lies  under  cover  of  the  bony  thorax  and  cannot 
be  palpated  when  normal.  Its  position  is  affected  by  respiration,  though 
not  so  much  as  that  of  the  liver,  for  the  diaphragm  exercises  less  influ- 
ence upon  it.     It  sinks  somewhat  in  inspiration,  pleural  effusions,  and 

Fig.  127 


LOWER    LIMIT 
OF    LUNG 


LOWER    LIMIT 
OF    PLEURA 


EXT.  ARCUAT.  LIC. 

AND  LOWER  BORDER 

OF  DIAPHRAGM. 


EXT.  BORDER  OF 
ERECT.  SPIN.  M. 


EXT.  BORDER  OF 
QUAD.  LUMB.  M. 


Outline  of  the  abdominal  viscera  from  behind,  showing  their  relation  to   one  another,  the 

lower  ribs,  and  the  vertebrae:   ,  kidneys;  .spleen;  ,  liver; — , 

duodenal  loop  and  colon.      (Merkel.) 


emphysema;  it  rises  in  expiration,  and  is  pushed  up  by  ascites  and 
abdominal  tumors.  When  much  enlarged  it  displaces  the  heart  and  left 
lung  upward,  causing  palpitation  and  shortness  of  breath. 

The  spleen  is  held  in  position  by  peritoneal  folds  containing  some 
fibrous-tissue  strands.  The  lienorenal  or  lienophrenic  ligament  is  a 
double  fold  of  peritoneum  which  passes  from  the  abdominal  wall  at  the 
tail  of  the  pancreas  or  the  front  of  the  left  kidney  to  the  hilum  of  the 
spleen  and  encloses  the  splenic  vessels.  An  inconstant  fold,  belonging  to 
the  upper  end  of  this,  which  extends  from  the  left  crus  of  the  diaphragm, 
is  known  as  the  suspensory  ligament  of  the  spleen.  The  phrenocolic 
ligament  (sustentaculum  lienis),  passing  from  the  diaphragm,  opposite 
the  free  ends  of  the  tenth  and  eleventh  ribs,  to  the  splenic  flexure  of  the 


THE  ABDOMINAL  VISCERA  377 

colon,  forms  a  shelf  or  pocket  for  the  spleen,  especially  in  the  newborn, 
and  holds  it  up  by  supporting  the  colon  on  which  it  rests.  If  the  latter 
ligament  becomes  relaxed,  the  spleen  is  displaced  downward  and  lies 
more  vertically.  It  is  also  supported  by  intra-abdominal  pressure. 
Rarely  the  spleen  is  found  low  down  in  the  abdomen  or  even  in  the  pelvis. 
Such  a  "  wandering  spleen"  is  liable  to  atrophy  from  a  torsion  of  the 
vessels  in  the  lengthened  pedicle,  and  it  may  cause  so  much  pain  from 
stretching  of  the  vessels  and  nerves  as  to  require  removal. 

The  gastrospleuie  omentum  affords  but  little  fixation  to  the  spleen, 
more  to  the  fundus  of  the  empty  stomach.  When  the  stomach  is  empty 
this  omentum  lies  transversely,  while  the  full  stomach  separates  the 
two  layers  to  cover  its  distended  fundus.  Thus  the  full  stomach  comes 
in  direct  relation  with  the  spleen.  When  the  stomach  is  distended  the 
spleen  becomes  more  horizontal,  and  vice  versa. 

As  to  size,  the  spleen  varies  more  than  any  other  organ.  Its  normal 
average  in  the  adult  is  about  12.5  cm.  (5  in.)  in  length,  7.5  cm.  (3  in.) 
in  width,  and  3  cm.  (\\  in.)  in  thickness;  also  170  to  195  grams  in  weight 
in  the  cadaver,  and  about  one-sixth  more  when  filled  with  blood.  It  is 
relatively  large  in  childhood,  and  atrophies  in  old  age.  It  is  enlarged 
during  digestion,  in  cases  of  congestion  of  the  portal  vein,  in  malarial 
poisoning,  in  one  form  of  leukemia,  and  in  infectious  diseases.  It  may 
attain  such  size  as  to  reach  the  pelvis  and  nearly  fill  the  whole  abdomen, 
so  as  to  be  mistaken  for  an  ovarian  or  uterine  tumor,  but  unlike  tumors 
of  the  kidney  it  is  not  covered  in  front  by  intestines.  Its  weight  may 
equal  20  pounds  or  more.  In  the  child  the  enlarged  spleen,  in  its  earlier 
stages,  is  said  to  encroach  upon  the  thoracic  cavity  more  than  in  the 
adult,  owing  to  the  firmer  support  of  the  phrenocolic  ligament  in  the 
young.  More  rarely  the  spleen  is  enlarged  on  account  of  abscess,  cysts 
(especially  hydatids),  and  malignant  tumors.  In  cases  of  enlargement 
its  limits  may  be  determined  by  palpation  even  better  than  by  percussion. 
The  normal  notching  of  its  sharp  anterior  border  helps  to  identify  the 
spleen  when  enlarged  below  the  costal  margin.  Then"  are  not  infre- 
quently  supernumerary  spleens,  partly  or  entirely  detached  from  the 
mother  organ,  and  in  the  latter  ease  usually  situated  in  the  gastrosplenic 
or  gii.it  omentum,  or  in  the  transverse  mesocolon.  On  the  other  hand, 
tli^  spleen  may  be  congenitally  wanting. 

Owing  to  its  soft  consistence  it  is  very  friable,  and  therefore  liable  to 
rupture     But  this  accident   is  not  common  with   the  normal  spleen, 

owing  to  the  protection  afforded  by  its  position  and  relations  and  the 
fact  that  it  is  swung  up  by  and  rests  upon  elastic  peritoneal  folds.  When 
enlarged  (lie  spleen  is  more  readily  ruptured,  often  by  quite  insignificant 
violence  without  trace  of  injury  externally,  and  even  by  muscular  vio- 
lence, of  which  several  cases  are  recorded.  The  spleen  may  be  lacerated 
in  severe  fractures  of  the  left  ninth,  tenth,  or  eleventh  ribs,  by  the  broken 
end  of  a  rib  driven  through  the  diaphragm,  or  directly  l»v  the  violence 
which    produced  the  fracture.     Owing  to  the  extreme  Vascularity  of  the 

pleen  its  rupture  i-  often  fatal  from  hemorrhage  if  not  operated  upon. 

The   spontaneous    recovery    of   cases   of    limited    wounds    and    gunshot 


378  THE  ABDOMEN 

injuries  of  the  spleen  is  aided  by  the  contraction  of  the  muscle  fibers 
in  its  capsule,  which  narrows  the  opening  and  favors  the  arrest  of 
hemorrhage  by  coagulation  of  the  blood. 

Relations  (Figs.  114,  121,  and  123). — The  convex  dorsal  or  phrenic 
surface,  directed  backward,  upward,  and  to  the  left,  is  in  contact  with 
the  diaphragm.  It  is  separated  from  the  parietes  at  its  lower  end  by  the 
diaphragm,  higher  up  by  the  diaphragm  and  the  costophrenic  sinus  of 
the  pleura,  and  above  by  the  diaphragm  and  the  lower  edge  of  the  lung. 
These  relationships  explain  the  cases  where  wounds  of  the  spleen  are 
combined  with  those  of  the  lung  and  pleura  and  the  rare  cases  where 
abscess  of  the  spleen  has  perforated  through  the  diaphragm  into  the 
left  pleural  cavity.  The  concave  gastric  surface,  directed  forward  and 
inward,  is  in  contact  with  the  fundus  of  the  stomach  when  the  latter  is 
full,  but  not  when  it  is  empty  and  contracted.  The  tail  of  the  pancreas 
reaches  its  lower  end.  The  upper  end  and  the  upper  half  of  the  outer 
border  of  the  left  kidney  is  in  contact  with  the  renal  surface,  which 
looks  inward  and  downward.  At  the  lower  and  outer  end  of  the  spleen  is 
a  triangular  area  (basal  surface)  which  rests  upon  the  splenic  flexure  of 
the  colon  and  the  phrenocolic  ligament. 

These  relations  explain  the  difficulty  in  percussing  the  normal  or 
slightly  enlarged  spleen.  Its  upper  end,  above  the  tenth  rib,  is  over- 
lapped by  the  lung  and  covered  by  the  thick  muscles  of  the  back.  Below 
the  lung  it  rests  against  the  kidney  and  colon,  so  that  its  limit  cannot  be 
defined  by  percussion,  especially  if  the  colon  is  filled  with  fecal  masses. 
The  difficulty  is  still  further  increased  if  the  stomach  is  filled  with  food. 
The  lower  and  outer  end  is  the  only  part  determinable  by  percussion,  and 
even  here  fecal  masses  in  the  colon  may  interfere.  The  area  of  splenic 
dulness  may  disappear  in  emphysema  and  pleuritic  effusions;  and  it 
varies  in  respiration  as  well  as  with  any  change  in  position  or  size  of  the 
organ. 

The  spleen  is  entirely  covered  with  peritoneum  except  about  the  hilum, 
a  row  of  depressions,  on  the  gastric  surface  just  in  front  of  the  inner 
border,  where  the  vessels  enter  or  emerge  between  the  two  layers  of 
peritoneum  forming  the  gastrosplenic  omentum.  The  latter,  with  the 
contained  vessels,  forms  the  pedicle  which  requires  to  be  carefully  ligated 
in  extirpation  of  the  spleen  {splenectomy). 

Of  the  vessels,  the  tortuous  artery  is  very  large  for  the  size  of  the  spleen 
and  renders  it  a  very  vascular  organ.  It  also  sends  branches  to  the  pan- 
creas and  to  the  fundus  of  the  stomach  (vasa  brevia  in  the  gastrosplenic 
omentum).  The  splenic  vein  goes  to  form  the  portal  vein,  and  is  double 
the  size  of  the  artery.  It  lies  below  the  artery  and  runs  a  straighter  course. 
The  lymphatics  collect  in  nodes  at  the  tail  of  the  pancreas. 

Although  the  spleen  is  rich  in  bloodvessels,  it  is  poor  as  to  nerve  supply, 
which  comes  from  the  solar  plexus. 

Extirpation  of  the  spleen  {splenectomy)  is  indicated  and  has  been  done 
for  wounds  and  ruptures,  cysts  and  abscess,  simple  and  malarial  hyper- 
trophies, and  "wandering  spleen."  For  the  latter  condition  spleno- 
pexy has  also  been  advised  and  performed  by  stitching  the  spleen  in 


PLATE  XXXV 


FIG.   128 


Horizontal  Section  Passing  through  Hilum  of  the  Spleen, 
to  show  the  Relations  of  this  organ  to  the  peritoneum. 
(Schematic.) 


1.  Spleen. 

2.  Stomach. 

:',.  Tail  of  pancreas 

4.  Inferior  cava. 

.">.  Aorta. 

(>.  Splenic  artery. 

s.  Thoracic  abdominal  walls, 


9.   Gastrosplenic  omentum  containing 

vasa  brevia. 
1 1 .    Small  omenl  una. 
1 1'.  Its  free  righl  border. 
1  'J.    Foramen  of  Winslow  , 
13.     Leaser  peritoneal  sac. 
1  1.     Left   pleural  sinUS. 


THE  ABDOMINAL  VISCERA 


379 


place  and  forming  a  new  peritoneal  shelf  for  it.  In  splenectomy  a  free 
incision  is  made  along  the  left  costal  border,  or  sometimes  in  the 
median  line  or  in  the  left  semilunar  line.  The  most  important  and 
difficult  feature  is  securing  and  ligating  the  pedicle,  the  gastrosplenic 
omentum  and  lienorenal  ligament,  with  the  very  large  vessels  contained. 
If  too  much  traction  is  made  there  is  danger  of  tearing  these  vessels, 
especiallv  the  splenic  vein. 

The  Kidneys.— Position  (Figs.  109,  127,  129,  130,  and  131).— The 
kidneys  lie  retro  per  itoneally  and  are  deeply  placed,  one  on  either  side 
of  the  spine,  so  that  they  cannot  usually  be  palpated  when  normal  in 


Fig.  129 


OESOPHAGUS 


INT.    ARCUATE-i 
LIGAMENT 


ELEVENTH 
RIB 

HIATUS,  DIAPHRAG- 
MATICUS,  SHOW- 
ING   PLEURA 

EXTERNAL    ARCU- 
ATE    LIGAMENT 


TWELFTH  THORA- 
CIC   NERVE 


ILIO-HYPOGAS- 
TRIC    NERVE 


ILIO-INGUINAL 

NERVE 


Position  of  the  kidney  with  reference  to  the  posterior  abdominal  wall.      The  dotted  line 
represents  the  position  of  the  left  kidney.     (Testut.) 


size  ;iinl  position,  except  (lie  lower  end  of  the  right  kidney  in  some 
thin  patients.  They  approach  the  surface  most  nearly  below  the  twelfth 
rib  and  to  the  outer  side  of  the  erector  spina-  nnisele.  When  palpable 
they  may  lie  best  fell  from  in  front  just  below  the  costal  margin  and 
external  to  tin-   rectus  muscle,  while  the  other  hand   presses  forward 

from   behind,    below    the   last    rib. 

The  vertical  line  perpendicular  to  the  middle  of  Poupart's  ligament, 

which  marks  off  the  regions  of  the  abdomen,  cuts  the  kidney  longitudi- 
nally, 10  thai  one-third  of  it  lie-;  to  (he  outer  side  and  two-thirds  to  the 
inner  side.  The  infracostal  plane,  connecting  the  lowest  points  of  (he 
tenth   00  tal   cartilages,  CUtS  the  lower  ends  of  the  kidneys,  though  it  is 


380  THE  ABDOMEN 

not  infrequently  above  the  lower  end  of  the  left  kidney.  Hence  the  kid- 
neys are  found  in  the  following  regions:  epigastric,  hypochondriac, 
umbilical,  and  lumbar,  but  mainly  in  the  two  former  and  little  or  none 
in  the  lumbar  region,  where  they  are  often  incorrectly  thought  of  as  being. 
In  the  female  and  the  child  they  are,  as  a  rule,  slightly  lower,  often  reach- 
ing the  level  of  the  iliac  crest.  In  the  male  also  they  are  not  infrequently 
lower  than  normal.  In  most  cases  the  right  kidney  is  about  12  mm. 
(i  in.)  lower  than  the  left,  especially  at  the  upper  end,  but  exceptions  are 
common.  With  these  modifications  in  mind,  we  may  say  that  the  kidneys 
correspond  to  the  last  thoracic  and  the  first  two  or  three  lumbar  vertebrae. 
The  left  kidney  extends  from  the  level  of  the  lower  end  of  the  eleventh 
thoracic  spine  to  the  third  lumbar  spine. 

The  position  of  the  kidney  may  be  indicated  posteriorly  by  a  parallelo- 
gram whose  upper  and  lower  ends  are  drawn  horizontally  outward 
from  the  two  latter  points,  about  10  or  11.5  cm.  (4  or  4J-  in.)  apart,  while 
the  sides  are  drawn  vertically  2.5  cm.  (1  in.)  and  9.5  cm.  (3|  in.)  from  the 
spines  (Morris).  The  outer  border,  therefore,  reaches  a  point  8.5  to  10 
cm.  (3|  to  4  in.)  from  the  lumbar  spines.  The  twelfth  rib  crosses  the 
position  of  the  kidney  in  such  a  way  that  one-third  or  more  of  the  organ 
is  above  it,  under  cover  of  the  thoracic  wall.  This  rib  is  sometimes 
resected  in  operations  upon  the  kidneys  in  order  to  gain  more  room,  and 
with  care  it  may  be  done  without  risk  to  the  pleura.  But  in  one  case 
with  rudimentary  twelfth  rib,  the  eleventh  rib  was  removed  for  the 
twelfth,  the  pleura  opened,  and  death  resulted.  The  eleventh  rib  overlaps 
the  upper  pole  of  the  left  kidney,  and  the  tips  of  the  transverse  processes 
of  the  first  and  second  and  often  the  third  lumbar  vertebrae  overlap 
the  mesial  border  of  both  kidneys.  The  lower  end  of  the  right  kidney  is, 
on  the  average,  2.5  to  3.5  cm.  (1  to  1|  in.)  above  the  iliac  crest  behind 
and  the  level  of  the  umbilicus  in  front,  hence  the  kidneys  lie  higher  than 
often  supposed. 

In  front  the  upper  ends  of  the  kidneys  about  correspond  to.  the 
interchondral  articulation  of  the  sixth  and  seventh  costal  cartilages, 
and  they  extend  downward  from  here  10  or  11.5  cm.  (4  or  4^  in.),  i.  e., 
to  2.5  cm.  or  so  above  the  umbilicus.  The  shortest  distance  between  the 
two  kidneys  above  is  about  6  cm.  (2^  in.).  The  hilum  is  about  5  cm. 
from  the  median  line  and  opposite  the  first  lumbar  spine.  Owing  to 
the  oblique  position  of  the  kidneys,  the  axis  sloping  downward  and 
outward,  the  lower  pole  of  the  organ,  or  the  centre  of  the  lower  end,  is 
1  to  2.5  cm.  farther  from  the  median  line  than  the  upper  pole,  which  is 
5  cm.  (2  in.)  from  it.  The  inner  border  of  the  right  kidney  lies  very 
close  to  the  vena  cava,  that  of  the  left  kidney  2.5  cm.  (1  in.)  or  more 
from  the  aorta. 

The  slight  downward  movement  (12  mm.  [^  in.],  Holden)  of  the  kidneys 
in  inspiration  or  their  lower  position  in  accumulations  in  the  pleura  are 
accounted  for  by  the  relation  of  the  kidneys  to  the  diaphragm  and  to 
the  organs  like  the  spleen  and  liver,  which  move  with  it.  The  kidneys  also 
lie  slightly  lower  (about  1  to  1.5  cm.)  in  the  standing  than  in  the  reclining 
position. 


THE  ABDOMINAL  VISCERA 


381 


Posterior  Relations  (Figs.  129  and  130). — The  kidneys  lie  upon  the 
diaphragm  above,  and  the  quadratus  lumborum,  transversalis,  and  the 
outer  border  of  the  psoas  below,  the  muscles  being  covered  by  their 
respective  fascia?.  Intervening  between  the  quadratus  muscle  and  the 
kidney  are  the  last  thoracic,  iliohypogastric,  and  ilio-inguinal  nerves 
and  the  first  lumbar  vessels,  all  of  which  pass  obliquely  outward 
and  downward,  and  may  be  met  with  in  exposing  the  kidneys  from 
behind.  The  last  thoracic  nerve  indicates  the  lower  end  of  the 
diaphragm,  above  which  it  is  not  safe  to  incise.  The  area  of  contact 
with  the  diaphragm  is  larger  on  the  left  than  on  the  right  side, 
owing  to  the  higher  position  of  the  left  kidney.  But  on  both  sides 
it   is  of  great  importance,   as  the  kidney  is  here  in  close  relation  to 

Fig.  130 


LUMB.    MUSCLE 
CAPS.    AOIP. 

PSOAS   MUSCLE 


Topography  of  the  kidney  seen  From  behind.     The  outlines  of  the  quadratus  lumborum  and 
tor  ipinae  are  shown,     The  portion  of  the  psoas  arising  from  the  transverse  processes  have 
boon  removed.      II"'  nxlit  tw<-lftli  iil>  it    bortei  than  usual. 


the  pleura,  whose  lower  Limit  extends  nearly  horizontally  from  the 
lower  border  of  the  twelfth  thoracic  vertebra,  meeting  the  twelfth  rib 
about  8.7  cm.  <-'>\  in.)  from  the  median  line  ;ni<l  the  eleventh  rib  about 
.")  cm.  (2  in.)  farther  laterally.  II'  ;i  marked  hiatus  diaphragmaticus 
tbove  the  lig.  arcuatum  ext.  between  the  vertebral  and  costal 
portions  of  the  diaphragm,  (Ik-  kidney  may  come  in  contact  with  the 
mbpleural  tissue.  Tin-  relationship  of  the  kidney  and  pleura  explains 
(] )  tin-  frequency  of  perforation  of  perinephritic  abscesses  into  the  pleura, 
e  pecially  on  tin-  left  ide,  ;i  leriou  complication,  and  (2)  tin'  danger  of 
opening  the  pleura  in  operating  upon  the  kidney,  especially  if  (he  last 
ril)  should  be  rudimentary  and  the  eleventh  rib  be  mistaken  lor  it,  from 
failure  to  count  the  ribs.  \  a  rule,  tin-  incision  may  l»e  safely  carried 
just  below  the  lower  honler  of  the  twelfth  rib,  but  it  inn,!  lie  remembered 


382 


THE  ABDOMEN 


that  sometimes  that  part  of  the  pleura  which  extends  below  the  twelfth 
rib  reaches  beyond  the  lateral  margin  of  the  quadratics  lumborum, 
under  otherwise  normal  conditions.  A  thirteenth  rib  would  contract  the 
space  available  for  the  lumbar  approach  to  the  kidneys. 

The  Anterior  Relations  (Figs.  114,  121,  123,  and  131). — The  anterior 
relations  of  the  two  kidneys  are  different.  In  front  of  the  right  kidney 
is  the  liver  (renal  impression)  in  the  upper  half,  the  ascending  colon  in 
the  lower  half,  and  the  second  portion  of  the  duodenum  along  the  inner 
margin.  The  following  viscera  lie  in  front  of  the  left  kidney  in  the  posi- 
tions indicated:  The  stomach  in  the  upper  third,  the  splenic  vessels  and 

Fig.  131 


ADRENAL  GLAND 


REA  OF  RIGHT 
KIDNEY   UN- 
COVERED  BY 
PERITONEUM 


FOURTH    PORTION 
OF  DUODENUM 


LEFT  RENAL  VEIN 


THIRD   LUMBAR 
VERTEBRA 

PSOAS  MUSCLE  (EX- 
TERNAL border) 


Relations  of  the  anterior  surface  of  the  kidney  (semidiagrammatic). 


pancreas  in  the  middle  third,  and  the  descending  colon  in  the  outer 
part  of  lower  third,  while  along  the  upper  half  of  the  outer  border  lies 
the  spleen.  'Abscess  of  or  about  the  kidney  may  involve  the  other  organs 
in  contact,  such  as  the  liver,  spleen,  or  pancreas;  or  perforate  and  open 
into  the  colon,  duodenum,  or  stomach.  The  above  relations  are  also 
important  to  remember  in  nephrectomy.  In  the  case  of  tumors  or  other 
enlargements  of  the  kidney  the  resonant  colon  is  pushed  forward  in  front 
of  them,  hence  there  is  tympanitic  resonance  in  front.  Inflammatory 
swellings  of  the  kidney  have  but  little  movement  with  respiration,  tumors 
may  move  considerably,  and  they  are  rounded  and  not  notched  like  the 
anterior  margin  of  the  spleen,     They  often  maintain  the  shape  of  the 


THE  ABDOMINAL  VISCERA  383 

kidney  and  are  usually  separated  from  the  liver  dulness  by  a  resonant 
area.  If  large,  they  may  compress  the  spermatic  vein  and  cause  varico- 
cele. The  position  of  the  kidneys  under  the  spleen  or  liver  explains 
how  enlargement  or  displacement  of  these  organs  displace  the  kidneys 
downward. 

Relations  of  the  Kidney  to  the  Peritoneum. — The  above  viscera  in 
relation  to  the  anterior  surface  of  the  kidney,  with  the  exception  of  the 
liver  and  stomach,  intervene  between  the  kidney  and  the  peritoneum, 
so  that  the  latter  covers  only  a  limited  area  of  the  anterior  renal  surface. 
This  area  is  somewhat  greater  in  the  right  kidney  than  in  the  left.  The 
peritoneum  covering  the  left  kidney  is  derived  from  that  of  both  the  lesser 
and  greater  peritoneal  sacs.  The  peritoneal  covering  is  readily  stripped 
from  the  kidney.  According  to  Lange,  the  distance  between  the  lateral 
edge  of  the  quadratus  muscle,  internally,  and  the  point  where  the  peri- 
toneum, external  to  the  kidney,  touches  the  parietes,  is  considerable, 
but  is  less  on  the  left  side  by  at  least  1  cm.  It  is  in  this  space  that  we 
expose  the  kidney  by  the  lumbar  incision.  The  peritoneum  forms  a 
complete  covering,  mesonephron,  in  the  congenital  variety  of  floating 
kidney.  The  position  of  the  kidney  behind  the  peritoneum  allows  us  to 
reach  and  operate  upon  it  by  a  lumbar  incision  without  opening  the  peri- 
toneum, and  explains  why  rupture  is  not  so  serious  as  with  the  liver, 
spleen,  and  intestines,  as  the  extravasation  is  usually  extraperitoneal. 
Wounds  of  the  kidney  from  behind  may  readily  occur  without  injury  to 
the  peritoneum.  Although  the  kidney  is  quite  well  protected  by  thick 
muscles  behind,  its  consistence  allows  it  to  be  not  uncommonly  rup- 
tured by  external  violence  (39  per  cent,  of  visceral  lesions).  The  rupture 
has  been  shown  to  be  due  to  a  force  acting  through  the  full  vessels  and 
pelvis.  This  causes  the  kidney  to  burst  along  a  plane  which  usually 
passes  through  the  hilum  and  in  line  with  the  tubules,  which  are  trans- 
verse. The  rupture  may  open  into  the  pelvis  only,  on  the  surface  only, 
or  in  both  directions  (complete),  and  it  may  occasionally  involve  the  peri- 
toneal covering  (transperitoneal),  especially  in  children  under  ten  years, 
who  lack  the  perirenal  fat.  As  the  kidney  lies  at  the  angle  of  the  bend 
when  the  back  is  bent  far  forward,  it  may  be  caught  and  squeezed 
between  the  lower  ribs  and  the  ilium,  or  ruptured  by  a  heavy  weight 
falling  upon  the  bent  back,  while  the  kidney  is  caught  in  the  bend.  In 
renal  injuries  the  kidney  is  usually  compressed  between  the  lower  ribs 
and  the  spine. 

Fixation  of  the  Kidneys. — The  fixation  of  the  kidneys  is  due  to  the 
embedding  fat  (tunica  adiposa),  a  part  of  the  subperitoneal  connective 
tissue,  to  the  renal  vessels,  to  the  attachment  to  (he  contiguous  viscera, 

to  the  narrowing  of  the  renal  fossa-  below,  and  to  the  overlying  parietal 

peritoneum,  which  is  connected  with  the  kidney  and  i(s  "fatty  capsule." 
The  latter,  usually  scan!  al  birth,  increases  about  puberty  and  in  adult 
life,  and  is  found  mosl  abundantly  along  the  borders  and  posteriorly. 

\e;ir  the  kidney  tlii->  niiiv  assume  (lie  character  of  ;i  distinct  fascia  ( jiiri- 

renal  fateia),  which,  passing  behind  and  in  fronl  of  die  kidney,  is  attached 
to  the  fibrous  cap  ule  and  (o  die  transversalis  fascia,  spine,  diaphragm, 


384  THE  ABDOMEN 

etc.,  with  fatty  tissue  on  both  sides  of  it.  When  this  fatty  tissue  is 
absorbed,  owing  to  emaciation  from  any  cause,  the  kidney  loses  its  sup- 
port and  may  become  movable  from  slight  causes:  tight  lacing,  enlarged 
liver,  accumulations  above  the  diaphragm,  a  chronic  cough,  external 
violence,  traction  of  the  ureter,  colon,  or  duodenum  (ptosis  of  other 
viscera),  and  increased  weight  of  the  kidney.  As  the  kidney  is  also 
supported  by  intra-abdominal  pressure,  the  exciting  cause  of  a  movable 
kidney  may  be  a  relaxation  of  the  abdominal  walls,  as  the  result  of  labor, 
removal  of  tumors,  ascites,  general  muscular  weakness,  etc.  Hence  we 
can  understand  why  movable  kidney  is  so  much  more  common  in  women 
(80  per  cent,  of  cases)  than  in  men.  It  is  also  more  common  on  the  right 
side  (90  to  95  per  cent,  of  cases)  than  on  the  left,  a  fact  probably  due 
largely  to  the  liver,  pressed  down  upon  it  by  tight  lacing  and  hammering 
on  the  kidney  with  each  inspiration,  as  well  as  to  the  firmer  fixation  of  the 
left  kidney.  The  excursion  of  a  movable  kidney  is  limited  by  the  length 
of  its  vessels.  These  may  become  lengthened  and  allow  it  to  slip  down 
far  enough  behind  the  peritoneum  on  deep  inspiration,  so  that  (1st  degree) 
its  lower  pole  is  palpable,  (2d)  the  entire  kidney  is  palpable,  and  (3d)  it 
may  be  retained  by  the  fingers  below  the  costal  margin  in  front.  The 
symptoms  of  a  movable  kidney  are  due  largely  to  the  traction  upon  its 
nerves,  its  vessels,  the  ureter  (kinking  it),  and  the  gastro-intestinal  tract, 
especially  the  duodenum,  through  direct  attachment,  or  through  the 
peritoneum.  In  floating  kidney  the  mesonephron,  or  peritoneal  pedicle 
containing  the  unduly  long  bloodvessels,  allows  a  wider  excursion,  to 
the  anterior  abdominal  wall,  the  iliac  fossa,  or  even  to  the  pelvic  cavity. 
The  longer  the  pedicle  the  greater  the  danger  of  its  torsion  and  the 
resulting  atrophy,  gangrene,  or  hydronephrosis  of  the  kidney.  Movable 
kidneys,  when  the  symptoms  demand  it,  may  be  fixed  by  suture  and 
other  means,  through  a  lumbar  incision. 

It  is  through  this  fatty  capsule  of  a  canary-yellow  color,  which,  if  exces- 
sive, protrudes  hernia-like  into  the  incision,  that  we  work  our  way  by 
blunt  dissection  in  order  to  expose  the  kidney  through  the  lumbar  incision. 
The  looseness  of  this  tissue  permits  the  ready  enucleation  of  the  kidney, 
except  in  cases  where  it  has  become  adherent  to  the  kidney  as  the  result  of 
inflammation.  If  scanty,  the  fatty  capsule  often  appears  as  a  fascial 
membrane,  which  may  be  mistaken  for  peritoneum  or  transversalis 
fascia.  Again,  it  is  in  this  tissue  that  perinephritic  abscesses  develop,  from 
disease  of  the  kidney  or  neighboring  parts  or  from  injury.  The  spread  of 
such  abscesses  we  can  understand  from  the  looseness  of  this  tissue  and 
its  continuity  with  the  adjoining  subperitoneal  connective  tissue.  As 
such  abscesses  are  in  contact  with  the  diaphragm  above,  they  are  not 
unlikely  to  perforate  this  and  break  into  the  pleura.  Curiously  enough, 
they,  as  well  as  abscesses  of  the  kidney,  rarely  perforate  the  peritoneum. 
For  further  accounts  of  their  course,  see  Posterior  Relations  of  the  Kid- 
ney (p.  381)  and  Abdominal  Walls,  Lumbar  Region  (p.  314). 

Misplacements  and  Varieties  of  the  Kidneys. — One,  more  often  the 
left,  less  often  both  kidneys,  may  be  congenitally  misplaced.  A  mis- 
placed kidney  is  often  misshapen,  lobulated,  as  in  the  fetus,  or  hourglass, 


THE  ABDOMINAL  VISCERA  385 

horseshoe,  or  disk-shaped,  etc.  Congenital  displacement  is  downward, 
as  a  rule,  so  that  the  organ  lies  in  the  iliac  fossa,  on  the  pelvic  brim,  or 
even  in  the  pelvis.  It  may  give  rise  to  serious  error  in  diagnosis  or 
treatment.  One  kidney  is  sometimes  much  smaller  than  the  other 
(1  in  138),  or  both  may  be  fused  together  as  a  single  "disk-like"  mass 
(1  in  12,'000  cases),  with  one  or  two  pelves  and  ureters,  or  more  often  as 
a  horseshoe  kidney  (1  in  1000  cases)  joined  at  their  lower  ends  across 
the  median  line  by  kidney  or  connective  tissue.  When  joined  by  con- 
nective tissue  this  is  no  bar  to  operation,  even  to  removal  of  half  of  the 
kidney.  Rarely  there  may  be  either  one  kidney  or  extreme  congenital 
atrophy  of  the  other  one  (1  in  2650  cases)  and  extremely  rarely  three 
kidneys.  The  presence  of  an  abnormally  placed  renal  mass  should  be  so 
suggestive  of  a  single  kidney  as  to  prevent  nephrectomy  until  a  second 
kidney  has  been  found  present  (Morris). 

The  Hilum. — The  hilum  of  the  kidney  looks  forward,  more  or  less 
inward,  and  slightly  downward.  Its  posterior  lip  is  thick  and  nearer 
to  the  median  line.  Of  the  principal  structures  which  enter  or  emerge 
from  the  sinus  at  this  slit-like  aperture,  the  vein  is  in  front,  the  artery 
behind  it,  and  the  pelvis  of  the  ureter  the  most  posterior  and  inferior. 
Hence  the  pelvis  is  most  accessible  to  exposure  from  behind. 

The  Vessels. — The  vessels  form  the  important  element  of  the  pedicle 
in  nephrectomy,  and  are  to  be  ligated  together  or  separately  and  apart 
from  the  ureter  if  possible.  In  this  connection  it  is  well  to  remember  that 
the  left  artery  and  right  vein  are  shorter  than  their  fellows,  and  the  short- 
ness of  the  right  renal  vein  sometimes  embarrasses  the  operator  in  a 
nephrectomy  or  other  operation  on  the  right  kidney,  and  may  make  it 
difficult  or  impossible  to  deliver  the  kidney  onto  the  loin,  through  a 
lumbar  incision.  The  renal  arteries,  about  the  size  of  the  brachial, 
divide  into  about  three  large  branches  before  entering  the  hilum,  and  in 
nearly  50  per  cent,  of  cases  they  present  irregularities  in  number,  place 
of  entry,  etc.  Frequently  one  or  more  additional  arteries  are  given  off 
from  the  aorta,  or  the  neighboring  branches,  and  pass  to  the  hilum,  the 
anterior  surface,  or  either  end  of  the  kidney,  most  often  to  the  lower  end 
inferior  renal  artery). 

The  veins  are  less  often,  but  not  infrequently,  irregular.  They  may 
accompany  the  additional  arteries  at  either  end  of  the  kidney,  or  a 
branch  may  be  found  entering  the  hilum,  with  a  branch  of  the  artery, 
behind  the  pelvis.  There  would  be  danger  of  wounding  the  latter  vessels 
in  opening  the  pelvis  from  behind  for  exploration  or  the  extraction  of  a 
calculus.  The  frequency  of  the  above  irregularities  in  the  vessels  should 
be  borne  in  mind  in  a  nephrectomy,  for  several  eases  are  recorded  where 
supernumerary  renal  vessels,  not  entering  at  the  hilum,  have  given  rise 
ions,  it"  not  fatal,  hemorrhage. 

Owing  to  the  deep  position  of  the  kidneys,  they  and  their  vessels  are 
liable  to  be  pressed  upon   in  (lie  snpine  position  by  the  viseera   as  well 

as  by  tumors  or  tin-  gravid  uterus.    Hence  their  secretory  Functions  are 
probably  influenced  by  changes  in  posture,  so  that  tin-  latter  might 
!><■  utilized  in  therapeutics.    Congestion  of  tin-  renal  vessels  may  be  due 
25 


386 


THE  ABDOMEN 


to  other  causes  than  direct  pressure,  i.  e.,  impeded  circulation  through 
the  lungs  or  heart,  inflammation,  etc.  Long-continued  congestion 
begets  increase  of  the  interstitial  fibrous  tissue,  the  contraction  of  which 
later  on  produces  cirrhotic  or  atrophic  kidney,  just  as  similar  conditions 
in  the  liver  produce  cirrhosis  of  the  liver.  Owing  to  the  anastomosis 
between  the  small  vessels  of  the  surface  of  the  kidney  and  the  branches 
of  the  lumbar  vessels,  bloodletting,  cupping,  or  counterirritation  in  the 
loins  may  relieve  congestion  of  the  kidney.  In  order  to  improve  this 
anastomosis,  decapsulation  has  been  performed  in  chronic  nephritis. 
In  time,  however,  with  the  contraction  of  the  new  adhesions,  the  tem- 
porary improvement  disappears.    The  lymphatics  (both  superficial  and 


Fig.  132 


Fig.  133 


CORRECT  INCISIO 


MAJOR  CALYX 


Lateral  view  of  the  kidney  with  its  pelvis 
distended,  showing  the  correct  line  of  incision 
through  the  lateral  portion  of  the  posterior 
pyramids,  parallel  to  and  1  cm.  from  the  white 
line. 


Transverse  section  of  the  kidney,  showing 
the  two  arterial  systems,  the  larger  anterior 
and  the  smaller  posterior.  The  line  of  correct 
incision  passes  through  into  the  pelvis  between 
these  two  vascular  trees. 


deep)  accompany  the  bloodvessels,  especially  the  vein,  and  enter  the 
nodes  lying  on  the  corresponding  side  or  in  front  of  the  aorta,  and 
below  rather  than  above  the  renal  vessels.  The  superficial  subcapsular 
lymphatics  connect  freely  with  the  lymphatics  of  the  perirenal  adipose 
tissue. 

Nerves.  —The  nerves  of  the  kidney  come  from  the  renal  plexus  which 
is  derived  from  the  solar  and  aortic  plexuses  and  the  lesser  splanchnic 
nerves.  The  communication  between  the  renal  and  spermatic  plexuses 
accounts  for  the  radiation  of  the  pain  of  a  renal  colic  to  the  testicle  and 
the  peculiar  testicular  nausea  from  pressure  upon  a  movable  kidney,  etc. 
The  nausea  and  vomiting,  and  other  symptoms  of  intestinal  colic,  or 


THE  ABDOMINAL  VISCERA  387 

the  rectal  and  vesical  tenesmus,  sometimes  present  in  a  renal  colic  or  a 
movable  kidney  (Dittel's  crises),  are  accounted  for  by  the  relation  of  the 
nerves  of  the  kidney  with  the  ganglia  supplying  the  intestines  and  bladder. 
On  account  of  the  association  between  the  renal  plexus  and  the  upper 
lumbar  nerves,  pain  in  renal  colic  may  radiate  along  the  latter  and  be 
referred  to  the  outer  border  of  the  right  rectus  in  the  spino-umbilical  line, 
simulating  appendicitis,  or  the  testicle  maybe  drawn  up  by  the  cremaster. 
On  the  other  hand,  caries  of  the  upper  lumbar  vertebrae  may  be  mis- 
taken for  renal  calculus,  on  account  of  the  location  of  the  pain.  The 
most  sensitive  parts  of  the  kidney  are  the  pelvis  and  the  capsule,  hence 
renal  pain  may  depend  not  only  upon  infection,  irritation  of  a  calculus, 
etc.,  but  upon  tension,  the  relief  of  which,  and  often  of  congestion,  fol- 
lows splitting  the  capsule  with  or  without  puncture  of  the  kidney.  Occa- 
sional cures  of  various  forms  of  nephritis  have  been  obtained  in  this  way. 

The  kidney  is  surrounded  by  a  thin  but  strong  fibrous  capsule.  In  the 
healthy  condition  this  capsule  can  be  'peeled  off  from  the  kidney,  leaving 
its  surface  smooth,  for  the  two  are  only  connected  by  a  delicate  reticulum 
of  fibrous  tissue  and  minute  vessels.  In  a  cirrhotic  kidney,  and  some 
other  lesions  of  the  kidney,  this  reticulum  is  thickened  so  that  it  is  difficult 
to  peel  off  the  capsule,  and^the  renal  surface  is  left  very  rough  when  it 
is  so  removed.  Hence  these  facts  are  made  use  of  in  autopsies  as  indi- 
cating a  healthy  or  a  diseased  kidney.  In  some  cases  of  nephrectomy, 
when  it  is  difficult  to  shell  out  the  kidney  from  its  fatty  capsule,  owing 
to  previous  inflammation,  it  may  be  easier  to  remove  it  from  within  its 
fibrous  capsule,  though  the  hemorrhage,  from  oozing  of  the  small  vessels, 
is  more  profuse. 

Operations  on  the  Kidney. — The  kidney  is  incised  (nephrotomy)  along 
its  outer  border  for  exploration,  drainage,  relief  of  tension,  or  removal 
of  a  calculus  (nephrolithotomy).  In  incision  of  the  kidney  it  is  to  be 
borne  in  mind  that  the  blood  supply  of  most  kidneys  is  divisible  into 
two  systems  completely  separated  by  the  renal  pelvis,  an  anterior  sys- 
tem carrying  three-fourths  of  the  blood  and  a  posterior  system  carry- 
ing one-fourth.  The  line  of  safety  for  incision  is  the  longitudinal  line 
Ix  tween  these  two  systems,  along  the  lateral  border,  1  cm.  posterior  to 
the  white  line  of  B  rod  el,  which  is  noticed  when  the  pelvis  is  distended. 
By  palpating  at  the  hilum  we  can  feel  on  which  side  are  the  lesser  number 
of  vessels,  usually  posteriorly  (Figs.  132  and  133).  The  entire  organ 
may  be  removed  (nephrectomy),  or  it  may  be  secured  in  its  normal 
position  by  suturing  (nephrorrhaphy)  when  movable. 

The  kidney  is  exposed  for  these  purposes  by  B  vertical  or,  preferably, 
an  obliquely  transverse  Lumbar  incision  in  the  iliocostal  space  between 
the  lower  ribs  and  the  iliac  crest.  To  gain  additional  room,  the  incision 
may  be  prolonged  forward  as  far  as  the  rectus  muscle,  or  forward  and 
upward  toward  the  umbilicus  from  just  above  the  anterior  iliac  spine, 
or  enlarged  by  making  ;i  flap.  In  aephrectomy  for  a  very  large  tumor, 
some  prefer  the  transperitoneal  method,  incising,  as  a  rule,  in  the  cor- 
tonding  semilunar  line.  In  the  latter  operation  the  kidney  should 
b  •  reached   from   the  outer  side  of  the  colon  to  avoid   the  colic  vessels. 


388  THE  ABDOMEN 

For  the  details  of  the  lumbar  incision,  see  Lumbar  Region,  Posterior 
Abdominal  Wall,  page  315. 

The  Ureters. — The  ureters  are  about  27  to  30  cm.  (11  to  12  in.)  long 
in  the  male.  The  diameter  is  not  uniform,  but  varies  between  3.2  and  8 
mm.,  and  between  its  narrow  points  it  shows  spindle-shaped  enlargements. 
Above  they  spring  from  a  funnel-shaped  enlargement,  the  pelvis,  which, 
passing  out  at  the  back  of  the  hilum,  where  it  may  be  reached  and  opened, 
narrows  as  it  descends  until  it  attains  the  cylindrical  character  of  the 
ureter  opposite  the  lower  end  of  the  kidney.  A  constriction  about  7  cm. 
(2|  in.)  below  the  kidney  forms  the  narrowest  point  of  the  ureter.  The 
second  constriction  is  at  the  bend  at  the  pelvic  brim.  The  third  constric- 
tion, and  next  to  narrowest  point,  is  at  its  lower  opening  and  in  its  passage 
through  the  bladder  wall,  hence  calculi  which  have  passed  the  other 
constrictions  are  likely  to  be  arrested  here,  where  they  can  be  readily 
felt  through  the  vagina  in  the  female.  In  cases  of  gradual  dilatation,  the 
ureters  are  capable  of  great  distention,  to  the  size  of  the  thumb  or  even 
that  of  the  small  intestine.  This  is  not  due  to  a  backward  flow  from  the 
bladder,  but  to  an  obstruction  in  the  lower  urinary  passages,  causing 
distention  and  perhaps  frequent  contraction  of  the  bladder,  thus  prevent- 
ing the  emptying  of  the  ureter,  for  the  ureters  cannot  be  emptied  when 
the  walls  of  the  bladder  contract  or  its  cavity  is  too  distended.  The 
oblique  passage  of  the  ureter  through  the  bladder  walls  downward  and 
inward  for  12  to  18  mm.  (§•  to  f  in.)  acts  as  a  valve,  preventing  reflux 
into  the  ureter,  so  that  the  fuller  the  bladder  the  more  tightly  is  the 
ureter  mouth  closed. 

Course. — The  ureters  lie  about  9  to  11  cm.  (3^  to  4^  in.)  apart  at  their 
commencement  and,  converging  slightly  as  they  descend  in  the  umbilical 
(not  the  lumbar)  region,  they  are  about  6.7  to  8.5  cm.  (2|  to  3^  in.) 
apart  as  they  cross  the  pelvic  brim,  near  the  sacro-iliac  joint,  to  enter  the 
pelvis.  They  then  diverge,  following  the  curve  of  the  lateral  pelvic  wall 
to  the  level  of  the  ischial  spine.  In  this  part  of  their  course  they  lie  in 
front  of  the  internal  iliac  arteries  and  cross  the  obturator  vessels  and 
nerves.  They  then  turn  inward  and  in  the  male  lie  in  the  parietal  attach- 
ments of  the  posterior  false  ligaments  of  the  bladder,  in  which  they  run 
forward  and  inward  to  reach  the  bladder  3.5  to  4.5  cm.  (If  to  1£  in.) 
apart  and  the  same  distance  behind  the  prostate.  In  the  female  they  lie 
in  the  base  or  root  of  the  broad  ligament  12.5  to  18.5  mm.  (J  to  f  in.) 
external  to  the  cervix  uteri.  Here  they  are  crossed  in  front  by  the  uterine 
arteries  and  pass  through  the  uterine  plexus  of  veins  (Figs.  149  and  150). 
They  then  cross  obliquely  the  upper  third  of  the  vagina,  inclining  forward 
from  the  lateral  vaginal  wall  to  the  vesicovaginal  interspace,  and  enter  the 
bladder  wall  6  mm.  below  the  anterior  fornix  of  the  vagina.  Hence,  in  the 
female,  a  stone  impacted  in  the  lower  6  to  7.5  cm.  (2%  to  3  in.)  of  the  ureter 
may  be  palpated  through  the  vagina  and  an  extensive  carcinoma  of  the  cer- 
vix or  upper  end  of  the  vagina  may  involve  and  obstruct  the  ureters.  In 
the  male  their  lower  extremities,  if  containing  a  calculus  or  thickened  by 
disease,  can  be  palpated  through  the  rectum  with  some  difficulty.  Their 
course  and  relations  in  the  female  pelvis  are  of  vital  importance  in  opera- 


PLATE  XXXVI 


FIG.   134 


POST     FALSE 
LIGAMENT 
OF  BLADDER 


BECTO-VES 
CAL  POUCH 


fOBLITER- 
ATED    HY 
POGAS 
TRIC 
ARTERY 


SPERMATIC 
VESSELS 


VAS    DEFERENS 
INT.    ABDOMI- 
NAL   RING 
DEEP    EPIGAS- 
TRIC   ARTERY 


Pelvic  Portion  of  the  Ureters,  Formation  of  the  Spermatic  Cord, 
Rectovesical  Pouch,  Pelvic  Vessels,  etc.     (Testut.) 

Male,  seen  from  in  fronl  and  above,  the  bladder  being  pulled  forward. 


THE  ABDOMINAL  VISCERA  389 

tions  on  the  female  pelvic  organs,  and  many  cases  are  recorded  where  the 
ureter  has  been  injured  in  operations  on  these  organs.  In  such  opera- 
tions the  distance  between  the  ureters  and  the  cervix  is  considerably 
increased  if  the  uterus  is  pulled  upward  and  forward.  As  a  result  of  these 
injuries  several  methods  have  been  successfully  employed  of  uniting  the 
divided  ends  of  the  ureters  or  re-implanting  them  into  the  bladder  or 
colon  when  divided  low  down.  They  have  also  been  attached  to  the 
surface  for  permanent  drainage  in  a  few  cases. 

The  relations  of  the  ureters  are  of  importance  for  the  purpose  of  find- 
ing or  avoiding  them  as  occasion  requires.  They  cross  obliquely  the 
psoas  muscles  and  the  genitocrural  nerves,  being  connected  loosely 
with  the  muscle  but  firmly  with  the  external  surface  of  the  peritoneum. 
From  the  latter  circumstance  they  can  be  readily  found,  for,  if  the  peri- 
toneum is  stripped  up  from  the  psoas,  the  ureters  remain  attached  to  the 
peritoneum  1.2  to  2.5  cm.  (^  to  1  in.)  from  the  attachment  of  the  latter 
to  the  vertebra?  on  the  left  side  and  a  little  more  on  the  right  side,  where 
the  ureter  is  displaced  outward  by  the  vena  cava.  Psoas  abscess  has  been 
known  to  discharge  through  the  ureter.  On  section  between  the  second 
and  third  lumbar  vertebrae  the  right  ureter  is  4  cm.  from  the  parietal 
peritoneum  external  to  the  outer  border  of  the  kidney;  the  left  is  6  cm. 
distant. 

In  their  course  in  the  abdomen  the  ureters  are  crossed  anteriorly  by  the 
spermatic  (or  ovarian)  and  colic  vessels.  The  vena  cava  is  almost  in 
contact  with  the  right  ureter  on  its  mesial  aspect,  while  the  left  is  sepa- 
rated from  the  aorta  by  2.5  cm.  (1  in.)  above  and  1.2  cm.  {\  in.)  below, 
opposite  the  aortic  bifurcation.  On  the  right  side  the  ureter  is  in  near 
relation  to  the  appendix,  and  when  the  latter  points  inward  and  is  adher- 
ent posteriorly  the  two  may  be  in  contact,  though  the  lower  end  of  the 
ileum  often  intervenes.  The  possibility  of  injuring  the  ureter  should  be 
remembered  in  operations  on  the  appendix.  Near  the  pelvic  brim  it 
crosses  the  common  iliac  artery  close  to  its  bifurcation,  or  the  beginning 
of  the  external  iliac  (more  often  on  the  right  side),  and  lies  behind  the 
sigmoid  loop  on  the  left  side  and  the  lower  end  of  the  ileum  on  the  right. 
These  relations  are  important  in  ligation  of  the  iliac  arteries. 

In  the  pel o is  the  left  ureter  is  lateral  to  the  sigmoid  mesocolon.  At 
the  bladder  the  ureter  lies  below  the  obliterated  hypogastric  artery,  and 
in  the  male  i^  crossed  superiorly  and  internally  by  the  vas  deferens, 
which  thus  comes  to  lie  between  it  and  the  bladder.  The  free  end  of 
the  seminal  vesicle  overlaps  it  from  below.  The  inner  openings  in  the 
bladder  are  about  2.5  cm.  (1  in.)  from  one  another  and  from  the  vesical 
outlet. 

Varieties  and  Malformations.  -There  may  be  only  a  single  ureter 
from  a  Fused  kidney,  or  two  or  even  three  ureters  may  arise  from  one 
kidney,  from  the  late  union,  or  non-union,  of  the  middle  pelves  which 

form  tin-  common  pelvis.  Two  medformations  may  exist  as  (he  cause  of 
hydronephrosis:  (\)  a  kind  <>f  congenital  valve  at  the  commencement 
of  th<-  ureter;  and  (2)  an  origin  of  the  ureter  above  the  lower  end  of  the 
pelvis,  so  that  when  the  latter  fills,  it  may  press  upon,  narrow,  or  close 


390  THE   ABDOMEN  . 

the  valve-like  opening  of  the  ureter.  In  the  latter  cases  the  ureter  appears 
to  come  from  the  upper  or  middle  instead  of  the  lower  of  the  two  or  three 
middle  pelves  that  make  up  the  common  pelvis. 

The  flow  of  urine  through  the  ureters  is  due  to  the  'peristaltic  con- 
traction of  their  muscular  coats,  and  occurs  at  regular  intervals.  It  may 
be  aided  by  gravity  in  the  erect  position. 

Tourneur's  point  is  at  the  intersection  of  a  line  connecting  the  tips  of 
the  twelfth  ribs  and  of  one  drawn  vertically  from  the  junction  of  the 
inner  and  middle  thirds  of  Poupart's  ligament.  It  represents  the  com- 
mencement of  the  ureter,  the  level  of  origin  of  the  spermatic  or  ovarian 
artery,  and  the  lower  extremity  of  the  kidney.  The  course  of  the  abdomi- 
nal portion  of  the  ureter  is  represented  by  a  line  from  this  point  to  the 
junction  of  the  upper  and  middle  thirds  of  the  line  for  the  iliac  arteries 
(Morris).  In  this  line  we  may  palpate  for  tenderness  in  suspected  lesions 
of  the  ureter.  The  abdominal  portion  of  the  ureters  (i.  e.,  above  the  pelvic 
brim)  may  be  exposed  by  an  incision  used  to  expose  the  kidney,  passing 
obliquely  from  near  the  costovertebral  angle  toward  the  anterior  superior 
iliac  spine  and  then  curving  toward  the  umbilicus  or  running  a  little 
above  Poupart's  ligament;  or,  by  an  incision  like  that  for  the  common 
iliac  artery,  carried  farther  upward.  The  walls  of  the  ureter  are  about 
one  twenty-fifth  of  an  inch  thick,  composed  mainly  of  muscular  and 
fibrous  tissue. 

The  passage  of  a  renal  calculus  through  the  ureter  is  accomplished  in 
much  the  same  way  as  that  of  biliary  calculi  (p.  372)  and  with  a  similar 
intense,  intermittent  pain,  known  as  renal  colic.  They  are  most  likely  to 
be  arrested  just  above  the  constrictions  of  the  ureter.  The  ureters  have 
been  ruptured  by  external  violence.  The  resulting  extravasation  of  urine 
is  large,  retroperitoneal,  and  liable  to  suppuration,  producing  a  lumbar, 
iliac,  or  pelvic  abscess. 

The  Suprarenal  Bodies  or  Adrenals  (Figs.  114, 121). — These  are  two 
ductless  glands,  one  of  which  rests  on  the  upper  end  and  the  adjoining 
parts  of  the  anterior  surface  and  inner  border  of  each  kidney.  They 
are  separated  from  the  kidney  by  the  perinephritic  tunica  adiposa,  so  that 
changes  in  position  of  the  kidney  do  not  affect  the  suprarenals.  They 
are  larger  at  birth  than  in  the  adult,  they  atrophy  in  advanced  life,  and 
are  degenerated  in  connection  with  Addison's  disease.  They  rest  upon 
the  diaphragm  opposite  the  eleventh  and  twelfth  ribs,  and  perhaps  the 
tenth  interspace,  or  opposite  the  adjoining  portions  of  the  eleventh  and 
twelfth  thoracic  vertebrae.  An  interval  of  5  to  6.2  cm.  (2  to  2\  in.) 
separates  them  from  one  another. 

The  left  is  crescentic,  flattened  from  before  backward,  and  extends 
lower  down  than  the  right  one  along  the  inner  border  of  its  kidney,  even 
to  the  hilum.  In  front  lies  the  stomach,  separated  by  the  lesser  peri- 
toneal sac,  and  its  lower  cornu  is  crossed  by  the  pancreas  and  the  splenic 
vessels.  Externally  it  is  in  contact  with  the  upper  end  of  the  spleen.  The 
right  suprarenal  is  more  triangular,  laterally  compressed  and  vertically 
elongated,  but  reaches  no  higher  than  the  left,  owing  to  the  lower  position 
of  the  right  kidney.    It  is  related  in  front  to  both  the  inferior  and  posterior 


THE  ABDOMINAL  VISCERA  3gi 

surfaces  of  the  right  lobe  of  the  liver  (impressio  suprarenalis) ;  internally 
to  the  vena  cava,  which  slightly  overlaps  it,  and  its  inferior  angle  is 
crossed  by  the  first  bend  of  the  duodenum.  It  lies  behind  the  foramen 
of  Winslow.  The  left  suprarenal  is  covered  with  peritoneum  above, 
the  right  below.  In  a  three  months'  fetus  the  adrenal  is  much  larger 
than  and  nearly  surrounds  the  kidney,  affording  abundant  opportunity 
for  the  occurrence  of  persistent  misplaced  portions  in  the  renal  cortex 
beneath  the  capsule.  Such  adrenal  rests  may  be  the  starting  point  of 
both  benign  and  malignant  tumors  belonging  to  the  class  of  kidney 
tumors  known  as  hypernephroma. 

The  nerve  supply  of  the  suprarenals  is  remarkably  abundant,  derived 
mainly  from  the  solar  and  renal  plexuses,  with  some  branches  from  the 
phrenic  and  vagus  nerves.  Several  cysts  and  tumors  of  the  adrenals  have 
been  operated  on.  The  suprarenals  are  generally  disregarded  in  opera- 
tions on  the  kidneys,  except  that  the  blood  supply  of  the  two  is  more  or 
less  connected,  especially  on  the  left  side.  The  extract  of  these  bodies 
is  a  remarkably  strong  astringent  and  vasomotor  stimulant,  and  as  such 
is  much  used  therapeutically.  It  has  also  been  used  in  Addison's 
disease,  etc. 

Bloodvessels  of  the  Abdomen. — The  following  is  in  addition  to  the 
mention  made  under  the  several  organs  and  the  parietes : 

The  abdominal  aorta  varies  in  its  distance  from  the  ventral  surface 
in  different  individuals,  but  in  general  it  approaches  nearer  the  surface 
as  it  nears  its  bifurcation.  Hence  the  most  favorable  point  for  compres- 
sion of  the  aorta  is  just  above  the  umbilicus,  for  it  bifurcates  just  below 
and  to  the  left  of  this  point.  But  even  here  it  cannot  be  readily  felt 
or  satisfactorily  compressed  unless  the  bowels  are  quite  empty. 

Aneurysm  is  most  likely  to  occur  at  or  near  the  celiac  axis,  which  is  a 
weak  spot,  often  giving  way  in  injections  of  the  cadaver,  for  here  several 
large  branches  are  given  off,  causing  a  sudden  deviation  in  the  course 
of  the  circulation  and  a  sudden  contraction  in  the  size  of  the  aorta.  Such 
an  aneurysm  gives  rise  to  a  pulsating  tumor  in  the  epigastric  or  umbilical 
region,  but  a  tumor  of  the  organs  in  front  of  the  aorta  (pylorus,  pancreas, 
colon)  may  also  receive  a  pulsation  (not  expansile)  from  the  aorta. 
Pressure  of  the  aneurysm  on  the  diaphragm,  esophagus,  and  stomach 
may  cause  dyspnea,  dysphagia,  and  vomiting;  on  the  vena  cava,  edema 
of  the  legs;  on  the  renal  veins,  albuminuria;  on  the  lumbar  nerves,  pain 
in  the  back,  buttocks,  or  thigh;  on  the  sympathetic  plexuses,  indigestion, 
visceral  pains,  reflex  pains  in  the  lumbar  nerves,  etc. 

Many  of  the  branches  of  the  abdominal  aorta  are  of  large  size,  the 
celiac  axis  and  superior  mesenteric  are  of  the  size  of  the  common  caro- 
tid;  the  hepatic,  splenic,  and  renals  equal  the  brachial  in  size.  Aneurysm 
sometimes  occurs  on  many  of  these  branches. 

The  number  of  minute  extraperitoneal  anastomoses  between  the 
branches  of  the  parietal  vessels  (lower  intercostal,  phrenic,  lumbar, 
iliolumbar,  epigastric,  and  circumflex  iliac)  and  branches  of  vessels 
which  supply  viscera  not  entirely  covered  by  peritoneum  (liver,  kidney, 
adrenals,  duodenum,  puncreas,  ascending  and  descending  colon)  are  of 


392  THE  ABDOMEN 

great  importance  in  case  of  obstruction  to  the  arterial  supply  of  the  vis- 
cera. The  corresponding  venous  anastomoses  are  of  equal  or  greater 
importance  in  case  of  obstruction  of  either  the  vena  cava  or  the  portal 
vein.  The  parumbilical  vein  also  directly  connects  the  portal  vein 
with  the  epigastric,  and  thus,  with  the  external  iliac  veins,  may  be  of 
much  service  in  relieving  obstruction  of  the  portal  circulation,  as  in 
cirrhosis  (see  also  pp.  279  and  365).  The  above  anastomoses  explain  the 
effect  of  surface  bloodletting  and  counterirritation  in  inflammation  or 
congestion  of  the  partly  extraperitoneal  viscera. 

The  celiac  axis,  with  a  semilunar  ganglion  on  either  side,  arises  oppo- 
site the  top  of  the  first  lumbar  vertebra,  about  10  cm.  (4  in.)  above  the 
umbilicus.  The  renal  artery  arises  opposite  the  low^r  end  of  the  same 
vertebra  (that  of  the  right  side  somewhat  lower),  the  inferior  mesenteric 
about  5  cm.  (2  in.)  above  the  aortic  bifurcation,  or  3.7  cm.  (1^  in.)  above 
the  umbilicus.  The  left  renal  vein,  crossing  in  front  of  the  aorta,  to  reach 
the  vena  cava,  is  an  exception  to  the  rule  that  below  the  diaphragm  the 
large  veins  pass  behind  the  large  arteries,  while  above  the  diaphragm 
they  pass  in  front. 

Lymph  Nodes  of  the  Abdomen. — Besides  the  lymphatic  nodes  already 
noticed,  in  connection  with  the  organs,  there  is  a  central  series  of  retro- 
peritoneal lymph  nodes  arranged  around  the  aorta.  The  nodes  on  the 
sides  of  the  aorta  (juxta-aortic),  those  on  the  right  side  lying  behind  and 
in  front  of  the  vena  cava,  receive  the  lymphatics  from  the  iliac  nodes, 
the  kidneys,  genital  organs,  and  parietes.  Those  in  front  of  the  aorta 
(pre-aortic)  receive  the  lymphatics  from  the  alimentary  canal  and  its 
accessories.  The  upper  nodes  of  this  chain  grouped  about  the  origin  of 
the  superior  mesenteric  artery  and  celiac  axis  are  sometimes  called  the 
celiac  nodes,  as  distinguished  from  the  lumbar  or  lower  nodes.  Great 
enlargement  of  these  nodes  may  cause  edema  from  pressure  on  the  vena 
cava. 

Nerve  Supply  of  the  Abdominal  Viscera. — This  is  derived  from  a 
series  of  connected  plexuses  in  front  of  the  abdominal  aorta,  formed  by  the 
sympathetic  system  with  some  branches  from  the  vagus  and  phrenic  nerves. 
The  two  great  splanchnic  nerves,  descending  from  the  thorax,  end  in  the 
two  large  semilunar  ganglia,  one  on  either  side  of  the  celiac  axis.  These 
are  united  together,  and  with  many  small  surrounding  ganglia,  by  a 
network  of  fibrils  to  form  the  solar  plexus,  behind  the  stomach,  above  the 
pancreas,  between  the  adrenals,  and  in  front  of  the  aorta  and  crura  of  the 
diaphragm.  It  also  receives  twigs  from  the  vagus  and  phrenic  nerves. 
From  this  central  plexus  branch  plexuses  are  derived  which  accompany 
the  visceral  branches  of  the  aorta,  except  the  inferior  mesenteric,  to  the 
organs  which  they  supply.  The  renal  plexus  also  receives  the  least 
splanchnic  nerves.  Mesial  branches  of  the  lateral  sympathetic  cords 
form  the  aortic  plexus  in  front  of  the  aorta  between  the  superior  and 
inferior  mesenteric  arteries.  Along  the  latter  a  branch  of  this  plexus, 
the  inferior  mesenteric  plexus,  passes  to  the  viscera  supplied  by  the  artery. 
These  plexuses,  and  the  nerves  which  go  to  form  them,  communicate 
with  the  thoracic  and  lumbar  spinal  nerves,  and  thus  account  for  many 


THE  ABDOMINAL  VISCERA  393 

reflexes,  i.  e.,  the  reflex  pains  and  muscular  contractions  in  the  course 
of  the  spinal  nerves  in  cases  of  peritonitis,  etc.  (see  p.  281).  The  "sym- 
pathetic" or  reflex  pain  between  the  shoulders,  or  about  the  angles  of  the 
scapula;,  in  some  diseases  of  the  stomach  and  liver,  are  probably  due  to  a 
reflex  in  the  fourth,  fifth,  and  sixth  thoracic  nerves,  which  supply  these 
parts  and  communicate  with  the  great  splanchnic  nerves  which,  through 
the  solar  plexus,  go  to  supply  the  liver  and  stomach.  Owing  to  the 
centralization  in  the  great  nerve  plexuses  in  the  abdomen,  almost  all 
acute  troubles  in  the  abdomen  begin  with  the  same  group  of  symptoms 
(Treves).  Reflex  pain  in  the  tip  of  the  shoulder  has  already  been 
referred  to.     (See  Liver,  p.  366.) 

From  the  extent  of  these  abdominal  nerve  centres,  especially  the  solar 
plexus,  we  can  understand  what  profound  effects,  collapse,  vomiting,  and 
even  death,  may  attend  an  injury  to  them  or  the  viscera  most  closely 
associated  with  them.  Hence  the  danger  of  a  blow  over  the  pit  of  the 
stomach,  i,  e.,  over  the  solar  plexus,  which  may  even  cause  death  from 
cardiac  inhibition  without  marks  of  external  injury,  and  always  causes 
shock  out  of  all  proportion  to  the  extent  of  the  injury.  Hence,  also,  an 
injury  to  those  viscera  which  are  more  remotely  connected  with  the 
nerve  centres,  such  as  the  descending  colon,  which  is  supplied  by  the 
inferior  mesenteric  plexus,  only  indirectly  connected  with  the  solar 
plexus,  or  even  the  ascending  colon,  supplied  by  a  part  of  the  superior 
mesenteric  plexus  most  remote  from  the  centres,  is  accompanied  by 
less  serious  symptoms.  It  is  noteworthy  that  the  nearer  the  lesion  is 
to  the  stomach,  other  things  being  equal,  the  more  profound  are  the 
nervous  phenomena  produced.  Distant  pain  in  disease  of  the  abdominal 
viscera  is  not  necessarily  reflex,  but  may  be  due  to  pressure.  Thus  pain 
in  the  knee  may  be  due  to  the  pressure  of  the  sigmoid  flexure,  distended 
with  feces  or  affected  with  cancer,  upon  the  obturator  nerve. 


CHAPTER    V. 

PELVIS  AND  PERINEUM 
THE  PELVIS. 

We  have  already  studied,  in  a  preceding  section,  the  upper  part  or 
false  pelvis  which  supports  some  organs  and  attaches  many  muscles  of 
the  abdomen.  It  remains  to  study  the  true  pelvis  and  its  viscera.  The 
external  or  superficial  boundaries  of  this  region  are  not  well-marked, 
for  it  is  covered  by  the  parts  of  other  regions,  i.  e.,  the  buttocks  behind, 
the  hips  at  the  side,  and  the  perineum  below.  Hence  there  are  but  few 
bony  or  other  landmarks.  Some  of  these  we  have  considered  under  the 
landmarks  of  the  abdomen  (see  p.  268). 

From  the  pubic  spine  to  the  symphysis  we  can  make  out  the  front 
of  the  pelvic  brim,  formed  by  the  pubic  crests,  and  below  this  the  bodies 
of  the  two  pubic  bones,  separated  by  the  symphysis  pubis.  This  part 
is  covered  in  the  female  by  a  thick  pad  of  subcutaneous  fat,  the  mons 
veneris,  which  somewhat  obscures  the  bony  outlines.  The  mons  veneris 
is  separated  from  the  abdomen  above  by  a  transverse  furrow  which 
meets  the  inguinal  furrows  about  their  centre. 

Still  farther  down  in  the  median  line  we  can  feel  the  subpubic  angle 
on  deep  pressure  behind  the  scrotum  in  the  male,  in  the  vestibule  in  the 
female.  Leading  from  this  angle  to  the  ischial  tuberosities  we  can  trace 
the  combined  ramus  of  the  pubis  and  ischium  on  each  side,  which  bound  the 
perineum  laterally  and  lie  nearly  in  the  genitocrural  furrows.  The  latter 
are  the  furrows  between  the  inner  aspect  of  the  thighs  and  the  perineum, 
and  are  continuous  behind  with  the  gluteal  folds.  It  is  near  the  inner  end 
of  the  latter  that  the  ischial  tuberosities  can  be  readily  felt.  In  the  sitting 
posture  these  tuberosities  are  only  separated  from  the  skin  by  the  sub- 
cutaneous fat  and  a  bursa.  This  bursa  is  liable  to  inflammation  in  those 
who  sit  a  great  deal,  like  coachmen,  weavers,  etc.  In  the  standing  pos- 
ture the  tuberosities  are  overlapped  by  the  lower  borders  of  the  gluteus 
maximus  muscles.  The  ischial  tuberosities  form  one  end  of  Nelaton's 
line  (see  p.  486)  and  the  line  connecting  them  with  the  central  point  of 
the  perineum  divides  the  perineum  proper  in  front  from  the  ischiorectal 
fossa  behind. 

In  the  median  line  behind  we  can  feel  the  spinous  process  of  the  fifth 
lumbar  vertebra,  often  indicated  by  a  little  furrow,  and  below  this  those 
of  the  sacral  vertebrae,  of  which  the  third  is  the  most  prominent.  Fol- 
lowing down  in  the  median  line,  in  the  deep  fold  between  the  buttocks, 
we  can  feel  the  tip  of  the  coccyx,  behind  which  (especially  in  women) 
there  is  often  a  more  or  less  marked  dimple  or  depression  of  the  skin 


THE  PELVIS  395 

(Joveola).  Through  the  vagina  or  rectum  can  he  felt  posteriorly  the  front 
of  the  coccyx  and  sacrum,  laterally  the  spines,  the  inner  aspect  of  the 
tuberosities  and  the  bodies  of  the  ischia  and  the  great  sacrosciatic  fora- 
mina, and  anteriorly  the  back  of  the  pubic  bones  and  symphysis  and  the 
obturator  foramina.  With  a  long  finger  or  half  hand,  when  the  patient 
is  anesthetized,  the  sacral  promontory  can  be  felt  above  and  behind,  but 
if  this  can  be  felt  in  an  ordinary  examination  by  a  finger  of  ordinary 
length  the  pelvis  is  considered  abnormal.  The  promontory  can  also  be 
felt  on  deep  pressure  through  a  thin  lax  abdomen,  about  on  a  level  with 
the  anterior  superior  iliac  spines. 

The  Bony  Pelvis. — Although  in  the  bony  state  the  inlet  or  brim  of 
the  pelvis  is  heart-shaped,  with  the  base  behind,  in  the  natural  state  the 
psoas  and  other  muscles  make  it  triangular,  with  the  base  in  front.  The 
outlet  of  the  pelvis  is  composed  of  three  bony  points  separated  by  three 
notches.  The  two  symmetrically  placed  posterior  notches  (sacrosciatic) 
are  bridged  across  by  the  strong  sacrosciatic  ligaments,  which  thus  bound 
the  pelvic  outlet  and  make  it  lozenge-shaped.  The  tuberosities  of  the 
ischium  may  be  quite  close  together  in  the  male.  I  have  seen  this  con- 
dition so  marked  as  to  embarrass  one  in  lateral  lithotomy.  In  the  natural 
position  of  the  pelvis  the  tuberosity  lies  behind  and  below  the  acetabulum, 
and  only  a  trifle  farther  behind  it  than  the  anterior  superior  iliac  spine 
is  in  front  of  it.  The  level  of  the  ischial  spine  lies  1.5  cm.  (f  in.)  above 
the  upper  border  of  the  symphysis. 

The  coccyx  may  be  fractured  or  dislocated  as  a  result  of  falls  or  blows 
or  during  parturition,  especially  in  those  women  in  whom  the  coccyx  is 
much  incurved  as  the  result  of  sedentary  habits  or  horseback  riding. 
The  displacement  of  the  fracture  or  dislocation  may  be  readily  made  out 
by  rectal  examination,  or  by  a  finger  in  the  rectum  and  the  thumb  on  the 
surface.  The  joint  between  the  coccyx  and  the  sacrum  may  also  be 
sprained  or  diseased.  All  these  conditions  are  very  painful,  owing  to  the 
frequent  movement  at  the  seat  of  injury  or  disease,  due  to  the  muscles 
attached  to  the  coccyx  (gluteus  maximus,  coccygeus,  levator,  and  sphinc- 
ter ani).  The  injured  bone  may  project  into  the  rectum  and  be  moved 
in"  defecation  mechanically  as  well  as  by  the  sphincter  and  levator  ani 
mascles.  The  sacrococcygeal  joint  and  the  parts  about  the  bone  are 
supplied  by  the  posterior  divisions  of  the  coccygeal  and  the  second  to 
the  fifth  sacral  nerves  and  the  anterior  divisions  of  the  fifth  sacral  and 
the  coccygeal  nerves,  which  may  be  the  seat  of  a  painful  neuralgia 
coceydynia).  Removal  of  the  coccyx  may  be  called  for  on  account  of 
injury,  joint  disease,  or  neuralgia. 

Sacrococcygeal  Tumors  and  Cysts. — These  are  congenital  in  origin, 
and  I  have  seen  diem  attain  such  a  size  that  the  possessor,  a  man,  wore 
skirts  to  conceal  the  enormous  mass.  They  grow  on  the  posterior  or 
the  anterior  surf  aces  (between  the  bone  and  the  rectum).  They  belong  to 
the  class  of  tumors  known  as  teratoma,  which  includes  tumors  ranging 
from  the  simple  coccygeal  lipomata  and  dermoid  cysts  to  the  more  com- 
piicated  thyroid  dermoids,  etc.,  which  contain  tissues  derived  from  all 
three  germ  layers.    They  are  supposed  to  arise  from  the  embryonic 


396  PELVIS  AND  PERINEUM 

neurenteric  passage,  or  postanal  gut,  many  claim  the  more  complex  tumors 
are  bigerminal  in  origin  and  derived  from  a  parasitic  twin.  The  der- 
moids over  the  back  of  the  sacrum  and  coccyx  may  be  confounded  with 
spina  bifida.  Attached  human  fetuses  are  often  joined  together  at  this 
part  of  the  column,  and  here,  too,  third  limbs  (tripodesia)  and  parasitic 
fetuses  are  found  attached. 

Sacro-iliac  Joint. — Normally  there  is  no  movement  in  this  joint  except, 
as  Farabeuf  has  shown,  a  slight  rotation  on  a  transverse  axis.  Thus  when 
the  thighs  are  flexed  onto  the  abdomen,  the  conjugate  diameter  is  short- 
ened by  the  rotation  upward  of  the  innominate  bones,  the  symphysis 
approaching  the  promontory.  The  sacrosciatic  ligaments  resist  this 
rotation.  The  reverse  movement  occurs  on  hyperextension  of  the  thighs. 
The  difference  between  these  extremes  is  about  1  cm.,  so  that  extension 
may  be  made  use  of  in  obstetrics  to  slightly  increase  the  conjugate  diam- 
eter of  the  brim.  In  general  the  joint  serves  merely  to  break  shocks,  but 
some  movement  is  said  to  occur  when  the  ligaments  are  softened  by 
disease. 

The  joint  may  become  diseased  as  the  result  of  injury,  by  an  extension 
from  spinal  caries,  etc.,  or  spontaneously.  In  the  latter  two  instances  it 
is  usually  tuberculous.  In  disease  of  this  joint  much  pain  is  felt  in  stand- 
ing or  sitting,  as  in  these  positions  the  weight  of  the  body  is  transmitted 
through  it,  and  pain  is  also  felt  in  any  movement  that  involves  the  action 
of  muscles  attached  to  the  ilium.  This  pain,  besides  being  local,  may  also 
be  of  a  peripheral  reflex  character  over  the  sacral  region  (upper  sacral 
nerves),  in  the  buttocks  (superior  gluteal  nerve),  or  even  at  times  in  the 
thigh  and  calf  (lumbosacral  cord).  The  above-named  nerves  supply  the 
joint,  which  sometimes  gets  a  small  twig  from  the  obturator  nerve  which, 
with  the  lumbosacral  cord,  passes  over  the  front  of  the  joint.  The  obtu- 
rator nerve  accounts  for  referred  pain  in  the  knee-  or  hip-joints.  The 
body  is  inclined  to  the  sound  side  to  diminish  the  pressure  on  the  dis- 
eased joint.  Tenderness  may  be  elicited  by  pressing  together  or  sepa- 
rating the  ilia  or  by  direct  pressure  about  the  posterior  superior  iliac 
spine,  which  corresponds  to  the  centre  of  the  joint. 

If  abscess  forms  it  usually  comes  forward  into  the  pelvis,  as  the  anterior 
ligaments  are  much  the  thinner  and  weaker.  Such  an  abscess  may  enter 
the  iliopsoas  sheath,  perforate  the  rectum,  enter  the  ischiorectal  fossa, 
or  follow  the  lumbosacral  cord  and  sciatic  nerve  to  the  back  of  the  thigh, 
or  the  obturator  nerve  to  the  inner  aspect  of  the  thigh.  More  rarely  the 
abscess  may  pass  backward  and  point  behind  the  joint. 

In  spite  of  the  comparative  weakness  of  the  anterior  sacro-iliac  liga- 
ments, above  mentioned,  dislocation  never  occurs  except  in  fracture  of 
the  pelvis,  or  the  rare  luxation  of  the  sacrum  anteriorly.  This  fact  is 
due  to  the  very  strong  posterior  sacro-iliac  ligaments,  which  sling  the 
sacrum  from  the  ilium,  and  not  to  the  wedge  shape  of  the  sacrum,  for,  in 
the  natural  position  of  the  pelvis,  the  base  of  the  wedge  looks  down- 
ward and  forward,  i.  e.,  in  the  direction  in  which  the  weight  of  the  body 
would  naturally  tend  to  displace  it.  The  wedge  shape  would  prevent 
its  being  dislocated  backward,  but  there  is  no  tendency  to  displacement 


THE  PELVIS  397 

in  this  direction.  At  the  same  time,  owing  to  the  irregularities  of  the 
bony  surfaces  and  the  slightly  projecting  lips  of  the  ilia  in  front  and 
below,  the  sacrum  is  more  or  less  wedged  in  between  the  ilia  like  the 
keystone  of  an  arch,  to  the  pillars  of  which,  the  ilia,  it  transmits  the 
weight. 

The  symphysis  pubis  is  nearly  5  cm.  (2  in.)  in  height,  and  its  thickness 
may  reach  nearly  2.5  cm.  (1  in.).  In  symphysiotomy,  proposed  by  Sigault 
in  1768  as  a  substitute  for  Cesarean  section  to  enlarge  the  pelvic  dimen- 
sions in  labor  in  cases  of  contracted  pelvis,  a  separation  at  the  symphysis 
of  6.2  cm.  (2 \  in.)  increases  the  conjugate  diameter  by  only  12  mm.  (^  in.). 
But,  as  the  convexity  of  the  child's  head  may  project  into  the  interval 
between  the  separated  pubic  bones,  another  12  mm.  or  so  may  be  gained 
for  the  passage  of  the  head.  The  innominate  bones  can  be  separated 
at  the  symphysis,  but  a  very  little  distance  without  first  straining  the 
front  of  the  sacro-iliac  joint,  then  tearing  the  anterior  ligaments  and  the 
cartilages  connecting  the  bony  surfaces.  A  separation  of  7  cm.  at  the 
symphysis  is  possible  without  laceration  of  these  ligaments.  In  addition 
to  the  tearing  of  the  anterior  ligaments,  the  periosteum  is  usually  stripped 
up  for  some  distance  on  the  ilium  in  front  of  the  joint.  As  the  axis  of  this 
separation  or  opening  of  the  joint  is  at  the  back  of  the  joint  and  passes 
obliquely  downward  and  inward,  the  strong  posterior  sacro-iliac  liga- 
ments avoid  injury  and  the  pubic  bones  on  being  separated  pass  down- 
ward as  well  as  outward.  In  addition  to  the  laceration  of  the  sacro-iliac 
joints,  the  attachments  of  the  pelvic  viscera  may  be  damaged.  A  slight 
separation  of  the  pubic  bones  due  to  swelling  of  the  fibrocartilage  has 
been  shown  to  occur  toward  the  end  of  gestation,  but  during  parturition 
the  decussating  tendinous  fibers  of  the  abdominal  muscles,  which  cross 
in  front  of  the  joint,  would  tend  to  brace  the  bones  more  tightly  together. 

Reparation  at  the  symphysis  without  fracture  of  the  bones  is  very  rare, 
l)i it  has  occurred  from  severe  external  violence,  and  Malgaigne  has 
reported  three  cases  where  the  violence  was  merely  muscular,  due  to 
jsive  action  of  the  adductors  of  both  sides. 

The  Mechanism  of  the  Pelvis. — The  weight  of  the  body  is  transmitted 
from  the  sacrum  through  the  pelvis  along  two  arches:  one  for  the  standing, 
the  other  for  the  sitting  posture.  The  arch  for  the  standing  posture 
Consists  of  the  sacrum,  the  sacro-iliac  joints,  the  acetabula,  and  the  thick 
ridges  of  bone  along  the  iliopectineal  line  between  the  two  latter  points. 
For  the  silting  pasture  the  arrh,  is  niiich  the  same,  except  that  the  ischial 
tuberosities  an'  substituted  for  the  acetabula.  These  two  arches  have 
been  called  the  femorosacral  ami  the  ischiosacral  respectively.  The  bone 
in  the  line  of  these  two  arches  is  much  thicker  than  elsewhere  in  the 
pelvis.  The  locrum  occupies  'he  position  of  the  keystone  for  both 
arches  (see  above,  p.  396). 

T  i    trengthen  each  arch  its  ends  are  joined  by  a  counferarch,  which 

Completes  a    ring  and  serves  as  a,  tie  to  keep  the  sides  of  the  arch  from 

eitler  separating  or  collapsing.    The  counterarch  or  tic  of  the  femoro- 

.il   arcfa    \-   formed   by  the  bodies  and   horizontal    rami  of  the  pubes, 
that  of  the  i  tchiosacral  a  rch  by  the  combined  rami  of  the  pubefl  .'ind  ischia. 


398  PELVIS  AND  PERINEUM 

Thus  the  ties  of  both  arches  meet  at  the  symphysis,  to  which  is  conveyed 
a  portion  of  the  weight  or  strain.  Hence  the  strain  felt  at  the  sym- 
physis when  increased  weight  is  to  be  borne,  as  in  pregnancy,  abdominal 
tumors,  etc.,  and  hence  the  powerlessness  in  standing  or  sitting  when 
the  symphysis  is  diseased  or  weakened  by  injury  or  an  unhealed  sym- 
physiotomy. 

Pelvic  Deformities. — Pelvic  deformities  are  also  explained,  according 
to  the  mechanism  of  the  pelvis,  by  the  pull  of  muscles  and  the  weight  of 
the  trunk  acting  on  bones  that  have  not  become  properly  ossified  in 
parts,  owing  to  rickets,  or  on  bones  more  uniformly  softened  by  the  much 
rarer  condition,  osteomalacia.  When  the  rickety  child  walks  but  little 
and  sits  most  of  the  time,  as  they  frequently  do,  the  weight  of  the  body 
thrusts  the  sacral  promontory  forward  and  downward,  thus  diminish- 
ing the  conjugate  diameter  of  the  brim.  The  counterpressure  comes 
from  the  ischial  tuberosities  and  is  most  felt  in  the  counterarch,  which  is 
narrowed  and  pushed  forward  at  the  symphysis,  while  the  tuberosities 
may  approach  one  another  and  narrow  the  transverse  diameter  of  the 
outlet,  or  may  diverge,  widening  the  transverse  diameter  and  the  subpubic 
angle.  If  the  rickety  child  is  more  on  its  feet,  lateral  counterpressure 
is  exercised  at  the  acetabula,  and  is  felt  mostly  at  the  weakest  part  of  the 
pelvis,  i.  e.,  the  counterarch.  Thus  while  the  acetabula  approach  one 
another  more  or  less,  the  most  marked  change  is  often  a  beak-like  pro- 
jection of  the  symphysis,  the  pubic  rami  sometimes  running  parallel  with 
one  another  and  close  together,  showing  a  collapse  of  the  counterarch. 
There  are  many  and  diverse  pelvic  deformities  depending  upon  modi- 
fications of  the  pressure  and  counterpressure  and  the  pull  of  the  muscles. 

In  the  softer  condition  due  to  osteomalacia,  which  occurs  only  in  adult 
life,  the  changes  due  to  lateral  pressure  are  most  marked. 

Fractures  of  the  Pelvis. — Though  the  sacro-iliac  joints  and  the  sym- 
physis might  be  thought  to  be  weak  points  of  the  pelvis,  their  connecting 
ligaments  are  so  strong  that  they  rarely  give  way  primarily;  the  bones 
yield  first.  As  has  just  been  said,  the  counterarch  is  the  weakest  point, 
and  it  is  here  that  fracture  commonly  occurs  from  the  most  varied  forms 
of  violence.  Fractures  of  the  pelvic  arch  usually  occur  as  the  result  of 
violent  pressure  on  the  surface  or  of  falls  from  a  height.  Thus  if  the 
force  be  applied  in  the  anteroposterior  direction,  the  weak  counterarch 
yields  to  direct  or  indirect  violence  on  one  or  possibly  both  sides  of  the 
symphysis  through  the  pubes  or  the  rami.  The  force  continuing  tends 
to  separate  the  two  innominate  bones  and  to  cause  a  diastasis  and 
finally  a  dislocation  of  the  sacro-iliac  joints,  as  in  symphysiotomy,  or 
a  fracture  of  the  ilium  external  to  these  joints.  Again,  if  the  force  be 
applied  transversely,  the  pelvis  tends  to  become  flattened  laterally,  but 
the  weaker  counterarch  is  more  flattened,  and  eventually  gives  way  and 
is  fractured  by  indirect  violence.  Should  the  force  continue,  the  two  hip 
bones  are  pressed  toward  each  other  and  the  strain  on  the  sacro-iliac 
joint  falls  upon  its  posterior  part.  Here  the  ligaments  are  so  strong 
that,  instead  of  their  rupture,  portions  of  bone  to  which  they  are  attached, 
especially  the  sacrum,  are  usually  torn  away.     In  falls  on  the  feet  or 


THE  PELVIS  399 

ischial  tuberosities  it  is  again  the  weaker  or  counterarch  which  is  usually 
fractured.  In  falls  from  a  height  or  other  severe  injuries  the  head  of  the 
femur  may  be  driven  through  the  acetabulum,  but  this  is  rare. 

A  separation  of  the  hip  bone  into  its  three  constituent  parts  cannot 
occur  after  about  the  eighteenth  year,  at  which  time  the  three  parts  are 
firmly  united  by  the  ossification  of  the  Y-shaped  cartilage.  Before 
this  occurs  abscess  within  the  capsule  of  the  hip  joint  may  make  its 
way  into  the  pelvis  through  the  cartilage,  but  this  is  not  as  common  an 
occurrence  as  one  would  expect.  Separation  of  the  epiphysis  of  the  iliac 
crest  and  spines  may  result  from  direct  violence  or  even  from  muscular 
action.  Localized  direct  violence  of  sufficient  force  may  fracture  any 
part  of  the  pelvis. 

Apart  from  the  fact  that  the  violence  producing  fractures  of  the  pelvis 
is  usually  severe  and  entails  shock  and  often  other  remote  injuries, 
such  fractures  are  serious  on  account  of  and  in  proportion  to  the  injury 
to  the  pelvic  viscera  from  sharp  fragments  or  loose  pieces  of  bone,  or 
from  crushing  or  tearing.  Thus  the  bladder  and  urethra,  and  in  the 
female  the  vagina,  are  especially  liable  to  be  torn  by  sharp  fragments, 
and  the  urethra  may  be  ruptured  or  compressed,  owing  to  its  close  rela- 
tion to  the  subpubic  arch.  A  vesical  calculus  has  been  reported  having 
for  its  nucleus  a  piece  of  bone  driven  into  the  bladder  in  a  fracture  of  the 
pelvis.  It  is  in  the  double  fractures  of  the  pelvic  arch  that  the  viscera 
are  most  often  wounded.  In  these  double  fractures  the  two  lines  of  frac- 
ture are  most  often  on  one  side  of  the  symphysis,  rarely  on  both;  or  in 
place  of  the  second  fracture  we  may  have  a  diastasis  of  the  symphysis, 
which  usually  occurs,  if  at  all,  in  connection  with  fractures  of  the  pelvic 
arch.  Or  if  the  second  fracture  passes  through  the  ilium,  a  little  external  to 
the  sacro-iliac  joint,  the  large  pelvic  fragment  may  be  displaced  upward 
with  the  attached  femur  and  lead  to  a  mistaken  diagnosis  of  fracture 
of  the  neck  of  the  femur.  But  the  relation  of  the  great  trochanter  to  the 
anterior  iliac  spine  is  unaltered.  The  rectum,  too,  has  been  torn  or 
compressed  in  fractures  of  the  sacrum  or  coccyx.  Information  may 
often  be  gained  for  the  diagnosis  of  fracture  of  the  pelvis  by  rectal  or 
vaginal  examination,  and  blood  in  the  urine  in  such  cases  indicates  an 
injury  to  the  bladder  or  urethra.  The  capsule  of  the  hip  joint  is  almost 
always  external  to  the  line  of  fracture  of  the  pelvic  arch,  and  thus  escapes 
injury. 

In  the  ered  position  the  planeof  the  brim  or  inlet  of  a  normal  pelvis 
makes  an  angle  of  about  60  degrees  with  the  horizon,  which  is  due  to 
the  sacrovertebral  angle  and  the  obliquity  of  the  articulation  of  the  hip 
bones  with  the  Bacrum.  This  anteroposterior  tilting,  which  we  call  the 
obliquity  of  the  pelvis,  varies  in  different  eases,  and  averages  greater  in 
the  female  than  in  the  male.  In  hip  disease,  with  ankylosis  of  the  hip- 
joint  in  the  flexed  position,  the  pelvis,  as  a  whole,  moves  about  the  trans- 
,  paa  ing  through  the  acetabula,  and  its  obliquity  is  increased  on 
iding,  in  order  to  bring  the  ankylosed  limb  into  a  vertical  position. 

To  allow  of  this  increased  obliquity  of  the  pelvis  the  forward  eonvex- 
ilv  of    the    lumbar   vertebra   is   increased  (lordosis)  by  their   extension. 


400 


PELVIS  AND  PERINEUM 


Increased  obliquity  causes  a  protrusion  of  the  belly  and  a  backward 
position  of  the  external  genitals.  The  normal  obliquity  of  the  pelvis  may 
be  shown  by  placing  the  anterior  superior  iliac  spines  and  the  pubic 
spines  in  the  same  vertical  plane,  as  against  the  wall  (H.  v.  Meyer). 

The  inclination  of  the  pelvic  outlet,  or  the  angle  between  the  horizon 
and  the  line  connecting  the  tip  of  the  coccyx  with  the  lower  border  of  the 
symphysis,  averages  from  12  to  15  degrees.  The  axis  of  the  inlet,  or 
the  line  at  right  angles  to  the  centre  of  its  plane,  passes  obliquely  forward 
and  upward,  so  that  if  prolonged  it  would  meet  the  umbilicus  above  and 
the  middle  of  the  coccyx  below.  The  axis  of  the  outlet  prolonged  upward 
touches  the  base  of  the  sacrum,  and  prolonged  downward  is  directed 
slightly  backward,  whereas  the  curved  line  representing  the  axis  of  the 
entire   pelvis,   if  prolonged   downward,   would   curve   forward.     This 

Fig.  135 


FIFTH     LUMBAR 
VERTEBRA 


ANTERIOR  SUPERIOR 
ILIAC    SPINE 
ANTERIOR      INFERIOR 
ILIAC    SPINE 
POU  PART'S 
LIGAMENT 

PUBIC  SPINE 


OBTURATO 
MEMBRANE 


POST. -SUP.   ILIAC 

SPINE 
POST. -INF.   ILIAC 

SPINE 
GREAT    SACRO- 

SCIATIC    FORAMEN 
GREAT    SACRO-SCIATIC 

LIGAMENT 
-SMALL   SACRO-SCIATIC 

LIGAMENT 
SMALL  SACRO-SCIATIC 

FORAMEN 


ISCH.  TUBEROSITY 


Female  pelvis  viewed  from  the  left  side,  showing  the  position  of  its  parts  in  the  erect 
posture.      (Joessel.) 

distinction  is  not  always  understood.  The  axis  of  the  cavity,  nearly 
straight  above,  more  curved  below,  is  parallel  to  the  curve  of  the  sacrum 
and  equidistant  from  all  sides  of  the  pelvis.  The  descent  of  the  fetal 
head  follows  this  curved  line,  turning  as  it  were  around  the  symphysis 
as  an  axis.  As  this  curved  axis,  continued  downward,  passes  near  the 
centre  of  the  vulva,  those  cases  where  the  vulva  is  unusually  far  forward 
are  more  exposed  to  rupture  of  the  perineum  in  delivery.  It  is  also  in 
this  curved  direction  that  instruments  (sounds,  forceps,  etc.)  are  passed 
to  the  pelvic  viscera. 

With  a  normal  inclination  of  the  pelvis,  the  sacral  promontory  lies 
9.5  cm.  (3f-  in.)  above  the  upper  border  of  the  symphysis  and  the  tip  of 
the  coccyx  1.2  to  2.5  cm.  (|  to  1  in.)  above  its  lower  border.  The  long 
axis  of  the  symphysis  forms  an  angle  of  100  degrees  with  the  conjugate 
diameter  of  the  brim,  i.  e.,  the  line  between  the  promontory  or  sacro- 


THE  PELVIS  401 

vertebral  angle  and  the  upper  end  of  the  symphysis.  This  fact  is  of 
importance  in  obstetrics,  as  the  fetal  head  makes  one  of  its  principal 
turns  around  the  symphysis. 

Obstetricians  consider  three  diameters:  ventrodorsal  or  conjugate, 
transverse  and  oblique,  in  three  planes  of  the  pelvis,  that  of  the  brim, 
the  centre  or  largest  part  of  the  cavity,  and  the  outlet.  The  oblique 
diameter  is  between  the  sacro-iliac  joint  and  the  inner  surface  corre- 
sponding to  the  acetabulum  of  the  opposite  side,  measured  at  the.  inlet, 
the  outlet,  and  in  the  cavity.  The  transverse  diameter  at  the  outlet 
is  the  distance  between  the  ischial  tuberosities.  The  measurements  of 
the  diameters  vary  according  to  age,  sex,  and  individuality,  and  especially 
in  the  presence  of  pelvic  deformities.  In  the  female  they  average  as 
follows : 

Anteroposterior.  Transverse.  Oblique. 

Cm.    Inches.  Cm.     Inches.  Cm.      Inches. 

Inlet 11.0        m  13.25     5X  12.5        5 

Cavity 12.7        5  12.5        4%  13.0        5H 

Outlet 11.5        4H  HO        4  i  11.5        4»^ 

If  the  measurements  are  materially  diminished  symmetrically,  as  in 
(•uses  of  "equally  contracted  pelvis,"  in  women  apparently  well  formed, 
or  un.symmetrically  in  rachitic  pelvic  deformities,  normal  labor  may  be 
rendered  difficult  or  impossible.  It  should  be  noted  that  the  pelvis  does 
not  form  a  complete  unyielding  bony  ring  in  any  horizontal  plane,  but 
that  everywhere  a  firm  bony  portion  has  opposite  to  it  soft  and  yielding 
parts. 

The  apparently  greater  width  of  the  female  pelvis,  as  shown  by  the 
hips,  is  due  to  the  greater  amount  of  subcutaneous  fat  and  the  compari- 
son with  the  narrower  waist.  The  distance  between  the  anterior  superior 
spines  averages  G  to  10  mm.  (^  in.)  greater  in  the  female,  that  between  the 
iliac  crests  averages  1  cm.  (f  in.)  greater  in  the  male,  while  Quain  gives 
both  greater  in  the  male.  The  true  pelvis  is  shallower,  broader,  and 
more  capacious  iii  the  female;  the  false  pelvis  is  relatively  narrower  and 
less  deep  in  the  female  (Quain).  In  the  female,  too,  the  symphysis  is 
less  deep  and  both  the  subpubic  arch  and  the  distance  between  the  ischial 
tuberosities  is  much  wider,  all  of  which  are  of  importance  in  the  mechan- 
ism of  labor. 

The  pelvis,  as  a  whole,  may  move  on  three  axes:  a  transverse  (flexion 
and  extension),  an  anteroposterior  (tilting),  or  a  vertical  (rotation). 
These  movements  take  place  in  the  lumbar  spine.  Flexion  and  extension 
are  die  most  important  and  the  most  extensive,  and  decrease  or  increase 
die  obliquity  of  the  pelvis,  respectively.    When  (he  hip  joint  is  fixed 

or  ankvlosed  it  is  tin-  pelvis  (hat  is  flexed  or  extended  on  the  trans- 
verse axis  passing  through  the  acetabula.  It  is  enabled  to  do  this  by 
movements  of  the   lumbar  spine   in   tin-   same  direction    (see  above,   p. 

Normally  the  pelvis  is  on  the  same  level  on  the  two  sides,  so  thai   die 
line  joining  the   two  anterior  superior  iliac  spines   is   horizontal   in   the 
erect  position.     Pathologically  this  line  may  be  oblique,  SO  that  there  is 
26 


402  PELVIS  AND  PERINEUM 

a  lateral  obliquity  or  tilting  of  the  pelvis  on  an  anteroposterior  axis. 
In  such  a  case  one  side  of  the  pelvis  is  raised,  while  there  is  a  lateral  curve 
of  the  lumbar  vertebra?  toward  the  opposite  side  to  enable  the  trunk  to 
be  held  erect.  This  is  often  the  result  of  hip  disease,  where  the  thigh  on 
the  affected  side  may  be  fixed  in  the  ad-  or  abducted  position,  and  the 
pelvis  is  tilted  to  allow  the  limbs  to  hang  vertically  in  standing  or  walking. 
Or  it  may  result  from  a  shortened  limb,  from  fracture  or  any  other  cause, 
and  the  length  of  the  two  limbs  is  made  apparently  and  often,  for  prac- 
tical purposes,  virtually  equal  by  the  tilting  of  the  pelvis  downward  on 
the  side  of  the  shortened  limb. 

These  facts  have  an  important  bearing  on  the  measurements  of  the 
length  of  the  lower  extremities. 

Before  illustrating  the  bearing  of  these  facts  on  such  measurements, 
it  is  well  to  notice  that  the  anterior  superior  iliac  spines,  from  which  we 
take  our  measurements,  lie  lateral  to  the  acetabula.  Hence  we  measure 
the  long  side  of  an  oblique-angled  triangle  of  which  the  short  side  is  the 
line  between  the  iliac  spine  and  the  acetabulum,  and  the  third  side  is  the 
lower  limb  itself.  If  the  two  limbs  are  of  equal  length  and  one  is  fixed  at 
the  hip  in  the  abducted  position,  the  other  limb,  to  be  parallel  with  it,  must 
be  adducted  (Fig.  136,  ACM'  and  A'CM").  By  a  lateral  tilting  of  the 
pelvis  both  limbs  are  made  apparently  straight  and  in  the  long  axis  of  the 
body  (Fig.  137).  The  pelvis  on  the  abducted  side  is  lowered  by  the 
tilting,  hence  its  acetabulum  is  lower  than  that  of  the  opposite  side. 
Therefore  the  limb  on  the  abducted  side  will  appear  longer  (apparent 
lengthening)  than  that  on  the  adducted  side,  which  cannot  touch  the 
ground.  If,  however,  we  measure  the  two  sides,  we  are  surprised  to  find 
that  the  abducted  and  apparently  longer  limb  measures  less  (measured 
shortening)  than  the  other,  while  in  reality  the  two  are  exactly  equal  in 
length. 

The  explanation  is  simple.  As  one  limb  is  gradually  abducted,  the 
triangle,  whose  long  side  we  measure,  approaches  more  nearly  a  right- 
angled  triangle  until  it  becomes  one,  hence  the  length  of  the  long  side  we 
measure  decreases  as  we  abduct,  for,  the  two  sides  remaining  the  same, 
the  long  side  decreases  in  length  as  the  angle  decreases  from  an  oblique 
angle  to  a  right  angle,  and  vice  versa.  As  the  other  limb  is  gradually 
adducted  the  obtuse  angle  in  the  triangle  increases,  so  that  the  long  side 
measures  more  and  more  until  the  side  representing  the  limb  is  in  line 
with  the  short  side  of  the  triangle,  and  then  the  line  we  measure 
coincides  with  two  sides  of  the  triangle,  which,  according  to  a  rule  of 
geometry,  are  always  greater  than  the  third  side  (Fig.  137,  A' CM7). 

Hence  we  see  that  abduction  decreases  measured  lengthening  and  adduc- 
tion increases  it.  Therefore,  in  measurements  to  determine  the  compara- 
tive length  of  the  limbs  it  is  necessary  to  see  that  there  is  neither  abduc- 
tion nor  adduction.  This  we  do  by  seeing  that  there  is  no  tilting  of  the 
pelvis  and  that  the  limbs  are  in  the  long  axis  of  the  body,  or,  in  practice, 
that  the  line  connecting  the  anterior  superior  iliac  spines  (Fig.  136, 
AA1)  is  at  right  angles  to  the  long  axis  of  the  body  (Fig.  136,  VP),  and  that 
the  latter  prolonged  is  equidistant  from  the  malleoli  of  the  two  feet  to 


THE  PELVIS 


403 


which  we  measure  (Fig.  136,  MP-PM).  Or  stretch  a  string  or  bandage 
from  the  umbilicus  to  the  midpoint  between  the  two  ankles  (Fig.  136, 
VP)  and  see  that  this  is  at  right  angles  to  a  line  connecting  the  two 
anterior  superior  iliac  spines  (Fig.  137,  AA'). 

Another  anomaly  is  that  if  one  side  is  actually  a  little  shorter  (actual 
shortening)  and  the  pelvis  is  tilted,  the  short  limb,  if  adducted,  may  appear 
shorter  and  measure  longer  than  the  longer  limb,  or,  if  abducted,  it  may 
appear  longer  and  measure  shorter.  When  the  pelvis  is  tilted  and  the 
limbs  are  in  the  long  axis  of  the  body  the  limb  on  the  lower  side  is  always 


Fig.  136 


Fig.  137 


Diagrams  to  show  the  correct  (Fig.  136)  and  the  incorrect  (Fig.  137)  position  for  measure- 
ment of  the  lower  extremity  and  the  effects  of  ab-  and  adduction  on  the  apparent  and  measured 
length  of  the  limbs.  The  plain  lines  in  Fig.  136  show  the  correct  position  for  measurement;  the 
crossed  lines  represent  the  left-hand  limb  abducted,  the  right  adducted.  This  same  position  is 
shown  in  Fig.  137,  but  the  pelvis  is  tilted  to  bring  the  limbs  in  line  with  the  axis  of  the  body: 
A,  anterior  superior  iliac  spine;  C,  cotyloid  cavity;  V,  umbilicus;  M,  malleolus;  P,  point  equi- 
distant from  the  two  malleoli;  VP,  line  from  this  point  to  the  umbilicus;  AA,  line  connecting 
the  two  iliac  spines;  AM,  the  line  of  measurement;  CM,  the  real  length  of  the  limb;  AC,  the 
line  from  the  iliac  spine  to  the  cotyloid  cavity. 


abducted,  and  vice  versa.  Actual,  measured,  and  apparent  shortening  do 
not  coincide  unless  there  is  do  filling  of  the  pelvis.  If  one  limb  is  a  little 
shorter  as  a  result  of  fracture  of  the  femur,  old  hip  trouble  with  loss  of 
ubstance  of  the  head,  excision  of  hip  joint  or  knee  joint,  etc.,  it  may  be 
made  of  equal  length  with  the  other,  to  all  appearances  and  for  all  practical 
purposes,  by  tilting  the  pelvis  down  on  the  short  side;  and  up  on  the  long 
ride,  and  abducting  if  on  the  former  and  adducting  if  on  the  latter.  The 
ilightly  horter  limb  would  appear  equal,  but  measure  considerably 
shorter,    'rim-;  fracture  of  the  femur  with  2.5  cm.  (I  in.)  or  so  of  shorten- 


404  PELVIS  AND  PERINEUM 

ing  may  be  compensated  for  by  such  a  slight  tilting  of  the  pelvis  that  it  is 
scarcely  noticed  and  produces  no  awkwardness  of  gait.  The  pelvis  may 
also  be  rotated  on  a  vertical  axis  so  that  one  anterior  superior  iliac  spine 
is  in  advance  of  the  other.    This  may  also  occur  in  hip  disease. 

The  Lining  of  the  Pelvis. — Pelvic  Floor  or  Diaphragm. — At  the  sides  of 
the  pelvis  the  ischium,  the  obturator  membrane,  and  the  bony  margins 
bounding  it  are  well  padded  by  the  thick  obturator  internus  muscle.  At 
the  back  of  the  pelvis  is  the  pyriformis  on  either  side,  while  the  outlet  is 
occupied  by  the  coccygeus  behind  and  the  levator  ani  in  front.  These 
latter  two  muscles,  especially  the  levator  ani,  form  the  sagging  floor  or 
diaphragm  of  the  pelvis  and  separate  its  cavity  from  the  perineum  in 
front  and  the  ischiorectal  fossae  behind.  Indeed,  the  pelvis  is  so  well 
padded  that  the  bone  appears  in  but  two  places,  the  pubis  in  front  and 
the  spine  of  the  ischium  laterally. 

The  anterior  border  of  the  levator  ani  passes  backward  and  downward 
along  the  side  of  the  prostate,  and  some  of  its  fibers  unite  beneath  it  with 
those  of  the  opposite  side  at  the  central  tendinous  point  of  the  perineum, 
where  they  blend  with  the  external  sphincter  ani  and  the  transversus 
perinei  muscles.  The  posterior  fibers  of  the  levator  ani  are  attached  to 
the  tip  of  the  coccyx.  The  rectum  in  both  sexes  and  the  vagina  in  the 
female  perforate  in  the  median  line  the  pelvic  floor,  formed  by  the  levator 
ani,  and  at  these  points  the  fibers  of  the  muscle  interlace  with  the  longi- 
tudinal muscle  fibers  of  the  walls  of  those  organs,  more  intimately  with 
those  of  the  rectum.  Elsewhere  in  the  median  line  the  levator  ani  is 
attached  to  the  median  fibrous  raphe,  extending  from  the  coccyx  to  the 
rectum  and  thence  to  the  central  tendinous  point  of  the  perineum. 

Besides  the  openings  for  the  rectum  and  vagina  there  are  several 
small  openings  in  the  pelvic  walls  for  the  passage  of  vessels  and  nerves: 
(1)  through  the  great  sciatic  notch,  above  the  pyriformis,  for  the  superior 
gluteal  vessels  and  nerves;  (2)  through  the  great  sciatic  notch  between 
the  pyriformis  and  the  coccygeus  for  the  internal  pudic  and  sciatic  vessels 
and  nerves  and  the  inferior  gluteal  vessels;  (3)  through  the  obturator 
foramen  above  the  internal  obturator  muscle  for  the  obturator  vessels 
and  nerves.  The  gap  in  the  pelvic  floor  between  the  levator  ani  muscles 
in  front  is  filled  by  the  triangular  ligament,  which  is  pierced  by  the  urethra 
and,  above  it,  by  the  dorsal  vein  of  the  penis,  or  the  corresponding  vein 
in  the  female. 

Pelvic  Herniae. — Through  the  first  two  foramina  above  mentioned,  two 
of  the  forms  of  pelvic  hernise  occur. 

Obturator  hernia  occurs  through  the  obturator  canal,  which  is  directed 
downward,  forward,  and  inward  beneath  the  horizontal  ramus  of  the  pubis 
for  about  2  cm.,  with  a  diameter  of  1  to  l-§-  cm.  Such  a  hernia  pushes  a 
sac  of  pelvic  peritoneum  before  it  and  sometimes  the  obturator  fascia. 
It  comes  to  lie  deeply  beneath  the  pectineus  and  adductor  longus  mus- 
cles, by  separating  which  it  may  be  exposed  through  an  incision  near  the 
inner  border  of  Scarpa's  triangle.  It  is  often  best  to  reach  it  by  abdomi- 
nal incision  above  the  pubes.^|The  obturator  vessels  and  nerves  are  usually 
on  the  outer  side,  or,  next  most  commonly,  the  nerve  may  be  in  front  and 


PLATE  XXXVII 


FIG.  138 


OBTURATOR 
(VESSELS 
AND    NERVE 


WHITE   LINE 


Pelvic  Floor  in  the  Male.     (Testut.) 
The  fascia  is  in  place  on  left  and  is  removed  on  right  side.     The  dotted  line  outlines  the  bony 

outlet  of  the  pelvis. 

FIG.   139 


OBTURATOR 
MEMBRANE 


ISCHIO-CAVERNOSU 
MUSCLE 


ANAL   FASCIA 
IECHIO-RECTAL    FOSSA 

'anterior  EXT'  n- 
sion) 


AMUS   OF  ISCHIUM 


TRIANGULAR     LICA 
MENT     DEEP  LAYER 


TRIANGULAR 
LIGAMENT, 
SUPERFICIAL 
LAYER 
SUPERFICIAL 
PERINEAL 
FASCIA, 
DEEP   LAYER 


Frontal  Section  of  the  Pelvis  through  the  Middle  of  the  Ischio- 
pubic    Rami.     (Testut.) 

Partly  diagrammatic,  to  ihow  the  pelvic  Fascia,      interior    egmeni  oi    the  lection 
viewed  from  behind.     'I  I"-  !■■'  cue  are  in  blue. 


THE  PELVIS  405 

the  artery  behind.  The  proximity  of  the  nerve,  whieh  supplies  the  hip 
and  knee  joints  and  the  adductor  region,  renders  peripheral  pain  from 
pressure  a  conspicuous  symptom,  which  has  misled  surgeons  into  treating 
it  for  some  other  condition.  As  the  hernia  lies  on  the  mesial  side  of  the 
hip  capsule,  pain  on  moving  the  hip  is  often  a  marked  symptom.  Obtura- 
tor herniae  generally  occur  in  advanced  age  and  much  more  commonly 
in  females,  in  whom,  it  is  well  to  note,  the  inner  orifice  of  the  canal  can 
be  examined  through  the  vagina.  The  hernia  is  too  deeply  situated  to  be 
evident  in  Scarpa's  triangle,  and  may  best  be  detected  by  palpation  along 
the  pubic  ramus  and  behind  the  adductor  longus,  while  the  thigh  is  flexed, 
adducted  and  rotated  out,  or  by  vaginal  or  rectal  examination.  Strangu- 
lation is  the  rule. 

Ischiatic  hernia,  escaping  through  the  great  sciatic  foramen,  above 
or  below  the  pyriformis,  lies  beneath  the  gluteus  maximus  muscle.  It 
is  rare. 

Other  rare  forms  of  herniae  occur  through  the  pelvic  floor,  whose 
starting  point  we  know  only  imperfectly.  They  occur  in  adults,  usually 
in  women,  and  to  one  side  of  the  median  line.  The  sac,  covered  by  the 
rectovesical  fascia,  escapes  through  the  fibers  of  the  levator  ani  muscle 
or  between  it  and  the  coccygeus,  to  appear  in  the  posterior  part  of  the 
labium  niajus  {pudendal  hernia),  in  the  perineum  {perineal  hernia),  in 
the  ischiorectal  fossa  {ischiorectal  hernia),  or  in  the  vagina  {vaginal 
hernia ).  A  rare  form  of  hernia,  whose  sac  is  covered  on  one  side  by  the 
rectal  wall,  may  appear  outside  of  or  just  within  the  sphincter  ani  muscle 
{rectal  hernia).  In  perineal  hernia  the  sac  escapes  in  front  of  the  rectum, 
between  it  and  the  vagina  or  prostate,  and  in  pudendal  hernia  it  escapes 
between  the  ischial  ramus  and  the  vagina. 

Pelvic  Fascia  (Fig.  L39). — The  muscles  of  the  walls  and  floor  of 
the  pelvis  are  lined  by  a  fascia,  the  pelvic  fascia.  This  helps  to  form 
a  sheath  for  the  muscles  and  to  separate  more  effectually  the  pelvic 
cavity  from  the  perineum  and  ischiorectal  fossae,  and  it  serves  to 
strengthen  and  support  the  pelvic  viscera  by  its  reflections  onto  them. 
Certain  parts  of  these  reflections  onto  the  viscera  are  called  their  true 
ligaments,  as  in  the  case  of  the  bladder,  etc.  Two  principal  portions  are 
distinguished,  a  parietal  and  ;i  visceral.  |  4 

The  parietal  portion  comprises  the  deep  layer  of  the  triangular  liga- 
ment in  front,  the  fascia  covering  the  pyriformis  behind,  and  the  obtura- 
tor fas-rid  at  the  -ides.  The  latter  lines  the  obturator  internus  and  is 
continuous  with  the  iliac  and  transversalis  fasciae  at  the  pelvic  brim, 
along  which  it  is  attached.  It  is  also  attached  to  the  free  border  of  the 
ischium,  the  falciform  process  of  the  great  sacrosciatic  ligament,  and  the 

inner  lip  of  the  lower  border  of  the  ischiopubic  ramus.     At  the  latter 

attachment  it  i-^  continuous  on  either  side  with  the  deep  layer  of  the 
triangular  ligament.     The  obturator  fascia  forms  a  fibrous  canal  for 

the  internal  pudi<  and  nerves.     Along  a  line  from  the  back  of  the 

pubis  to  the  ischial  spine  the  levator  ani  is  attached  to  this  fascia,  which 

IS  here  thickened  and  hence  appears  white  (the  white  line).     The  obtura- 
tor fa  -ci;i  above  thu  line  ia  sometimes  distinguished  as  "the  pelvic  fascia." 


406  PELVIS  AND  PERINEUM 

From  this  white  line  is  given  off  the  visceral  portion,  or  rectovesical 
fascia,  which  lines  the  upper  or  pelvic  aspect  of  the  levator  ani  and 
coccygeus  muscles  and  is  reflected  onto  the  pelvic  viscera  where  they  pene- 
trate this  muscular  floor,  i.  e.,  rectum  and  vagina,  and  onto  those  immedi- 
ately related  to  the  pelvic  floor,  bladder,  prostate,  seminal  vesicles,  and 
uterus.  According  to  some  the  fascial  layer  which  goes  to  the  viscera  is 
reflected  from  the  visceral  layer  of  pelvic  fascia  along  a  tendinous  arch, 
just  internal  to  the  white  line,  from  the  ischial  spine  to  the  pubopros- 
tatic ligament.  From  the  lower  end  of  the  bladder  it  is  reflected  down 
to  form  the  fibrous  capsule  of  the  prostate,  at  the  apex  of  which  it  is  con- 
tinuous with  the  deep  layer  of  the  triangular  ligament.  It  thus  encloses 
the  vesicoprostatic  plexus  of  veins.  From  either  side  of  the  symphysis  a 
fold  of  this  fascia,  covering  a  small  bundle  of  muscle  tissue  prolonged 
from  the  bladder  (vesicopubic  muscle),  passes  back  to  the  prostate  and 
bladder  as  the  anterior  true  ligaments  of  the  bladder  (puboprostatic 
ligaments).  In  the  depression  between  the  latter  the  pelvic  fascia  is  thin, 
and  through  it  is  seen  a  plexus  of  veins,  connected  with  the  dorsal  vein  of 
the  penis,  which  lies  beneath  the  plexus.  The  fold  from  either  side  of  the 
pelvis  to  the  sides  of  the  bladder,  the  lateral  true  ligaments  of  the  bladder, 
are  scarcely  demonstrable.  Farther  back  the  fascia  passes  across 
between  the  bladder  and  the  rectum,  uniting  yet  separating  them  in  the  tri- 
gonal area  and  investing  the  seminal  vesicles  and  the  vasa  deferentia.  The 
lower  end  of  the  rectum  also  receives  a  thin  prolongation  of  the  fascia. 
The  fascia  where  it  is  reflected  onto  the  viscera  is  easy  to  trace,  but 
becomes  less  and  less  distinct  as  it  is  followed  from  this  point. 

Behind  the  coccygeus  the  rectovesical  and  obturator  fasciae  are  con- 
tinuous with  the  fascia  covering  the  pelvic  aspect  of  the  pyriformis  muscle. 
At  the  anterior  border  of  the  levator  ani  the  rectovesical  fascia  above  it 
joins  the  anal  fascia  beneath  it  and  is  continued  forward  to  the  obturator 
fascia,  or  its  prolongation  the  deep  layer  of  the  triangular  ligament.  It 
is  thus  seen  that  the  pelvic  fasciae  form  a  continuous  lining  of  the  pelvic 
cavity. 

The  reflections  and  attachments  of  the  rectovesical  fascia  exclude  cer- 
tain viscera,  or  parts  of  viscera,  from  the  pelvic  cavity,  i.  e.,  the  prostate, 
seminal  vesicles,  trigone  and  outlet  of  the  bladder,  and  the  lower  4  to  5 
cm.  (1y  to  2  in.)  of  the  rectum.  These  may  be  wounded  without  entering 
the  pelvic  cavity,  and,  provided  their  fascial  sheath  is  intact,  suppuration 
in  them  would  tend  to  spread  toward  the  perineum  and  not  into  the  pelvis. 
On  the  rectum  the  fascia  reaches  some  little  way  below  the  rectovesical 
pouch  of  peritoneum  in  front. 

The  pelvic  vessels  are  on  the  inside  of  the  fascia,  the  nerves  of  the 
sciatic  and  lumbar  plexuses  on  the  outside.  The  vessels,  excepting 
the  obturator,  must  pierce  the  fascia  to  get  out  of,  the  nerves  to  get  into, 
the  pelvic  cavity,  and  through  these  small  openings  inflammation  may 
possibly  spread.  But,  as  a  rule,  suppuration  above  the  fascia  is  limited 
to  the  pelvic  and  abdominal  cavities,  that  below  to  the  perineum  and 
ischiorectal  fossa.  Wounds  of  the  latter  two  regions  that  involve  this 
fascia  have  the  added  danger  of  pelvic  inflammation;  hence  is  seen  the 
surgical  importance  of  the  pelvic  fascia. 


THE  VISCERA  OF  THE  PELVIS  407 

Between  the  peritoneum,  which  lines  part  of  the  pelvic  floor  and 
covers  most  of  the  pelvic  viscera,  and  the  "pelvic"  and  rectovesical 
fasciae  is  a  continuous  layer  of  loose  subperitoneal  connective  tissue, 
in  which  inflammation  may  spread  readily  and  widely  and  lead  to 
suppuration.  This  tissue  is  found  most  abundantly  between  the  ante- 
rior bladder  wall  and  the  pelvis,  about  the  outlet  of  the  bladder,  and, 
in  the  female,  about  the  lower  part  of  the  uterus  and  the  upper  end 
of  the  vagina  and  between  the  folds  of  the  broad  ligament.  Inflam- 
mation and  suppuration  in  this  tissue,  known  as  pelvic  cellulitis,  is 
prevented  from  escaping  through  the  pelvic  floor  by  the  pelvic  fascia. 
Hence,  as  this  tissue  is  continuous  with  the  subperitoneal  tissue  of  the 
iliac  fossa,  the  abscess  usually  passes  up  over  the  pelvic  brim  to  the 
iliac  fossa  and  points  in  the  inguinal  region  (pp.  307-8).  Rarely  it  may 
open  into  one  of  the  pelvic  viscera  or  into  the  peritoneal  cavity.  In 
the  male  it  may  follow  the  vas  deferens  to  the  inguinal  canal  and  scrotum. 
In  women  the  inflammation  and  abscess  are  often  found  within  the  broad 
ligaments  or  beneath  the  peritoneum  lining  Douglas'  pouch,  between 
the  uterus  and  the  rectum.  Clinically  pelvic  cellulitis  is  often  accom- 
panied by  an  inflammation  of  the  pelvic  peritoneum,  pelvic  peritonitis; 
the  latter  may  also  occur  separately. 

In  pelvic  hematocele  the  blood,  if  intraperitoneal,  may  trickle  into 
Douglas'  pouch,  where  it  may  become  enclosed  by  peritoneal  adhe- 
sions; or,  if  subperitoneal,  it  collects  most  often  between  the  layers  of 
the  broad  ligament.  It  often  comes  from  a  ruptured  varicose  ovarian 
vein  or  ectopic  gestation.  Pressure  of  the  mass  on  the  rectum  may  cause 
tenesmus.  These  collections  of  blood  may,  of  course,  become  infected 
and  suppurate,  and  in  such  a  case  can  be  opened  through  the  vagina. 


The  Viscera  of  the  Pelvis. 

The  Rectum. — As  stated  above  (see  Sigmoid  Flexure,  p.  357),  that 
part  of  the  rectum,  formerly  called  the  first  portion,  which  is  provided 
with  a  mesentery  and  extends  from  the  left  sacro-iliac  joint,  at  the 
pelvic  brim,  to  the  middle  of  the  third  sacral  vertebra,  is  now  considered 
as  a  portion  of  the  sigmoid  loop,  with  which  it  is  continuous.  Between 
the  layers  of  the  mesentery  of  this  portion  of  the  sigmoid  run  the  in- 
ferior mesenteric  vessels,  which  divide,  where  the  mesentery  ends,  into 
the  two  sets  of  bilateral  superior  hemorrhoidal  vessels. 

TIm-  rectum  thus  limited  is  more  entitled  to  its  Dame,  rectum  (straight), 
as  it  is  not  curved  laterally,  only  anteroposteriorly.  Of  the  two  parts 
into  which  it  is  naturally  divided,  the  upper  or  i><ioic  portion,  about 
12.5  'in.  (5  in.)  Ion-:,  follows  the  curve  of  the  sacrum  and  coccyx,  upon 
which  it  lies;  the  lower  or  anal  portion  bends  backward  and  downward 
just  below  the  tip  of  the  coccyx.  It  is  important  to  bear  in  mind  the 
direction  of  the  two  curves  in  examining  or  passing  instruments  into  the 
rectum.  The  axis  of  the  ami/,  canal,  if  continued,  meets  the  prostate 
near   its   apex  or  the  rectovaginal   septum.     Hence,   in    introducing  a 


408  PELVIS  AND  PERINEUM 

bougie,  the  nozzle  of  a  syringe,  a  speculum,  etc.,  the  instrument  should 
first  follow  the  axis  of  the  anal  canal  for  2.5  to  3.5  cm.  (1  to  1-|  in.) 
upward  and  forward,  and  then  be  tilted  so  that  its  upper  end  is  directed 
upward  and  backward  in  the  curve  of  the  upper  part. 

The  dividing  line  between  these  two  parts  corresponds  about  to  the 
point  where  the  rectum  pierces  the  pelvic  floor.  The  anal  canal  is 
therefore  entirely  extrapelvic.  In  infants  the  lower  end  of  the  large 
gut  is  straighter  and  more  or  less  vertical,  and  the  upper  part  of  what  was 
formerly  called  the  first  portion  of  the  rectum  is  in  the  abdominal  cavity. 
On  account  of  its  more  vertical  position  in  childhood,  together  with 
its  loose  connections,  the  small  size  of  the  prostate  and  the  liability  to 
such  exciting  causes  as  worms  and  rectal  polypi,  prolapsus  ani  is  espe- 
cially common  at  this  age. 

The  Pelvic  Portion,  or  Rectum  Proper. — Above  the  anal  canal  the  rectum 
is  dilated  into  a  large  ampulla  extending  forward  to  the  apex  of  the 
prostate,  and  backward  to  the  coccyx.  This  part  is  very  distensible, 
and  in  cases  of  fecal  accumulation  may  be  enormously  distended. 
Curious  foreign  bodies  of  large  size  have  been  found  in  this  ampulla, 
such  as,  for  instance,  a  bottle  (Desormeaux),  a  glass  tumbler,  and  an  iron 
match  box.  When  the  rectum  is  distended  in  the  male,  the  bladder  is 
raised  and  pushed  forward  and  the  rectovesical  pouch  of  peritoneum 
is  elevated.  Advantage  has  been  taken  of  this  fact  in  suprapubic  cystot- 
omy by  distending  the  rectum  by  a  rubber  bag,  inflated  with  air  or  water, 
to  help  raise  the  bladder  above  the  symphysis. 

It  is  large  enough  to  contain  the  entire  hand,  which  may  be  introduced, 
if  not  over  eight  inches  in  diameter,'  after  a  gradual  dilatation  of  the 
sphincters  under  anesthesia.  By  a  semirotatory  movement  it  can  be 
insinuated  into  the  lower  end  of  the  sigmoid  loop.  It  is  said  that  a 
large  part  of  the  abdomen  may  be  thus  examined,  even  as  far  as  the 
kidneys,  owing  to  the  mobility  of  the  sigmoid.  Yet  the  practice  is  dan- 
gerous, as  the  bowel  may  be  torn,  especially  that  part  covered  by  perito- 
neum, and  the  sphincter  may  be  permanently  paralyzed.  Moreover,  the 
practical  results  are  unsatisfactory,  owing  to  the  cramping  of  the  hand. 
By  means  of  a  wooden  lever,  invented  by  Mr.  Davy,  introduced  into  the 
rectum,  the  common  iliac  vessels  have  been  compressed  against  the 
pelvic  brim  to  arrest  hemorrhage  in  amputation  at  the  hip  joint. 

Attachments. — Although  the  rectum,  in  passing  through  the  pelvic 
floor,  receives  an  investment  from  the  rectovesical  fascia,  this  investment 
is  not  so  firm  but  that  in  rare  cases  all  the  walls  of  the  gut  are  prolapsed  at 
the  anus.  This  mobility  of  the  rectum  is  of  use  in  excision  of  its  lower 
part,  for  it  allows  the  upper  part  to  be  drawn  down  so  as  to  be  sutured 
to  the  skin  or  to  the  edges  of  a  healthy  anal  segment.  In  order  to  free  it 
for  removal  the  levator  ani  muscle,  some  of  whose  fibers  are  prolonged 
into  and  support  the  bowel,  is  divided,  and  the  fasciae  forming  the 
sheath  of  the  muscle  are  separated  from  the  rectum.  To  allow  the  upper 
part  to  be  pulled  down  the  peritoneal  attachment  must  be  loosened.  This 
may  be  done  by  carefully  stripping  up  the  peritoneum  from  off  the 
front  and  sides  of  the  rectum  and  bluntly  loosening  the  mesentery 


THE  VISCERA  OF  THE  PELVIS  409 

behind.  If  it  is  necessary  to  pull  down  more,  we  must  open  the  peri- 
toneum, dividing  it  close  to  the  rectum  in  front  and  at  the  sides,  to  avoid 
wounding  the  ureter,  and  as  near  as  possible  to  the  sacrum  behind 
in  dividing  the  mesosigmoid,  to  remove  all  the  sacral  glands  and  to 
avoid  the  bloodvessels,  which  run  superficial  to  the  muscle  layers,  for 
injury  to  these  vessels  means  gangrene  of  the  upper  segment. 

The  rectum  is  loosely  attached  by  loose  connective  tissue  to  the  lower 
half  of  the  sacrum  and  the  coccyx,  while  in  front  it  is  more  closely 
attached  to  the  back  of  the  prostate  and  bladder  by  firmer  connective 
tissue,  the  prostatoperitoneal  aponeurosis,  connected  with  the  recto- 
vesical fascia.  This  aponeurosis,  however,  allows  the  separation  of  the 
rectum  from  the  prostate  and  bladder,  and,  if  traced  upward,  is  found  to 
be  attached  to  the  bottom  of  the  rectovesical  pouch  of  the  peritoneum. 
In  the  female  the  rectum  is  attached  to  the  vagina  in  front  by  a  con- 
siderable amount  of  looser  connective  tissue. 

Relations. — The  relations  of  the  rectum  have  a  twofold  importance, 
first  in  diseases  of  or  operations  on  the  rectum;  second,  because  rectal 
examination  is  of  the  greatest  importance  in  determining  the  condition 
of  the  organs  in  relation  to  it. 

Relations  to  the  Peritoneum. — As  the  rectum  commences  opposite  the 
third  sacral  vertebra,  there  is  no  mesorectum,  but  the  peritoneum,  at  first 
covering  the  front  and  sides  of  the  bowel,  is  reflected  from  the  sides 
along  an  oblique  line  descending  from  behind  forward.  It  is  finally 
reflected  from  the  front  of  the  rectum  onto  the  bladder  in  the  male,  and 
onto  the  vagina,  cervix,  and  uterus  in  the  female,  forming  the  rectovesical 
and  the  rectovaginal  pouch  (Douglas'  pouch)  respectively.  The  dis- 
tance of  the  rectovesical  pouches  from  the  anal  orifice  is  of  importance  in 
rectal  operations,  and  measures  about  7  cm.  (2f  in.)  when  the  bladder 
is  empty,  and  considerably  more  when  it  is  full.  The  distance  of  the 
similar  pouch  in  the  female  (Douglas*  pouch)  from  the  anus  is  somewhat 
less. 

In  complete  prolapse  of  the  rectum  of  large  size  this  peritoneal  pouch 
may  be  protruded  and  may  contain  coils  of  intestine,  which  occupy  it 
in  the  normal  condition.  On  the  posterior  rectal  wall  the  peritoneum 
does  not  come  within  12.5  cm.  (5  in.)  of  the  anus.  Thus  ulcers  and  car- 
cinomata  situated  anteriorly  are  more  likely  to  invade  or  ulcerate  into 
the  peritoneal  cavity,  and  in  excisions  of  the  rectum  more  of  the  bowel 
may  be  readily  excised  posteriorly  than  anteriorly.  But,  as  we  have 
seen,  in  the  absence  of  adhesions  we  may  detach  the  rectum  from  the 
peritoneum  and  draw  it  down  as  far  as  the  commencement  of  the  mesen- 
tery, where  the  peritoneum  encloses  the  bowel.  Above  this  point  the 
bowel  may  be  freed  by  dividing  the  peritoneum. 

By  rectal  examination  in  the  female  we  can  feel  anything  abnormal, 
like  ;i  prolapsed  ovary  or  a  retroflexed  or  retroverted  uterus,  occupying 
Douglas'  pouch,  or,  in  the  absence  of  these,  we  can  feel  the  uterus  in 
front  and  die  ovaries  al  tli«'  sides,  if  the  latter  are  enlarged  <>r  displaced. 

Tin-  retroflexed  or  relro  verted   uterus  may  SO  press  upon  the  rectum  as 

to  favor  constipation,  cause  tenesmus,  and  sel  up  inflammatory  or  con- 


410  PELVIS  AND  PERINEUM 

gestive  conditions  in  the  rectum  and  an  adhesion  of  the  opposed  peri- 
toneal surfaces  of  the  pouch.  The  close  relation  of  the  vagina  and 
the  anterior  rectal  wall  accounts  for  the  occurrence  of  tears  into  the  rec- 
tum at  childbirth.  The  fetal  head  has  occasionally  been  forced  through 
the  thin  rectovaginal  wall  and  delivered  per  rectum. 

Below  the  rectovesical  pouch  in  the  male  we  can  feel  the  bladder, 
corresponding  to  the  trigone,  judge  of  its  distention,  and  occasionally 
feel  a  calculus  when  present  in  the  bladder.  Through  the  triangular 
area  of  the  bladder  in  contact  with  the  rectum,  and  below  the  peritoneal 
pouch,  the  distended  bladder  was  formerly  punctured  by  a  trocar  almost 
painlessly,  but,  owing  to  the  danger  of  infection,  this  method  has  been 
superseded  by  the  suprapubic  puncture.  Bounding  the  two  sides  of 
the  triangular  area  are  the  seminal  vesicles,  with  the  vasa  deferentia  in- 
ternal to  them.  These  can  be  readily  felt  when  diseased  (tuberculous) 
or  distended,  not  so  readily  when  normal.  In  violent  attempts  at  defe- 
cation they  may  be  pressed  upon  by  the  fecal  masses  and  partly  emptied, 
producing  a  mechanical  form  of  spermatorrhea.  Massage  of  the  seminal 
vesicles  as  a  therapeutic  measure  has  been  practised  through  the  rectum. 
A  stone  impacted  in  the  lower  end  of  the  ureter  may  possibly  be  felt 
through  the  rectum. 

Below  the  palpable  area  of  the  bladder  and  the  seminal  vesicles  we  readily 
feel  the  'posterior  surface  of  the  prostate,  whose  apex,  3  to  3.7  cm.  (1£ 
to  1+  in.)  from  the  anal  orifice,  is  in  front  of  the  lower  end  of  the  ampulla. 
By  rectal  palpation  we  can  feel  the  changes  of  size,  shape,  consistency, 
and  sensitiveness  in  hypertrophy,  inflammation,  and  abscess  of  the  pros- 
tate. The  enlarged  prostate  naturally  projects  into  the  rectum,  and  when 
of  very  large  size  may  even  cause  obstruction  to  the  passage  of  feces. 
We  can  therefore  readily  appreciate  why  defecation  is  painful  in  pros- 
tatitis, etc.  At  this  part,  too,  a  prostatic  abscess  may  open  into  the  rectum, 
and  such  an  opening  may  result  in  a  urethrorectal  fistula. 

Below  and  in  front  of  the  apex  of  the  prostate  can  be  felt  the  mem- 
branous urethra,  especially  when  occupied  by  a  sound.  The  forefinger 
in  the  rectum,  with  its  tip  at  the  apex  of  the  prostate,  is  used  as  a  guide 
in  Cock's  operation  (perineal  section),  and  is  useful  in  many  perineal 
operations  on  the  urethra,  prostate,  etc.,  and  even  in  passing  a  urethral 
instrument  in  difficult  cases. 

The  bony  points  palpable  by  rectal  examination  have  been  mentioned 
(p.  395).  Their  palpation  is  of  use  in  determining  the  presence  of  any 
fracture,  disease,  or  newgrowth  connected  with  them.  It  is  well  to 
remember,  in  examining  for  suspected  lesions  high  up  in  the  rectum, 
that  by  having  the  patient  strain,  as  at  stool,  especially  in  the  standing 
position,  2.5  to  5  cm.  (1  to  2  in.)  more  of  the  rectum  can  be  palpated 
than  otherwise. 

The  rectum  is  rwt  properly  a  reservoir  for  feces,  and  in  the  healthy 
condition  the  presence  of  the  latter  stimulate  it  to  contract.  In  some 
cases,  especially  those  subject  to  habitual  constipation,  it  may  contain 
a  large  amount  of  feces,  as  often  made  out  by  digital  examination,  the 
nerves  and  muscles  having  become  degenerate  and  ceasing  to  act. 


PLATE  XXXVIII 


FIG.    140 


LEFT    COMMON 


Sagittal  Section  of  the  Lower  Part  of  a  Male  Trunk,  the    Right 
Segment.     (  Gerrish,  after  Testut. ) 


THE  VISCERA   OF  THE  PELVIS  411 

The  anal  canal  or  terminal  portion,  20  to  35  cm.  (A  to  If  in.)  long,  is 
the  narrowest  part  of  the  large  intestine,  although  very  dilatable.  It  is 
limited  by  the  true  skin  below,  the  columnar  epithelium  above.  Its 
lining  consists  of  a  mucocutaneous  tissue  which  shows  a  gradual  trans- 
formation from  the  true  skin  below  to  the  typical  mucous  membrane 
above.  The  upper  limit  is  the  anorectal  line  of  Testut  or  the  free 
borders  of  the  valves  of  Morgagni.  About  4  to  5  mm.  below  the  above 
line  is  an  indistinct  line,  Hilton's  white  line,  usually  to  be  seen  in  the 
living,  not  on  the  dead.  Even  when  not  visible  it  can  be  felt  as  a  depres- 
sion, and  hence  is  sometimes  called  the  anorectal  groove.  It  marks 
the  division  between  the  internal  and  external  sphincters.  The  anal 
canal  is  quite  distinct  in  its  surgical  relations  from  the  rectum.  The 
levator  ani  and  its  enclosing  fasciae  are  attached  to  and  support  its  sides, 
which  are  in  relation  to  the  ischiorectal  fossae.  In  front  lies  the  perineal 
body  in  the  female,  separating  it  from  the  lower  end  of  the  vagina,  and 
the  perineum  in  the  male,  separating  it  from  the  urethra. 

In  the  male  the  anal  canal  forms  the  posterior  wall  of  a  triangle  (uro- 
genital), of  which  the  surface  of  the  perineum  forms  the  base  and  the 
membranous  portion  of  the  urethra,  where  it  adjoins  the  rectum,  the 
apex.  Through  this  triangle  are  made  the  various  perineal  incisions  by 
which  the  bladder  or  posterior  urethra,  and  sometimes  the  prostate  and 
seminal  vesicles,  are  reached. 

Structure  of  the  Rectum. — The  longitudinal  muscle  fibers  are  more 
uniformly  spread  out  than  in  the  rest  of  the  large  intestine,  although, 
according  to  some,  the  three  bands  are  continued  as  two  bands,  one  in 
front  and  one  behind,  which  broaden  as  they  descend.  The  circular 
fibers  are  abruptly  thickened  (to  3  or  4  mm.)  in  the  upper  half  of  the 
anal  canal  to  form  the  internal  sphincter.  The  external  sphincter, 
surrounding  the  anal  orifice  and  the  lower  part  of  the  anal  canal,  below 
the  anorectal  groove,  is  a  striped  or  voluntary  muscle. 

The  looseness  of  the  submucous  tissue  is  such  as  to  allow  the  mucous 
membrane  to  be  protruded  or  prolapsed  at  the  anus  on  prolonged  strain- 
ing at  stool  or  micturition.  The  greater  looseness  of  this  tissue  in 
infants  and  children,  the  less  support  given  by  the  fascial  reflections 
from  other  organs,  and  by  the  undeveloped  prostate  or  uterus,  and  the 
frequency  of  straining  attending  phimosis,  constipation,  or  the  irrita- 
tion of  worms  and  polypi,  makes  this  accident  especially  frequent  in 
early  life.  It  may  also  be  due  to  the  relaxation  of  the  parts  attending 
persistent  diarrhea.  In  adults  it  occurs  mostly  in  old  age  when  the 
muscular  tone  is  weakened.  When  small  it  involves  only  the  mucous 
membrane  and  tends  to  re-ascend,  but  may  be  held  down  by  an  irritated 
sphincter.  When  large  all  the  coats  of  the  bowel  are  apt  to  be  involved 
and  tin-  rectovesical  peritoneal  pouch,  and  even  coils  of  intestine,  may 
be  contained  in  the  prolapse.  The  anal  portion  is  rarely  involved  in 
a  prolapse,  as  it  is  held  so  firmly  by  the  levator  ani  muscle. 

Certain  obliquely  transv<  centic  folds  of  mucous  membrane, 

"Houston's  folds"  or  "valves,"  not  effaced  but  made  more  prominent 
by  the  distention  of  die  rectum,  are  of  importance,  for  they  may  impede 


412 


PELVIS  AND  PERINEUM 


the  passage  of  a  bougie  or  a  rectal  tube,  especially  if  the  rectum  is  empty. 
Hence  in  giving  a  high  enema  first  fill  the  rectum  with  fluid,  and  then 


Fig.  141 


Tunica  muscularis 
(stratum  circulare) 

-7M.  levator  ani 


-Tunica  mucosa 

Tunica  muscularis 
""(stratum  longitudinale 

Sinus  rectalis 


Annulus 
haemorrhoidalis 


Limit  of  hairs 

-  and  sebaceous 

glands 

\M.  sphincter 

ani  internus 

*  Tunica  muscularis 

(stratum 

longitudinale) 

M.  sphincter 

ani  extermis 


v  Adipose  tissue 


x  Cutis 

Section  through  lower  end  of  rectal  wall,  showing  the  relation  of  the  external  and  internal 
sphincters  and  the  extent  of  the  mucous  and  cutaneous  linings.  The  sinus  rectalis  is  the  so- 
called  sinus  of  Morgagni.      (Spalteholz.) 

Fig.  144 


Plaster  cast  of  the  rectum. 


these  folds  will  not  impede  the  passage  of  the  tube.     Three  such  folds 
are  usually  present.     One,  the  largest,  on  the  right  and  anterior  aspect, 


PLATE  XXXIX 


Figs.  142  and  143.  -  Houston's   Folds  seen  through  Speculum, 
with   Rectum   Distended. 


THE   VISCERA  OF  THE  PELVIS  413 

is  just  below  the  rectovesical  pouch  of  peritoneum,  or  about  7.5  cm. 
(3  in.)  from  the  anal  orifice,  and  projects  1  to  3  cm.  into  the  lumen  of 
the  gut,  extending  around  half  of  its  circumference  or  more.  The  other 
two  are  upon  the  left  posterior  quadrant,  above  and  below  the  former, 
and  the  three  are  so  arranged  as  to  form  a  kind  of  spiral  valve.  They 
contain  all  the  coats  of  the  rectum  except  perhaps  the  longitudinal 
fibers,  and  in  casts  of  the  rectum  appear  as  constrictions  dividing  the 
gut  into  sacculi  (Fig.  144).  The  circular  fibers  are  aggregated  at  the  base 
of  these  valves  and  spread  out  in  a  fan-shaped  way  beyond  them,  not  form- 
ing a  complete  sphincter,  although  the  name  of  third  or  upper  sphincter 
has  been  applied  to  one  or  another  of  them,  usually  the  upper.  This 
term  has  also  been  applied  (O'Beirne)  to  a  well-developed  fold  or  valve  at 
the  junction  with  the  sigmoid,  opposite  the  third  sacral  vertebra.  It  is 
situated  more  or  less  anteriorly,  contains  the  same  aggregation  of  circu- 
lar fibers,  and  more  nearly  occludes  the  caliber  of  the  gut  than  the  others 
(Tuttle). 

Commencing  at  the  upper  end  of  the  anal  canal  are  five  to  twelve 
longitudinal  folds  of  mucous  and  submucous  tissue  extending  up  for 
1  to  2  cm.  on  the  rectal  mucosa.  Between  the  lower  ends  of  these 
columns  are  semilunar  folds  or  valves  whose  upturned  concavities  form 
little  sinuses  or  pockets.  These  are  the  columns,  valves,  and  sinuses  of 
Morgagni.  Upon  these  columns  are  to  be  seen  little  protrusions,  due 
to  sac-like  dilatations  of  the  hemorrhoidal  veins  (Duret).  The  upper 
border  of  the  folds  or  valves  marks  the  change  from  mucocutaneous 
tissue  to  the  columnar  epithelium  of  the  rectum,  and  represents  the 
boundary  between  the  anal  canal  and  the  rectum  (anorectal  line). 

The  mucous  membrane  is  liable  to  dysenteric  inflammation  and  ulcera- 
tion, and  the  cicatrization  of  the  ulcers  may  produce  stricture.  The 
liability  to  ulceration  is  greater  the  nearer  we  approach  the  anal  canal. 
As  the  epithelium  of  the  anus  and  anal  canal  is  squamous  or  stratified 
polyhedral,  and  that  of  the  rectum  is  columnar,  an  epithelial  neoplasm 
of  the  former  is  an  epithelioma  (squamous-celled  carcinoma),  and  of  the 
latter  a  carcinoma  or  columnar  epithelioma. 

Vessels.  —The  arteries  of  the  rectum  are  from  three  principal  sources: 
the  inferior  mesenteric,  the  internal  iliac,  and  the  internal  pudic.  The 
middle  sacral  also  supplies  some  blood  to  the  rectum.  The  branches 
of  the  two  lateral  trunks  of  the  superior  hemorrhoidal  pierce  the  muscular 
wall  about  11  cm.  (4§  in.)  from  the  anus  to  form  a  longitudinal  network 
in  the  submucous  tissue.  Hence  incisions  here  should  be  lengthwise 
to  avoid  profuse  bleeding.  The  arteries  communicate  freely  in  a 
plexiform    maimer   near  the   nuns    and    more    or    less  so    above.     The 

veins  have  (he  same  plexiform  arrangement  in  the  submucous  tissue  of 
the  lower  rectum  and  take  the  same  course.  The  blood  of  the  rectum 
proper  is  returned  by  the  superior  hemorrhoidal  to  the  inferior  mesenteric 
vein.  Tin-  middle  and  inferior  hemorrhoidal  veins  return  the  blood 
from  the  outer  surface  of  the  rectum  and  the  anal  canal  t<»  tin-  vena  cava. 
The  anorectal  line  marks  the  boundary  between  the  internal  (superior) 
hemorrhoidal  plexus  above  and  the  external  or  inferior  plexus  below. 


414  PELVIS  AND  PERINEUM 

The  two  systems  are  connected  by  anastomoses  which  in  early  life  are 
very  narrow.  Hence  congestion  of  the  so-called  hemorrhoidal  veins 
of  the  rectum  is  apt  to  follow  physiological  or  pathological  portal 
congestion  as  well  as  venous  congestion  due  to  diseases  of  the  heart, 
lungs,  etc. 

In  addition  to  these  causes,  the  tendency  to  varicosities  of  the  hemor- 
rhoidal veins,  hemorrhoids  or  piles,  is  in  part  due  to  their  dependent  posi- 
tion, the  lack  of  valves  and  any  muscular  and  fascial  support,  and  the 
pressure  of  fecal  masses,  etc.  It  may  also  be  noted  that  the  tributaries 
of  the  superior  hemorrhoidal  veins  are  liable  to  intermittent  constriction 
where  they  pass  through  the  muscular  wall  of  the  rectum,  about  7.5 
to  11  cm.  above  the  anus.  Hemorrhoids  may  also  be  symptomatic 
of  pregnancy,  ovarian  or  abdominal  tumors,  stricture  of  the  rectum, 
prostatic  enlargement,  etc.,  as  all  of  these  conditions  may  obstruct 
the  return  of  venous  blood.  Chronic  constipation  is  a  most  prolific 
cause  of  hemorrhoids,  pressing  on  the  veins,  irritating  the  rectum  and 
causing  straining  at  stool.  These  hemorrhoidal  veins  also  communicate 
with  those  of  the  prostate  and  bladder. 

Hemorrhoids  usually  commence  close  to  the  point  where  the  superior 
and  inferior  sets  of  veins  anastomose  at  the  anorectal  line.  Both  sets 
of  veins  are  usually  simultaneously  involved,  but  when  the  internal  or 
external  set  is  exclusively  or  predominantly  involved  the  varicose  enlarge- 
ment is  called  an  internal  or  external  hemorrhoid  respectively.  A  series 
of  such  swellings  often  surrounds  the  outlet  of  the  bowel.  Piles  are 
usually  confined  to  the  submucous  or  subcutaneous  tissues,  so  that  they 
are  covered  only  by  the  mucous  membrane  (internal  piles)  or  skin  (external 
piles).  The  mucous  membrane  or  the  skin  on  the  surface  of  the  swelling, 
due  to  the  dilated  and  sometimes  thrombosed  veins,  is  chronically  in- 
flamed. The  mucous  membrane  may  be  thickened,  thinned,  or  ulcer- 
ated, in  the  latter  case  leading  to  "bleeding  piles;"  the  skin  is  usually 
thickened,  and  develops  into  a  flabby  tab  when  acute  inflammation  is 
absent. 

It  should  be  borne  in  mind  that  the  lower  rectum  thus  furnishes  an 
important  anastomosis  between  the  portal  and  caval  veins.  Infection 
or  metastasis  spreading  by  vascular  channels  from  the  rectum  usually 
travels  by  the  portal  system  to  the  liver. 

The  Nerve  Supply. — The  nerve  supply  of  the  rectum  is  from  the 
inferior  mesenteric  and  hypogastric  sympathetic  plexuses.  The  anus 
is  supplied  by  the  internal  pudic  nerve  and  the  fourth  sacral  nerve, 
which  accounts  for  the  great  pain  and  the  wide  distribution  of  reflex 
pain  in  anal  fissure,  inflamed  hemorrhoids,  etc.,  and  for  the  paralysis, 
with  incontinence  of  feces,  that  follows  spinal  injuries  or  diseases  in  the 
lumbar  region  or  above.  It  is  also  mainly  responsible  for  the  close 
nervous  association  between  the  anus  and  the  outlet  of  the  bladder, 
which  is  supplied  by  the  same  nerves,  so  that  on  the  one  hand  painful 
affections  of  the  former  may  cause  a  frequent  desire  to  urinate,  and  opera- 
tions on  the  anus  are  especially  apt  to  be  followed  by  temporary  retention 
of  urine  (vesical  spasm);  and  on  the  other  hand  lesions  of  the  outlet 


THE  VISCERA  OF  THE  PELVIS 


415 


of  the  bladder  are  often  associated  with  rectal  tenesmus.  The  upper  part 
of  the  rectum  is  but  little  sensitive,  as  illustrated  by  the  comparative 
painlessness  of  newgrowths,  fecal  accumulations,  and  the  passage  of  in- 
struments high  up  in  the  rectum.  On  the  other  hand,  the  anal  canal 
is  extremely  sensitive. 


Fig.  145 


MTJCOUS   MEMBRANE 


RECTAL  VALVES 


MUSCULAR   COAT 


HEMORRHOIDAL  PLEXUS 
MUSCULAR   COAT 


SPHI NCTER   AN 
INTERNUS 


SPHINCTER   AN  I  -'w5^«' 
EXTERNUS  y&V/ 


^LYMPHATIC   NODULE 


COLUMNS   OF   MORGAGNI 


pnllg^CRYPTS  OF  MORGAGNI 


s^M*         WHITE    LINE   OF   HILTON 


Longitudinal  section  through  rectum,  showing  the  interior.      (Spalteholz.) 

The  Lymphatics. — The  lymphatics  of  the  rectum  and  the  anal  mucous 
membrane  enter  the  sacral  nodes  in  the  mesosigmoid;  those  of  the  skin 
about  the  anna  enter  (he  supero-internal  group  of  the  inguinal  nodes. 
Thus  the  anus  has  a  blood,  nerve,  and  lymphatic  supply  independent  of 
that  of  the  rectum. 

The  Anus.  Hie  anus  is  an  oval,  not  a  circular,  orifice  at  the  lower  end 
of  the  anal  portion  of  the  rectum.  Hence  specula,  etc.,  should  be  intro- 
duced with  the  long  diameter  anteropostenorly  in  the  long  axis  of  the 
anus.  The  anus  lies  in  the  median  line  :>..r>  cm.  Ml  in.)  in  front  of  the 
t,  jui  behind  the  middle  of  a  line  between  the  two  ischial  tuberos- 


416  PELVIS  AND  PERINEUM 

ities  and  only  slightly  farther  from  the  lower  border  of  the  symphysis 
than  from  the  tuberosities.  In  health  it  is  tightly  closed,  and  radiating 
from  its  margins  there  are  numerous  puckerings  or  small  folds  of  skin, 
between  which  fissures  or  ulcers  of  the  anus  form  and  are  often  hidden. 
The  painfulness  of  this  affection  is  due  to  the  reflex  spasm  of  the  sphincter, 
compressing  the  exposed  nerve  fibers  at  the  base  of  the  fissure  or  ulcer, 
which  also  prevents  their  healing.  Hence  dilatation  of  the  sphincter, 
thereby  temporarily  paralyzing  it  and  tearing  the  base  of  the  fissure, 
gives  relief  and  affords  the  fissure  a  chance  to  heal.  Incision  of  the  base 
of  the  ulcer,  so  as  to  divide  part  of  the  sphincter,  produces  a  similar 
result.  The  anus  may  be  torn  by  large  hard  stools  during  defecation, 
and  some  such  tears  may  result  in  "painful  fissure." 

Near  the  anus  we  see  the  external  opening  in  cases  of  fistula  in  ano. 
A  common  form  is  the  result  of  marginal  abscesses,  superficial  to  the 
sphincters  and  lying  merely  beneath  the  skin  and  mucous  membrane. 
Their  internal  orifice  is  generally  found  a  little  above  the  junction  of  the 
skin  and  mucocutaneous  tissue,  just  within  the  grasp  of  the  sphincter. 
The  upward  extension  of  an  ischiorectal  abscess  is  resisted  by  the  levator 
ani  muscle  and  the  anal  and  rectovesical  fasciae  covering  it,  between 
which  and  the  external  sphincter  it  finds  a  point  of  least  resistance  to 
extend  toward  the  rectum,  into  which  it  usually  opens  between  the  exter- 
nal and  internal  sphincters,  about  12  mm.  (^  in.)  from  the  anus.  The 
abscess  before  opening  may  extensively  undermine  the  mucous  mem- 
brane, so  that  the  resulting  fistulous  tract  may  extend  upward,  way 
above  the  point  where  it  perforates  the  muscular  wall.  The  internal 
opening,  through  the  mucosa,  may  occur  at  the  latter  point  or  above. 
The  cure  of  a  fistula  requires  an  incision  uniting  the  internal  and  exter- 
nal openings,  often  involving  the  division  of  the  external  sphincter. 
Unless  both  sphincters  are  divided,  incontinence  of  feces  does  not  per- 
sist long.  If  the  fistulous  opening  is  into  the  anal  canal  only  and  not 
on  the  surface  an  "incomplete"  or  "blind"  internal  fistula  results.  (See 
also  p.  483,  Ischiorectal  Fossa.) 

Inspection  of  the  anus  is  of  diagnostic  importance.  Thus  in  cases  of 
obstruction  due  to  stricture  of  the  rectum,  greatly  enlarged  prostate, 
etc.,  the  anus  is  patulous  and  flabby,  while  in  fissure  it  is  tightly  closed. 

Development  and  Errors  of  Development. — The  pelvic  portion  of 
the  rectum  is  formed  by  the  blind  caudal  end  of  the  hind  gut;  the  anal 
portion  by  an  invagination  of  the  surface  at  the  site  of  the  anus.  Nor- 
mally the  septum  between  them  is  absorbed  so  as  to  form  a  continuous 
canal,  but  abnormally  it  may  leave  an  annular  constriction  at  their  junc- 
tion, or  it  may  persist  and  form  an  imperforate  anus.  In  such  cases  the 
septum  persists  (1)  as  a  thin  membranous  septum  which  bulges  with  the 
retained  meconium  and  may  be  readily  incised,  or  (2)  as  a  thicker  parti- 
tion after  division  of  which  the  rectal  mucous  membrane  must  be  brought 
down  to  the  surface  to  avoid  stricture.  Again,  (3)  there  may  be  no  anal 
invagination  whatever,  and  in  such  cases  the  lower  end  of  the  rectal  por- 
tion may  or  may  not  be  absent.  In  infants  with  obstinate  constipation 
digital  examination  of  the  rectum  must  not  be  neglected.     If  a  careful 


THE  VISCERA  OF  THE  PELVIS  417 

dissection  through  a  median  incision  prolonged  back  to  the  coccyx 
and  carried  up  in  front  of  the  coccyx  and  sacrum  fails  to  discover  the 
rectal  pouch,  an  inguinal  colostomy  must  be  made. 

In  rare  cases  the  rectum  opens  cutaneously  at  some  unusual  point 
(symphysis,  prepuce,  perineum,  sacral,  gluteal,  or  lumbar  regions),  and 
usually  by  a  long  canal  with  a  narrow  aperture.  More  often  it  opens 
into  the  genito-urinary  tract,  bladder,  urethra,  or  vagina.  Primarily 
the  allantoic  vesicle,  from  which  the  bladder  and  the  posterior  urethra 
are  formed,  was  derived  from  and  opened  into  the  hind  gut.  The  per- 
sistence of  this  connection  may  explain  the  rare  opening  between  the 
rectum  and  the  bladder.  The  rectal  pouch  in  such  cases  lies  so  high 
up  that  inguinal  colostomy  must  be  resorted  to.  The  opening  into 
the  bladder  or  urethra  is  usually  small,  and  requires  operative  relief  if 
possible.  I  have  seen  the  opening  into  the  vagina  sufficient  for  the 
purposes  of  defecation,  and  this  condition  has  been  often  reported.  In 
the  latter  condition  operation  should  be  deferred  until  after  puberty,  when 
the  increased  size  of  the  pelvis  and  perineum  facilitates  a  plastic  oper- 
ation. Women  have  even  married  and  borne  children  with  a  vaginal 
outlet  to  the  rectum  and  without  inconvenience  from  it.  Cancer  is  most 
apt  to  be  found  within  5  to  8  cm.  (2  to  3\  in.)  of  the  anus.  Owing  to  its 
comparative  painlessness  it  may  be  overlooked  until  hemorrhage  or 
obstruction  occurs.  The  relations  of  the  rectum  given  above  show  to  what 
structures  it  may  extend.     The  sacral  lymph  nodes  are  first  involved. 

In  operations  for  the  removal  of  neoplasms  or  for  resection  of  strictures 
of  the  rectum  it  may  be  approached  through  (a)  the  perineum;  (b)  the 
abdomen;  (c)  both  (a  and  b) ;  (d)  through  the  vagina;  or  (e)  from  behind. 
In  the  latter  approach  room  may  be  gained  and  the  exposure  of  the  parts 
increased  by  excising  the  coccyx.  Or,  following  Kraske's  method  or 
one  of  its  modifications,  the  lower  end  of  the  left  half,  or  both  halves,  of 
the  sacrum  may  be  permanently  or  temporarily  (osteoplastic  method) 
resected.  In  these  operations  the  lower  border  of  the  third  sacral  for- 
amen should  be  the  upper  limit  of  the  resection  of  bone,  for  if  it  is  carried 
higher  there  is  a  risk  of  permanent  paralysis  of  the  bladder  from  inter- 
ference  with  the  third  sacral  nerves.  These  operations  are  carried  out 
on  the  left  side,  for  it  is  on  that  side  that  the  lower  or  pelvic  portion  of 
the  sigmoid  loop  lies.  By  division  of  the  sacrosciatic  ligaments  or  re- 
section of  their  sacral  attachments  the  entire  sacro-iliac  notch  is  opened 
up.  When  feasible  we  may  save  the  anal  portion,  containing  the  sphinc- 
ters, and  use  it  by  suturing  the  upper  segment  to  it. 

The  Bladder. — The  shape,  position,  and  relations  of  the  bladder,  or 
urinary  reservoir,  depend  upon  age,  sex,  and  the  degree  of  distention 
of  the  organ.  The  average  capacity  is  about  a  pint  (400  to  500  c.c), 
but  may  reach  1000  c.C.  under  normal  conditions.  When  distended,  in 
of  retention,  etc.,  the  bladder  has  held  as  much  ;is  3000  to  4000  c.c. 
of  urine,  and  Tilhnix  reports  a  case  in  which  it  held  7  liters  (7000  c.c). 
On  (lie  other  hand,  a  contracted  bladder  may  contain  no  more  than  10 
to  20  c.c.  C-\  to  5  drachms).  The  bladder  of  the  male  is  somewhat 
Diore  capacious  than  that  of  the  female, 
27 


418  PELVIS  AND  PERINEUM 

Shape  and  Position  of  the  Adult  Male  Bladder. — The  form  of  the  empty 
bladder  is  a  disputed  point.  Two  forms  are  described:  (1)  the  systolic 
or  contracted  form,  in  which  the  bladder  represents  a  firm  oval,  whose 
cavity,  on  sagittal  section,  forms,  with  that  of  the  urethra,  a  continuous 
curved  slit;  (2)  the  diastolic  or  relaxed  form,  in  which  the  upper 
aspect  presents  to  the  intestines  a  cup-shaped  concavity,  and  the  cavity, 
with  that  of  the  urethra,  presents  a  Y-shaped  fissure  on  sagittal  section. 
It  is  probable  that  the  systolic  form  is  the  common  one  during  life. 

When  moderately  filled  it  is  entirely  within  the  pelvic  cavity  and 
has  a  rounded  form,  which  may  be  flattened  anteroposteriorly  or  trans- 
versely elongated  by  the  pressure  of  the  adjoining  viscera.  As  it  be- 
comes distended  it  becomes  oval,  the  convexity  of  the  superior  and  postero- 
inferior  surfaces  is  increased,  the  anterior  surface  is  flattened,  and  the 
upper  part  of  the  latter,  rising  out  of  the  pelvis,  is  in  contact  with  the  back 
of  the  anterior  belly  wall.  This  fact  is  taken  advantage  of  in  suprapubic 
cystotomy  and  tapping.  In  distention  the  upper  or  smaller  end  comes 
more  and  more  in  contact  with  the  anterior  belly  wall,  and  may  reach 
the  umbilicus  and  even,  it  is  said  (Tillaux),  the  diaphragm.  As  the  dis- 
tended bladder  is  in  direct  contact  with  the  abdominal  wall,  it  always 
gives  a  dull  or  flat  note  on  percussion.  The  distended  bladder  is  not 
quite  symmetrical,  but  deviates  slightly  to  the  right,  owing  partly  to  the 
rectum  on  the  left  side  and  partly  to  the  greater  size  of  the  right  half 
of  the  bladder.  When  distended  so  that  its  upper  end  is  at  the  upper 
margin  of  the  symphysis,  its  long  axis  is  directed  from  the  latter  point 
to  the  end  of  the  coccyx. 

The  vesical  outlet  (or  internal  urinary  meatus)  is  on  a  horizontal  line 
a  little  below  the  centre  of  the  symphysis,  about  2.5  cm.  (1  in.)  behind 
the  latter  and  5  to  6.5  cm.  (2  to  2 \  in.)  above  the  perineum.  In  disten- 
tion the  bladder  is  displaced  downward  as  well  as  upward,  depressing  the 
perineum  so  that  its  outlet  is  at  a  somewhat  lower  level,  while  in  cases  of 
prostatic  enlargement  the  outlet  may  be  displaced  upward,  even  above 
the  symphysis. 

The  bladder  lies  behind  the  anterior  pelvic  wall,  in  front  of  and  above 
the  rectum  in  the  male,  the  cervix  uteri  and  the  upper  end  of  the  vagina 
intervening  in  the  female,  and  in  contact  with  the  small  intestines  and 
the  sigmoid  loop  above  and  behind. 

Relations  to  the  Peritoneum  (Figs.  140  and  146). — The  peritoneum 
covers  the  entire  superior  surface,  the  lateral  surfaces  down  to  the  line 
of  the  obliterated  hypogastric  artery,  or  a  line  extending  from  the  urachus 
to  a  point  somewhat  below  the  summit  of  the  seminal  vesicles,  and  the 
upper  part  of  the  posterior  surface,  to  the  bottom  of  the  rectovesical 
pouch.  This  pouch  is  usually  filled  with  convolutions  of  the  small 
intestine,  separating  the  bladder  and  rectum,  and  it  reaches  to  a  point 
just  below  the  upper  ends  of  the  seminal  vesicles  and  about  2.5  cm. 
above  the  prostate  (6.5  to  7.5  cm.  from  the  anus).  It  forms  the  upper 
limit  of  the  triangular  area  over  which  the  rectum  and  bladder  are 
closely  adherent. 

Normally  the  peritoneum  lines  the  anterior  abdominal  wall  down  to 


THE  VISCERA  OF  THE  PELVIS  419 

the  symphysis  pubis,  from  which  it  passes  onto  the  upper  end  and 
superior  surface  of  the  bladder.  As  the  distended  bladder  rises  above 
the  pelvis  it  pushes  up  this  parietal  peritoneum,  which  thus  comes  to  cover 
the  upper  half  of  that  part  of  the  anterior  bladder  surface  which  extends 
above  the  symphysis,  while  the  lower  half  of  this  surface  is  in  direct 
contact  with  the  anterior  belly  wall,  just  above  the  symphysis,  without 
the  intervention  of  the  peritoneum.  It  is  this  arrangement  of  the 
peritoneum  that  renders  suprapubic  cystotomy  or  tapping  a  feasible 
and  safe  operation,  for  we  can  thus  puncture  or  open  a  distended 
bladder  above  the  symphysis  without  opening  the  peritoneum.  Excep- 
tionally the  peritoneum  is  adherent  to  the  pubes,  so  that  it  cannot  be 
pushed  up  by  the  bladder.  In  operating  on  such  a  case,  wounding 
of  the  peritoneum  would  be  likely,  but  this  wound  could  be  sutured, 
the  peritoneum  carefully  detached  below  and  drawn  upward,  and  the 
bladder  then  opened. 

Theoretically,  the  lower  half  of  that  part  of  the  anterior  bladder  sur- 
face above  the  symphysis  should  be  devoid  of  peritoneum,  no  matter 
how  high  the  bladder  rises,  but  practically  there  is  seldom  more  than 
5  to  6.2  cm.  (2  to  2\  in.)  between  the  symphysis  and  the  peritoneum, 
although  the  latter  can  be  retracted  still  farther  upward.  When  the 
bladder  reaches  half-way  from  the  symphysis  to  the  umbilicus  there 
will  be  this  5  to  6.7  cm.  of  the  anterior  abdominal  wall  above  the  sym- 
physis devoid  of  peritoneum  and  in  direct  contact  with  the  anterior 
bladder  wall.  The  use  of  Petersen's  rubber  bag,  inflated  in  the  rectum, 
prevents  the  bladder,  filled  with  eight  ounces  (250  c.c.)  of  fluid,  from  ex- 
tending downward  and  backward  toward  the  perineum,  and  at  the  same 
time  directly  raises  it  and  thus  helps  to  bring  it  in  contact  with  the  ante- 
rior belly  wall,  but  it  has  no  special  influence  in  raising  the  peritoneal  fold 
above  the  symphysis.  By  the  use  of  Trendelenburg's  position  gravity 
tends  to  bring  the  moderately  filled  bladder  above  the  symphysis  pubis 
and  in  contact  with  the  anterior  abdominal  wall,  so  that  the  rectal  bag 
may  be  discarded  as  unnecessary.  In  fact,  little  difficulty  is  found  in 
opening  the  empty  bladder,  supra  pubes,  by  the  use  of  the  Trendelen- 
burg position. 

The  anterior  surface  and  that  part  of  the  lateral  surfaces  below  the 
limit  of  the  peritoneum  are  separated  from  the  fascia  covering  the  obturator 
and  levator  ani  muscles,  of  the  anterior  and  lateral  pelvic  walls,  by  a 
quantity  of  loose  areolar  tissue  whose  meshes  contain  much  fat.  This 
ue  ensheatbs  the  vesical  vessels  and  occupies  an  area,  the  space  of 
Retzius  fcavum  Retzii),  more  or  less  triangular,  with  its  base  directed 
downward,  and  shut  in  by  the  peritoneum  above.  The  looseness  of 
this  tissue  readily  allows  changes  in  dimension  without  disturbing 
the  connections  of  the  bladder,  and  it,  also  favors  the  rapid  and  wide 
spread  of  inflam/mation  following  extraperitoneal  wounds  of  the  bladder 

with   extravasation  of   urine.      This  tissue,  or   the  subperitoneal    tissue 

continuous  with  it,  separates  the  distended  bladder  from  the  anterior 
abdominal  wall,  below  the  fold  of  the  peritoneum.  Hence  it  \b  opened 
up  in  suprapubic  cystotomy  and  traversed  by  a  trocar  in  tapping  the 


420  PELVIS  AND  PERINEUM 

bladder,  so  that  suppuration  in  this  tissue,  and  in  rare  cases  death, 
has  followed  the  latter  procedure.  It  is  also  continuous  above  and  at 
the  sides  with  the  abdominal  and  pelvic  subperitoneal  connective  tissue, 
hence  an  inflammation  in  it  may  become  widely  diffused. 

The  ureters  pierce  the  bladder  (Fig.  146)  at  the  junction  of  the  lateral 
and  posterior  surfaces,  about  3.5  to  4  cm.  (1  ^  to  If  in.)  from  each  other, 
and  the  same  distance  above  the  prostate;  just  above  the  outer  and  upper 
limits  of  the  triangular  area  of  vesicorectal  contact;  and  near  to,  although 
not  in  contact  with,  the  rectum,  so  that  a  calculus  in  the  lower  end  of  the 
ureter  may  possibly  be  palpated  through  the  rectum.  The  vasa  defer- 
entia  cross  the  lateral  bladder  wall  from  before  backward  and  above 
downward  to  reach  the  inner  side  of  the  seminal  vesicles  and  form 
the  sides  of  the  above-mentioned  triangular  area  on  the  posterior  vesical 
surface.  They  cross  the  obliterated  hypogastric  arteries,  and  thence 
to  the  above  triangular  area  they  lie  subperitoneally.  They  pass 
between  the  bladder  and  the  ureters  just  where  the  latter  pierce  the 
bladder. 

Rupture  of  the  Bladder. — Rupture  of  the  bladder  is  more  serious  when 
it  involves  in  whole  or  in  part  the  portion  covered  by  peritoneum.  Vio- 
lence applied  to  the  anterior  belly  wall  may  rupture  the  distended  bladder 
without  fracture  of  the  pelvis  or  any  external  sign  of  injury.  The  bladder 
may  be  torn  by  bony  fragments  of  a  fractured  pelvis  or,  rarely,  in  case 
of  an  injury  of  the  rectum  or  vagina.  When  the  bladder  is  distended 
by  urine,  in  neglected  cases  of  stricture,  the  urethra  gives  way,  as  a 
rule,  before  the  bladder,  and  the  urine  is  extravasated  into  the  perineum. 
But  rupture  of  the  viscus  has  resulted  in  some  rare  cases  from  con- 
genital closure  of  the  urethra  in  infants  and  in  neglected  cases  of  reten- 
tion of  urine,  especially  in  women  and  in  prostatics.  When  the  bladder 
is  artificially  overdistended  it  usually  gives  way  laterally,  below  the 
peritoneal  reflection  (Tillaux),  but  most  ruptures  (85  per  cent.)  intra 
vitam  involve,  in  part,  at  least,  the  surface  covered  by  peritoneum,  for  it 
is  this  part  that  is  thinnest  and  most  distended  when  the  bladder  is  filled. 
In  intraperitoneal  ruptures  urine  is  extravasated  into  the  peritoneal  cavity, 
which  it  irritates,  not  when  normal  and  fresh,  but  when  abnormal  or 
after  becoming  stagnant.  Hence  a  primary  condition  of  treatment 
is  the  free  drainage  of  the  bladder,  and  hence  also  the  fatality  of  such 
ruptures  unless  the  rent  is  repaired  by  suture  and  the  extravasated  urine 
is  removed  from  the  peritoneal  cavity.  The  injury  is  indicated  by 
inability  to  urinate,  the  urine  passing  through  the  rent  into  the  peritoneal 
cavity,  by  the  catheter  removing  only  a  little  blood-stained  urine,  and 
by  only  a  part  of  the  fluid  injected  returning  by  the  catheter.  Extra- 
peritoneal rupture  is  apt  to  be  on  the  anterior  wall,  so  that  the  urine  escapes 
into  the  loose  cellular  tissue  of  the  cavum  Retzii.  Cellulitis  and  abscess 
result,  though  recovery  often  ensues.  Stab  or  bullet  wounds  take  the 
same  clinical  course,  according  as  they  are  intra-  or  extraperitoneal, 
except  that  a  small  bullet  wound,  like  the  puncture  of  a  small  trocar, 
may  become  at  once  plugged  by  the  mucous  membrane  and  the  muscular 
contraction  of  the  wall,  thus  preventing  extravasation. 


THE  VISCERA  OF  THE  PELVIS  421 

Fixation  of  the  Bladder. — The  reflections  of  peritoneum  onto  the 
bladder,  known  as  its  false  ligaments,  steady  it  without  fixing  it,  while 
the  bands  of  thickened  rectovesical  fascia,  reflected  onto  its  base  and 
known  as  its  true  ligaments,  anchor  this  part.  It  is  still  further  fixed 
in  position  by  its  attachment  behind  to  the  rectum  in  the  male  and  the 
uterus  and  vagina  in  the  female,  and  by  the  connection  of  the  ureters, 
urethra,  prostate  and  the  fibromuscular  cord  of  the  urachus. 

Malposition. — In  spite  of  these  various  means  of  anchoring  the  bladder, 
and  on  account  of  the  laxity  of  the  attachments,  it  has  been  found  in 
inguinal,  femoral,  and  some  forms  of  pelvic  hemice,  especially  in  men 
over  fifty.  In  inguinal  and  femoral  hernise  the  part  herniated  may  be 
entirely  extraperitoneal  (in  75  per  cent.)  or  in  part  intraperitoneal.  An 
abnormally  high  position  of  the  bladder  may  be  due  to  prostatic,  rectal, 
or  pelvic  tumors. 

The  Bladder  Wall. — The  bladder  wall  varies  in  thickness  from  3  mm. 
(|  in.),  when  moderately  distended,  to  12  mm.  (J  in.)  or  more  when 
contracted.  The  anterior  wall  and  trigone  are  somewhat  thicker  than 
the  rest  of  the  bladder.  When  there  is  obstruction  to  the  escape  of 
urine  the  bladder  muscle  hypertrophies  from  undue  exercise,  like  other 
muscles.  In  such  cases  the  interlacing  network  of  the  internal  layer  of 
fibers  is  thickened  and  appears  as  distinct  intersecting  ridges  beneath 
the  mucous  membrane  (the  fasciculated  bladder).  The  bladder  wall  in 
the  interspaces  of  this  network  is  thinner  and  weaker,  and  its  mucous 
membrane  may  become  protruded  or  herniated  in  the  form  of  sacculi, 
by  the  increased  intravesical  pressure  (the  sacculated  bladder).  One  or 
several  of  these  sacculi  may  become  so  enlarged  as  to  allow  urine  to  stag- 
nate and  decompose,  phosphatic  deposits  to  form  and  collect,  and  calculi 
to  develop  or  become  hidden  (encysted  calculi).  When  a  calculus,  pre- 
viously contained  in  the  bladder,  slips  into  a  sacculus  the  symptoms 
suddenly  subside  and  the  stone  may  no  longer  be  felt  by  the  searcher. 
Digital  rectal  examination  may  sometimes  reveal  the  presence  of  such 
calculi.  The  ridges  of  a  fasciculated  bladder  may  become  encrusted  with 
phosphatic  deposits  and  give  rise  to  possible  errors  in  diagnosis  in  the 
use  of  the  searcher.  When  only  one  sacculus  is  developed  it  may 
become  enlarged,  even  to  the  size  of  the  bladder,  and  give  rise  to  the 
erroneous  designation  "double  bladder."  Below  and  in  front  the  longi- 
tudinal fibers  of  tin  external  layer,  known  from  its  action  as  the  detrusor 
urincB  muscle,  pass  on  each  side  in  front  of  the  prostate  to  the  back  of  the 
pubic  bones  as  the  vesicopubic  muscle,  while  superiorly  the  longitudinal 
fibers  are  continued  into  the  urachus.  The  circular  fibers  of  the  middle 
layer  are  aggregated  near  the  vesical  outlet,  where  they  are  known  as  the 
internal  sphincter  of  the  bladder,  although  Henle  has  shown  that  their 
action  i>  to  empty  the  bladder  of  the  last  drops  of  urine,  the  real  inter- 
nal sphincter  being  the  circular  fibers  oi*  the  upper  prostatic  urethra. 

The  entire  bladder  is  invested  by  the  re.cturcsic.nl  fascia,  which  is  much 
thicker  at  its  lower  part.  The  clastic  submucous  layer  is  intimately 
connected  with  the  mucous  membrane,  which  it  loosely  connects  with  the 
muscular  layers,  except  over  the  trigone,  where  the  three  layers  are  closely 


422  PELVIS  AND  PERINEUM 

adherent,  a  fact  of  importance,  for  otherwise  the  trigonal  mucous  mem- 
brane would  be  prolapsed  into  and  block  up  the  urethral  orifice  during 
micturition.  As  a  result  of  this  adhesion  the  mucous  membrane  of  the 
trigone  is  always  smooth,  while  that  of  the  rest  of  the  bladder  is  thrown 
into  rugse  when  the  bladder  is  empty.  The  density  of  the  trigonal  mucosa 
prevents  free  swelling  and  partly  accounts  for  the  pain  from  inflammation 
of  this  area.  The  laxity  of  the  mucous  membrane  elsewhere  allows  of 
the  great  changes  in  the  size  of  the  viscus.  The  mucous  membrane  is 
rose  colored,  but  over  the  trigone  it  is  somewhat  paler. 

Blood  and  Nerve  Supply. — The  blood  derived  from  the  three  ves- 
ical arteries  and  small  twigs  from  the  arteries  of  the  neighboring  parts 
(uterine  and  vaginal  in  the  female)  is  returned  by  the  veins  into  the 
internal  iliac  vein.  When  inflamed  the  mucous  membrane  is  deeply 
injected  and  bleeds  readily.  The  veins  form  plexuses  around  the  lower 
end  or  base  of  the  bladder,  which  are  connected  with  those  of  adjacent 
parts,  especially  with  those  of  the  prostate  in  the  male,  forming  the  vesi- 
coprostatic  plexus.  Hence  in  enlargement  of  the  prostate  this  plexus 
becomes  varicose  (vesical  hemorrhoids),  from  the  pressure  of  the  enlarge- 
ment upon  it.  In  such  cases  the  varicose  veins  project  into  the  bladder 
near  its  outlet,  where  they  are  liable  to  bleed  spontaneously  or  from  the 
use  of  instruments,  and  they  produce  a  swelling  and  congestion  of  the 
mucous  membrane  here  which  causes  the  frequent  micturition.  The 
bleeding  may  temporarily  relieve  the  congestion  and  the  symptoms 
caused  thereby.  Bleeding  from  the  bladder  usually  indicates  tumor  or 
stone. 

The  lymphatics  of  the  bladder  empty  into  the  external  iliac  and  hypo- 
gastric nodes  and  those  at  the  bifurcation  of  the  aorta.  Lymphatics  are 
wanting  in  the  mucous  membrane. 

The  nerves  are  derived  from  the  hypogastric  plexus,  supplying  the  muscle 
fibers,  and  from  the  third  and  fourth  sacral  nerves  supplying  principally 
sensation.  The  mucosa  of  the  greater  part  of  the  bladder  is  only  slightly 
sensitive,  as  may  be  observed  in  the  passage  of  a  sound  or  searcher;  that 
of  the  trigone,  especially  at  the  ureteral  openings,  and  in  the  neighbor- 
hood of  the  outlet  is  much  more  sensitive.  When  the  bladder  is  inflamed 
its  mucosa,  especially  that  near  the  outlet,  is  much  more  sensitive,  as 
seen  in  cases  of  cystitis  or  in  stone.  In  the  upright  position  the  stone 
gravitates  to  the  highly  sensitive  trigone,  hence  the  pain  is  more  severe 
and  micturition  is  more  frequent  during  the  day  than  at  night.  In  mic- 
turition the  stone  is  forced  against  the  outlet,  causing  great  pain  and 
perhaps  suddenly  checking  the  flow  of  urine.  Frequent  micturition  is 
usually  due  to  an  irritation  through  the  sensory  nerves  (third  and  fourth 
sacral),  setting  up  a  reflex  motor  impulse  which  passes  from  the  last  two 
dorsal  and  upper  lumbar  segments  through  the  hypogastric  plexus. 
Sudden  distention  of  the  bladder  causes  acute  pain,  but  it  may  become 
gradually  distended  with  only  a  sense  of  discomfort. 

When  the  nerves  supplying  the  bladder  are  paralyzed  from  injury  or 
disease  of  the  cord,  distention  ensues  from  lack  of  power  to  empty  it, 
and  the  consciousness  of  the  bladder  being  distended  is  lost.    Thus  we 


THE  VISCERA  OF  THE  PELVIS 


423 


have  retention  of  urine,  but  in  time  the  outlet  is  opened  up  by  the  press- 
ure and  overflow  or  incontinence  of  urine  occurs,  the  bladder  remain- 
ing distended.  In  the  child  incontinence  (usually  nocturnal)  generally 
occurs  from  irritability,  not  from  distention.  Retention  may  also  occur 
from  obstruction,  due  to  stricture,  enlarged  prostate,  etc.,  but  however 
it  occurs,  long-continued  overdistention  produces  temporary  or  permanent 
paralysis  by  overstretching  the  muscular  fibers.  Thus  the  urine  flows 
from  the  catheter  without  force,  and  catheterization  must  be  continued 
for  some  time.  The  sudden  complete  evacuation  of  all  the  urine  in  an 
overdistended  bladder,  by  removing  the  pressure  on  its  bloodvessels, 
causes  such  a  relaxation  and  overfilling  of  them  that  oozing  of  blood 
occurs  into  the  bladder.  Hence  the  advice  not  to  completely  empty  at 
once  an  overdistended  bladder.  In  cases  of  repeated  or  long-continued 
overdistention  the  ureters  become  greatly  distended.    (See  Ureters,  p.  388.) 

Fig.  146 


BUNDLES    OF     LONGI- 
TUDINAL   MUSCLE 
FIBRES    FROM 
URETER 


Trigone  of  the  bladder  with  a  flap  of  mucosa  dissected  up  from  the  greater  part  of  it,  showing 
the  mode  of  termination  of  the  ureter  and  the  prolongation  of  the  bundles  of  its  longitudinal 
muscle  ftben  along  the  boundaries  of  the  trigone.  A  grooved  director  leads  to  post-trigonal 
pouch.      (Testut.) 

The  Interior  of  the  ^Bladder. — The  interior  of  the  bladder  presents 
three  orifices:  the  outlet  or  internal  urinary  meatus,  at  the  most  dependent 
pju-t  of  the  bladder  in  the  ereel  position  and  at  the  apex  of  an  equilateral 
triangle,  the  trigone,  whose  two  other  angles  are  formed  by  the  orifices 
of  the  two  ureters,  each  18  to  25  mm.  (f  to  1  in.)  from  the  outlet.  The 
vicinity  of  the  ureteral  orifice  is  congested  or  ulcerated  in  tuberculosis  of 
the  kidney  on  the  same  side.    Connecting  the  two  ureteral  orifices  and 

bounding  the  base  of  the  trigone  is  an  arehed  elevation  (plica  ureterica), 

due  to  a  band  of  muscle  fibers  continued  from  the  ureters.     In  chronic 

of  obstruction,  as  in  cases  due  to  prostatic  hypertrophy,  this 

ridge  forms  the  anterior  boundary  of  the  depression  known  as  the  post- 


424  PELVIS  AND  PERINEUM 

prostatic  pouch  {fossa  retro-ureterica).  The  longitudinal  mesial  ridge 
of  mucous  membrane,  the  uvula  vesica?  (or  uvula  of  Lieutaud),  passes 
from  the  middle  of  the  above  ridge  to  near  the  outlet,  where  it  is  most 
prominent.  It  is  especially  marked  in  old  age,  and  corresponds  to  the 
middle  portion  of  the  prostate. 

The  ureters,  reaching  the  bladder  3.5  to  4  cm.  (1^  to  If  in.)  apart,  pass 
so  obliquely  through  its  wall  for  12  to  18  mm.  (£  to  f  in.)  that  their 
oblique  passage  serves  the  purpose  of  a  valve,  preventing  reflux  from  the 
bladder  and  acting  more  perfectly  the  fuller  the  bladder.  Under  patho- 
logical conditions  the  valvular  action  may  be  imperfect,  allowing  back- 
ward flow,  and  Lewin's  experiments  on  rabbits  would  indicate  that 
the  same  may  occur  under  normal  conditions  when  the  bladder  is  not 
too  full. 

The  Female  Bladder. — The  female  bladder  has  its  longest  diameter 
transversely,  owing  to  the  greater  width  of  the  female  pelvis  and  the 
presence  of  the  uterus  and  vagina  behind  it.  Owing  to  the  less  depth 
of  the  symphysis,  the  outlet  is  relatively  lower,  i.  e.,  behind  the  lower  end 
of  the  symphysis;  and,  there  being  no  prostate,  it  is  a  trifle  nearer  the 
symphysis  and  very  distensible.  This  distensibility  of  the  outlet,  in  con- 
nection with  the  shortness  and  dilatability  of  the  urethra,  enables  us  to 
explore  the  female  bladder  with  the  finger,  to  remove  stones  and  foreign 
bodies  through  the  urethra,  and  to  more  readily  examine  the  interior 
of  the  bladder  with  the  cystoscope.  For  the  same  reason  stone  and 
cystitis  are  less  common,  and  foreign  bodies,  introduced  per  urethram, 
more  common,  than  in  the  male.  The  peritoneum  does  not  descend  so 
low  on  the  posterior  surface  in  the  uterovesical  pouch,  which  separates 
the  bladder  from  the  body  of  the  uterus,  as  in  the  male  in  the  recto- 
vesical pouch.  Below  this  pouch  the  bladder  is  in  contact  with  the  cervix 
uteri  and  the  upper  half  of  the  vagina.  A  slight  continuation  of  the 
subperitoneal  connective  tissue  extends  between  the  bladder  and  the 
cervix,  thus  facilitating  their  separation  in  removal  of  the  cervix  or 
uterus,  if  the  operator  follows  this  tissue  layer.  The  close  relation 
of  the  bladder  and  the  vagina  explains  the  frequency  of  vesicovaginal 
fistula?,  which  are  apt  to  follow  a  tear  or  sloughing  of  the  anterior  vaginal 
wall,  the  result  of  difficult  labor.  The  ureteral  orifice  is  2.5  to  3  cm. 
(1  to  1\  in.)  below  the  cervix  uteri  and  opposite  the  middle  of  the  vagina, 
hence  calculi  can  be  felt  per  vaginam  in  the  lower  ends  of  the  ureters. 
The  latter  are  also  in  danger  of  being  injured  in  operations  on  the  cervix. 

The  Bladder  in  the  Infant. — The  bladder  in  the  infant  is  pear-shaped, 
with  the  small  end  above  and  in  front  at  the  urachus,  which  represents 
the  stalk  of  the  pear.  At  birth  the  outlet  is  behind  the  upper  margin 
of  the  symphysis  and  the  bladder  is  largely  in  the  abdomen  and  entirely 
above  the  level  of  the  symphysis,  only  about  one-half  of  the  organ  being 
below  the  pelvic  brim,  as  the  pelvis  is  small  and  occupied  mainly  by  the 
rectum.  Hence  in  perineal  lithotomy  in  young  children  the  knife  must 
be  directed  well  upward  to  reach  the  bladder.  The  position  and  rela- 
tions of  the  bladder  begin  to  change  when  the  child  commences  to  walk, 
and  are  about  like  those  of  the  adult  at  the  age  of  six  years.     Before  this 


THE  VISCERA  OF  THE  PELVIS  425 

condition  is  reached  the  anterior  wall  of  the  bladder,  uncovered  by  peri- 
toneum, is  in  contact  with  the  anterior  abdominal  wall  and  readily  acces- 
sible to  suprapubic  operations  or  puncture.  In  young  male  children  the 
rectovesical  fold  extends  nearly  or  quite  to  the  base  of  the  very  small 
prostate,  which  brings  it  very  close  to  the  vesical  outlet;  in  fact,  at  birth 
it  reaches  this  level.  The  bladder  is  more  movable  owing  to  the  unde- 
veloped prostate,  etc.  The  bladder  wall  is  so  thin  that  it  is  said  that  a 
•'click"  may  be  elicited  through  this  wall  from  the  pelvic  bones,  in 
sounding  for  stones. 

Formation. — The  bladder,  female  urethra,  and  the  prostatic  and 
membranous  parts  of  the  male  urethra  are  formed  by  that  portion 
of  the  allantoic  vesicle  which  lies  within  the  body  cavity  and  extends 
between  the  hind  gut  and  the  umbilicus.  The  upper  part  of  this  is 
normally  obliterated  to  form  the  urachus,  the  lower  part  is  partitioned 
off  from  the  cloaca,  or  common  opening  of  the  urinary  and  alimentary 
tracts,  by  the  growth  of  a  partition  which  forms  the  perineum. 

Malformations. — Faulty  growth  of  this  partition  may  lead  to  fis- 
tulas between  the  rectum  and  bladder  or  urethra.  Exstrophy,  or  con- 
genital hiatus  of  the  bladder,  and  patency  of  the  urachus  have  been 
referred  to  under  Anterior  Abodminal  Walls  (pp.  282  and  290),  recto- 
vesical fistula  under  Rectum  (p.  417).  These  are  congenital  conditions, 
depending  upon  errors  of  development. 

Newgrowths. — Newgrowths  of  the  bladder  include  epithelioma,  fibroma, 
myoma,  and,  in  early  life,  sarcoma.  They  are  especially  apt  to  take 
on  a  villous  form  and  to  involve,  like  other  pathological  processes, 
the  lower  part  of  the  bladder,  where  they  may  occasionally  obstruct  the 
outlet  and  bleed  freely.  The  contents  of  the  posterior  urethra  can 
pass  readily  into  the  bladder,  those  of  the  anterior  urethra  only  by 
injection  under  high  pressure.  The  bladder  may  be  reached  and  opened 
for  exploration,  drainage,  or  the  removal  of  stone,  foreign  bodies,  tumors, 
etc.,  by  two  routes:  (1)  perineal  (see  Perineum);  (2)  suprapubic  (see  pp. 
2s.",  and  419). 

The  Prostate.— The  prostate  (Figs.  140, 147, 156,  157,  and  158)  is  an 
elastic,  contractile  organ  of  the  male  generative  system  which  embraces 
the  vesical  outlet  and  encloses  the  first  (prostatic)  portion  of  the  urethra, 
in  which  parts  of  the  urinary  system  the  effects  of  its  pathological  changes 
are  chiefly  noticed.  That  it  belongs  to  the  generative  rather  than  the 
urinary  organs  is  shown  by  its  small  size  during  childhood,  its  sudden 
growth  at  puberty  (together  with  the  testicles,  etc.),  its  atrophy  or  small 
size  after  castration  and  in  eunuchs,  and  its  anatomical  relations  with 
the  ejaculatory  ducts  and  the  prostatic  utricle.  These  facts  led  to  the 
luggestion,  by  J.  William  While,  of  castration  for  prostatic  hypertrophy. 

In  size  and  shape  (Ik-  adult  prostate  is  no!  unlike  a  Spanish  chestnut, 
meaaurni'j  about  3  to  3.5  cm.  (lj  in.)  from  base  to  apex,  3.5  to  4  cm. 
{\\  in.)  transversely,  and  2.5  em.  (1  in.)  from  before  backward,  and 
Weighing  <>  drams.  When  the  gland  is  appreciably  larger  (according 
to  Sir  II.  Thompson,  when  if.  weighs  one  ounee  and  measures  two 
inches  transversely),  hypertrophy  or  enlargement  of  the  prostate  is  said 


426  PELVIS  AND  PERINEUM 

to  exist.  This  occasionally  occurs  earlier,  but  in  about  one-third  of 
all  men  over  fifty  years  it  is  present  in  some  degree,  and  in  10  per  cent, 
of  males  over  fifty-five  it  is  of  pathological  importance.  Its  cause  is 
unknown,  but  various  theories  attribute  it  to  (a)  arteriosclerosis  (Guyon) ; 
changes  compensatory  to  (6)  primary  changes  in  the  bladder  (Harrison) ; 
or  (c)  to  deterioration  in  the  prostatic  secretion;  (d)  a  growth  analogous 
to  uterine  fibromyomata  (Thompson);  (e)  infection  (especially  gono- 
coccal), etc.  It  may  principally  affect  any  of  the  component  elements 
of  the  gland  or  the  lateral  or  median  portions  of  it.  In  addition,  prostatic 
enlargement  may  be  due  to  prostatitis,  abscess,  tuberculosis,  carcinoma, 
etc. 

The  anatomical  effects  of  enlargement  are  to  lengthen  and  compress 
the  prostatic  urethra,  to  increase  its  curvature  in  many  cases  and  some- 
times to  produce  a  lateral  curvature  (due  to  the  greater  enlargement 
of  one  side),  and  to  cause  the  gland  to  project  in  the  directions  of  least 
resistance,  backward  into  the  rectum  and  upward  into  the  bladder,  so 
as  to  raise  the  outlet  above  the  most  dependent  part  of  the  bladder 
and  lead  to  the  formation  of  the  postprostatic  pouch,  below  the  level  of 
the  vesical  outlet.  The  physiological  effects  are:  (1)  increased  difficulty 
of  micturition,  due  to  compression  of  the  urethra  and  obstruction  of 
the  vesical  outlet  by  a  prominent  middle  portion  and  by  raising  the 
outlet;  (2)  increased  frequency  of  micturition,  due  to  congestion  of 
the  lower  end  of  the  bladder  from  the  pressure  of  the  enlargement  on  the 
vesicoprostatic  plexus;  and  (3)  the  inability  to  empty  the  bladder  owing 
to  the  elevation  of  the  vesical  outlet  and  the  presence  of  the  postprostatic 
pouch,  resulting  in  the  presence  of  residual  urine  and  the  danger  of 
decomposition  of  the  stagnant  urine. 

As  a  rule  the  enlargement  implicates  the  prostate  pretty  uniformly. 
If  the  lateral  lobes  are  chiefly  involved,  the  gland  may  attain  consider- 
able size  without  causing  serious  symptoms,  whereas  a  trifling  enlarge- 
ment of  the  middle  portion  or  of  the  "  pre-spermatic  group"  (Albarran) 
of  glands  beneath  the  floor  of  the  vesical  outlet  may  cause  marked 
obstruction.  Occasionally  a  pedunculated  median  growth  projects  into 
the  bladder  and  obstructs  the  outlet  like  a  ball  valve. 
(PnWe  can  clearly  distinguish  two  lateral  lobes  of  the  prostate,  espe- 
cially when  we  look  at  the  posterior  surface  where  they  are  separated  by 
a  shallow  furrow.  This  widens  out  above  into  a  wedge-shaped  furrow, 
which  is  continuous  with  a  transverse  furrow  or  slit  at  the  junction  of 
the  posterior  surface  and  the  base,  in  which  the  ejaculatory  ducts  enter 
the  prostate.  Between  this  latter  furrow  and  the  course  of  the  ejaculatory 
ducts  posteriorly,  the  urethra  in  front  and  the  diverging  upper  ends  of 
the  lateral  lobes  on  the  sides,  lies  the  "middle  portion"  or  so-called 
"middle  lobe."  When  normal  it  is  scarcely  an  anatomical  entity,  but  in 
some  cases  of  prostatic  enlargement  this  part  may  be  principally  or  ex- 
clusively enlarged.  In  such  cases,  as  it  corresponds  to  the  uvula  vesicae, 
it  projects  into  and  obstructs  the  vesical  outlet,  occasionally  as  a  peduncu- 
lated tumor.  The  base  of  the  prostate,  surrounding  the  vesical  outlet, 
receives  the  latter  in  a  funnel-shaped  depression  somewhat  in  front 


PLATE  XL 


FIG.   147 


MIDDLE ^ 

HEMOR-  M/'//'. 

RHOIDAL 
ARTERY 


LOWE 
END    OF 
RECTO- 
VESICAL 
POUCH 
PROSTATO- 
PERITON. 
APONEU- 
ROSIS 

RECTO 
VESICAL 
FASC. 


OBLITER- 
ATED 
HYPO- 
GASTRIC 
ARTERY 


VESIC.   SEMINAL. 


DORSAL 
VEIN    OF 
PFNIS 


kPSULE    OF 
PROSTATE 


Relative  Position  of  the  Bladder,  Ureter,  Rectum,  Prostate, 
Seminal  Vesicles,  Vas  Deferens,  and  their  Vessels,  viewed  from 
the  right  side.     (Joessel.) 


THE  VISCERA  OF  THE  PELVIS  427 

of  its  middle.  The  prostatic  urethra  traverses  the  gland  from  base 
to  apex  a  little  in  front  of  its  centre;  rarely  it  merely  grooves  the  anterior 
surface  or,  in  other  cases,  passes  more  posteriorly. 

The  position  of  the  prostate  is  such  that  its  axis  from  base  to  apex 
is  nearly  vertical  in  the  erect  position.  The  apex,  resting  upon  the 
deep  layer  of  the  triangular  ligament,  lies  12  to  18  mm.  (^  to  f  in.)  be- 
hind and  a  little  below  the  lower  end  of  the  symphysis,  and  3  to  3.7  cm. 
(1^-  to  H  in.)  from  the  margin  of  the  anus.  The  posterior  surface  forms 
an  angle  of  45  degrees  with  the  horizon;  the  anterior  is  nearly  vertical. 

Of  the  relations  of  the  prostate,  that  of  the  posterior  surface  to  the 
anterior  aspect  of  the  lower  end  of  the  pelvic  portion  of  the  rectum  is  of 
especial  importance,  for  it  allows  of  easy  examination  through  the  rectum, 
the  two  being  separated  only  by  a  little  loose  connective  tissue  in  addi- 
tion to  the  capsule  of  the  prostate.  It  is  through  the  rectum  that  we 
can  readily  distinguish  enlargements  of  the  prostate  unless  there  is 
hypertrophy  of  the  "middle  lobe"  alone,  when  nothing  can  be  made 
out  by  rectal  touch.  The  lower  ends  of  the  seminal  vesicles  and  the 
ampullae  of  the  vasa  deferentia  are  in  relation  with  the  posterosuperior 
aspect  of  the  "middle  portion."  On  the  sides  it  is  in  relation  with  the 
levator  ani  muscles,  including  their  inner  and  lower  borders,  and  in 
"lateral  prostatectomy"  we  find  that  it  is  this  muscle  and  its  ensheathing 
fascia?  which  separate  the  prostate  from  the  ischiorectal  fossa.  The 
base  of  the  prostate  is  in  relation  with  the  bladder  for  a  considerably 
greater  distance  behind  than  in  front  of  the  vesical  outlet.  It  is  held 
fixed  in  position  by  the  parts  mentioned  in  relation  with  it,  viz.,  bladder, 
rectum,  ejaculatory  ducts,  urethra,  levator  ani,  deep  triangular  ligament, 
and  its  outer  fibrous  capsule,  formed  of  the  rectovesical  fascia  and 
continuous  below  with  the  deep  triangular  ligament. 

This  capsule  explains  in  part  the  course  of  prostatic  abscess,  i.  e.,  that 
they  seldom  extend  upward  and  open  into  the  pelvis,  for  this  course  is 
resisted  by  the  pelvic  fascia  reflected  from  the  pelvic  floor  to  the  base 
of  the  prostate  to  form  its  capsule.  Prostatic  abscesses  extend  in  the 
directions  of  least  resistance,  and  accordingly  open  most  often  into  the 
urethra,  next  in  order  of  frequency  into  the  rectum.  (See  Relations 
of  the  Prostate.)  Less  frequently  they  open  in  the  perineum,  which 
they  reach  by  running  along  the  side  of  the  rectum,  for  the  dense  tri- 
angular ligament  prevents  their  passage  more  anteriorly.  They  may 
be  a  fjiii.sc  of  peri-anal  fistula,  and  such  fistulas  are  apt  to  recur  after 
the  ordinary  fistula  operation.  When  they  perforate  both  the  urethra  and 
rectum  a  urethrorectal  fistula  may  result.  Prostatic  abscess  is  the  result 
of  a  prostatitis,  usually  of  gonorrheal  origin.  Such  an  inflammation  may 
not  go  on  to  abscess  formation,  but  stop  short  of  it  with  enlargement 
and  tenderness  of  the  gland,  readily  felt  by  rectum,  and  \vith  frequent, 
painful,  and  difficult  micturition.  The  firmness  of  the  capsule  goes  to 
explain  the  severe  pain  in  acute  prostatas. 

Between  this  capsule  and  the  organ  itself,  surrounded   by  its  own  true 

llle,  is  found  the  prostatic  plexus  of  veins,  most  marked  ;if  the  sides 

and  in  front,  nerving  at  the  latter  part  the  dorsal  vein  of  the  penis, 


428  PELVIS  AND  PERINEUM 

through  the  pudendal  plexus.  The  plexus  also  connects  with  the  neigh- 
boring veins,  the  hemorrhoidal  of  the  rectum,  and  the  vesical,  especially 
with  the  latter,  with  which  it  forms  the  vesicoprostatic  plexus,  in  the 
groove  between  the  prostate  and  the  bladder.  Phleboliths  occur  more 
commonly  here  than  in  any  other  veins.  As  these  veins  are  cut  in  lateral 
lithotomy  and  other  operations  they  may  afford  an  entrance  for  septic 
matter  in  cases  of  pyemia  following  such  operations.  These  veins  empty 
into  the  internal  iliac  vein. 

In  structure  the  prostate  is  a  musculoglandular  organ.  The  glands 
are  chiefly  at  the  posterior  and  lateral  parts  of  the  organ,  and  open  in 
the  floor  of  the  sinuses  of  the  prostatic  urethra.  They  sometimes  con- 
tain pathological  concretions.  The  anterior  part  of  the  organ  in  general 
contains  but  few  glands.  The  muscle  tissue  is  largely  of  the  unstriped 
variety,  but  a  certain  amount  of  striped  fibers  lie  in  front  of  the  prostatic 
urethra  and  surround  the  lower  part  of  it,  forming  the  external  sphincter 
vesica?,  continuous  below  with  the  compressor  urethras  muscle.  The 
unstriped  fibers  are  arranged  as  follows :  (1)  They  surround  the  urethra, 
forming  the  internal  sphincter  of  the  bladder  at  the  upper  end  of  the 
urethra,  where  they  are  derived  from  the  deeper  layer  of  the  muscle  of  the 
trigone;  (2)  they  are  condensed  into  a  musculo  fibrous  sheath,  between 
which  and  the  fibrous  capsule  lies  the  venous  plexus;  and  (3)  they  form 
part  of  the  proper  stroma  of  the  organ.  The  fibrous  and  muscular  tissue 
of  the  anterior  and  posterior  commissures  forms  a  median  anteroposte- 
rior septum  or  bridge  of  tissue  that  unites  the  lateral  lobes  in  front  of 
and  behind  Jhe  urethra,  which  it  encloses  and  blends  with.  According 
to  some  (Freyer)  the  inner  sheath  of  the  gland  is  formed  by  the  fibrous 
sheaths  of  the  two  lateral  halves  of  the  embryonic  prostate,  which  join 
together,  enveloping  the  urethra.  This  explains  how,  in  hypertrophy, 
each  lateral  lobe  in  its  sheath  may  be  shelled  out  without  injury  to 
the  urethra  or  the  ejaculatory  ducts,  which  latter  do  not  penetrate  this 
sheath. 

The  prostate  may  be  reached  for  operation  through  the  perineum  or 
through  the  bladder,  suprapubically.  It  is  only  separated  from  the 
ischiorectal  fossa  by  the  levator  ani  muscle  and  its  two  investing  fasciae, 
the  anal  and  rectovesical.  From  below  it  may  be  most  freely  exposed 
by  an  angular  or  curved  transverse  incision  in  front  of  the  rectum 
(Zuckerkandl's  incision),  or  an  anteroposterior  incision  curving  around 
the  left  side  of  the  rectum  (v.  DittePs  incision). 

The  two  ejaculatory  ducts  (Figs.  156  and  158)  are  the  outlet  into  the 
prostatic  urethra  of  the  seminal  vesicles  and  the  vasa  deferentia,  by  the 
junction  of  which,  on  either  side,  they  are  formed  near  the  postero- 
superior  margin  of  the  prostate,  6  to  8  mm.  behind  and  below  the  vesical 
outlet.  They  pass  thence  downward  and  forward  behind  the  middle 
lobe  and  between  it  and  the  lateral  lobes  of  the  prostate,  and  then  along 
the  sides  of  the  prostatic  utricle  to  open  on  either  side  of  the  mouth  of 
the  latter  on  the  verumontanum,  in  the  floor  of  the  prostatic  urethra. 
They  are  about  18  to  20  mm.  (f  in.)  long,  converge  slightly,  and  de- 
crease in  size  from  above  downward. 


THE  VISCERA  OF  THE  PELVIS  429 

In  sagittal  incisions  in  the  prostate  behind  the  urethra,  not  exactly 
median  in  position,  one  of  these  ducts  is  wounded.  This  is  objection- 
able, especially  in  young  subjects,  as  it  may  result  in  closure  of  the 
duct.  An  oblique  radiating  incision,  as  in  lateral  lithotomy,  is  less 
likely  to  wound  them.  Inflammation  may  extend  through  the  duct  to 
the  vas  deferens  and  thence  to  the  epididymis  from  the  bruising  of  the 
aperture  of  the  duct  in  the  extraction  of  a  stone  or  a  fragment  of  a  stone 
or  in  the  passage  of  an  instrument,  or  from  the  extension  of  a  urethritis. 
This  and  not  metastasis  is  the  usual  origin  of  epididymitis,  as  is  indicated 
by  the  slight  enlargement  and  tenderness  of  the  vas,  although  attention  is 
not  usually  called  to  it  by  any  marked  symptoms.  The  injection  into 
the  prostatic  urethra  of  solutions  of  nitrate  of  silver,  etc.,  in  cases  of 
derangement  of  the  sexual  function  is  intended  to  act  upon  the  openings 
of  the  ejaculatory  ducts. 

The  Seminal  Vesicles. — The  two  vesiculseseminales  (Figs.  140and  147) 
are  symmetrically  placed  on  the  two  sides  between  the  base  of  the  bladder 
and  the  front  of  the  pelvic  portion  of  the  rectum.  They  extend  from  the 
ejaculatory  ducts,  at  the  base  of  the  prostate,  upward,  backward,  and 
outward  for  about  4  to  5  cm.  (2  in.),  at  an  angle  of  50  to  60  degrees  with 
the  horizon.  Their  position  varies  somewhat  with  the  condition  of  the 
bladder  and  the  rectum.  Posteriorly  their  fibromuscular  capsule  is  con- 
nected with  that  part  of  the  rectovesical  fascia  which  forms  the  fascial 
covering  of  the  rectum.  The  lower  ends  of  the  vesicles  are  palpable 
through  the  rectum,  above  the  base  of  the  prostate,  especially  if  the  hand 
presses  the  surface  about  the  anus  strongly  upward  and  the  prostate  is  not 
enlarged.  The  seminal  vesicles  are  more  readily  palpated  when  the  blad- 
der is  full  and  when  they  are  enlarged  or  hardened  by  disease.  By  the 
finger  in  the  rectum  we  can  press  downward  the  contents  of  the  vesicles 
into  the  prostatic  urethra  and  thence  externally.  The  same  result  may 
follow  the  passage  of  large,  hard,  fecal  masses  through  the  rectum, 
which  may  cause  a  young  male  neurasthenic  to  fancy  he  has  spermator- 
rhea. They  are  sometimes  massaged  through  the  rectum  as  a  thera- 
peutic  measure  in  chronic  vesiculitis.  The  upper  fourth  of  the  seminal 
vesicles  is  covered  behind  by  the  peritoneum  of  the  rectovesical  pouch, 
which  separates  this  portion  from  the  rectum.  This  pouch  sinks  some- 
what lower  in  the  space  between  the  vesicles. 

Anteriorly  the  capsule  of  the  seminal  vesicles  is  connected  by  loose 
with  the  base  of  the  bladder.  The  vesicles,  together  with  the 
ampullae  of  the  vasa  deferentia  along  their  mesial  borders,  lie  along 
the  lateral  borders  of  the  trigone  of  the  bladder  and  the  fossa  retro- 
ureterica,  so  that  in  distention  of  the  bladder  the  latter  fossa  projects 
between  the  seminal  vesicles.  The  upper  ends  or  bases  of  the  vesicles 
are  6  U)  7  Cm.  apart;  they  approach  the  lateral  pelvic  walls  and  overlap 
the  lower  ends  of  the  iintrrs  jusi  before  the  latter  pierce  the  bladder. 

The  vesicles  are  loosely  connected  with  their  capsules  from  which 
are  readily  shelled  out.    When  so  shelled  out  we  see  that  their 

lobulated  appearance  i-,  due  to  the  con  rotations  of  a  blind   tube,  about 
1*)  cm.  [A  in.)  or  more  long,  and  to  numerous  blind  gacculi  and  lateral 


430  PELVIS  AND  PERINEUM 

branches.  The  capsule  is  continuous  with  that  of  the  prostate  and  with 
the  rectovesical  fascia,  and  contains  several  scattered  muscle  fibers. 
Enclosed  within  its  capsule  each  vesicle  presents  an  elongated  triangular 
shape,  the  lower  and  smaller  end  of  which  opens  by  a  free  aperture 
into  the  lateral  wall  of  the  lower  end  of  the  ampulla,  of  which  it  is  a 
sacculated  appendage.  The  seminal  vesicles  vary  much  in  size  not 
only  in  different  persons,  but  on  the  two  sides  of  the  same  person.  One 
or  both  vesicles  have  been  found  wanting,  the  latter  condition  usually 
in  anorchids. 

The  vesicles  secrete  an  albuminous  fluid,  which  usually  contains  a 
few  spermatozoa  which  have  wandered  there  by  their  own  motility,  for 
it  is  now  thought  improbable  that  they  serve  as  reservoirs  for  the  semen. 
The  contents  of  the  vesicles  add  to  the  bulk  of  the  fluid  ejaculated. 

The  vesicles  from  their  position,  about  the  centre  of  the  pelvis,  are 
well  protected  from  injury,  which  rarely  affects  them.  Inflammation 
(usually  gonorrheal)  may  extend  into  the  seminal  vesicles  from  the 
prostate  through  the  ejaculatory  ducts,  and,  if  an  abscess  forms,  the 
relations  of  the  vesicles  show  that  it  may  break  into  the  bladder,  rectum, 
or  peritoneal  cavity,  and  that  it  may  involve  the  vas,  the  prostate,  or  the 
ureter.  Tuberculosis  of  the  seminal  vesicles  is  not  uncommon  and 
forms  one  of  the  varieties  of  genito-urinary  tuberculosis.  It  is  usually 
an  extension  from  neighboring  parts  (prostate,  epididymis). 

The  seminal  vesicles  may  be  exposed  and  removed  through  perineal 
incisions  similar  to  those  used  to  expose  the  prostate,  separating  the 
latter  from  the  rectum  until  the  vesicles  are  reached. 

The  Vas  Deferens  (Fig.  147).— This  continuation  of  the  epididymis, 
or  efferent  duct  of  the  testis,  extends  from  the  globus  minor  to  the 
ejaculatory  duct.  In  the  scrotum  it  lies  behind  the  testis  and  internal  to 
the  epididymis,  thence  it  extends  upward  to  the  external  ring  as  one  of 
the  constituents  of  the  spermatic  cord,  behind  and  internal  to  the  other 
constituents  of  the  cord.  In  this  position  it  is  readily  felt  and  avoided 
in  operations  for  varicocele  or  hernia.  It  is  readily  felt  as  a  uniform, 
firm,  round,  whipcord-like  structure.  Its  firmness  is  due  to  the  thickness 
of  its  walls  as  compared  with  the  size  of  the  lumen.  When  affected  by 
tuberculous  disease  it  is  characteristically  nodular.  In  cases  of  inver- 
sion of  the  testis  its  position  is  reversed,  lying  in  front  of  the  testis  and 
the  other  elements  of  the  spermatic  cord. 

At  the  external  abdominal  ring  it  lies  behind  and  internal  to  the 
neck  of  the  sac  of  an  oblique  inguinal  hernia  and  external  to  that  of 
a  direct  inguinal  hernia.  It  may  become  adherent  to  the  coverings  of  a 
hernia,  especially  in  cases  of  long  standing.  After  entering  the  abdomen 
through  the  internal  ring  it  soon  diverges  from  the  spermatic  vessels 
and,  looping  above  the  arch  of  the  deep  epigastric  artery,  enters  the 
pelvis  near  the  iliopubic  eminence.  It  then  runs  backward  and  down- 
ward on  the  lateral  pelvic  wall,  and  thence  onto  the  posterolateral 
aspect  of  the  bladder.  In  this  part  of  its  course  it  crosses  the  external 
iliac  vein,  obturator  vessels  and  nerve,  and  the  obliterated  hypogastric 
artery. 


THE  FEMALE  PELVIC  GENITAL  ORGANS  431 

On  the  bladder  it  lies  on  the  vesical  side  of  the  obliterated  hypogastric 
artery  and  the  lower  end  of  the  ureter,  separated  from  the  latter  by  a  layer 
of  perivesical  fat  1  cm.  (h  in.)  thick.  Thence  it  bends  down  on  the  mesial 
side  of  the  ureter  onto  the  base  of  the  bladder,  where  it  lies  between  it 
and  the  rectum,  adjacent  and  internal  to  the  vesiculae  seminales.  Here 
it  becomes  enlarged  and  somewhat  sacculated  as  the  ampulla,  whose 
relations  are  similar  to  those  of  the  seminal  vesicles  already  described 
{q.  v.).  Near  the  base  of  the  prostate  and  the  inferior  angle  of  the 
external  trigone  it  narrows  down  and  is  joined  by  the  seminal  vesicle 
to  form  the  ejaculatory  duct. 

The  entire  pelvic  portion  of  the  vas,  except  that  at  the  base  of  the 
bladder,  is  subperitoneal  and  quite  closely  attached  to  the  peritoneum, 
so  that  when  the  latter  is  raised  it  tends  to  follow  it. 

The  infection  from  a  urethritis  may  extend  along  the  vas  to  the  epi- 
didymis, giving  rise  to  epididymitis.  In  such  cases  the  vas  becomes 
swollen  to  the  size  of  a  leadpencil  and  tender,  but  the  inflammation  of 
the  vas  speedily  subsides  and  generally  leaves  no  trace.  The  ampulla 
of  the  vas  may  be  palpated,  exposed,  and  operated  upon  in  the  same 
way  as  the  seminal  vesicles. 

The  artery  of  the  vas  deferens,  derived  either  from  the  superior  or 
one  of  the  inferior  vesical  arteries,  forms  an  important  anastomosis  with 
the  spermatic  artery  at  the  lower  end  of  the  epididymis,  which  is  suffi- 
cient to  nourish  the  testis  when  the  spermatic  artery  is  ligated  in  the 
operation  for  varicocele. 


THE  FEMALE  PELVIC  GENITAL  ORGANS. 

The  Uterus. — The  uterus  lies  within  the  pelvis  between  the  bladder  and 
the  rectum,  and,  together  with  its  lateral  or  broad  ligaments,  divides  the 
pelvic  cavity  into  an  anterior  or  uterovesical  and  a  posterior  or  uterorectal 
compartment.  Its  size  and  shape  vary  with  age  and  many  physiologi- 
cal and  pathological  conditions.  In  shape  it  is  pyriform  and  flattened 
from  before  backward,  except  when  affected  by  unsymmetrical  new- 
growths  like  fibromvomata,  cancer,  etc.  The  fundus  is  on  a  level  with 
the  uterine  ends  of  the  Fallopian  tubes  in  nulliparae  and  about  1  cm. 
in  multipara.  In  the  infant  and  the  child  before  puberty  it  is  rela- 
tively sum II  in  size,  the  cervix  is  larger  than  the  body,  and  the  intra- 
raginal  segment  of  the  cervix  is  relatively  large.  In  the  uterus  of  a 
jroung  adult  ririjin  the  length  is  about  equally  divided  between  the 
cervix  and  the  body.  In  the  nuHiparous  married  woman  the  body 
becomes  somewhat  larger  than  the  cervical  portion,  and  the  entire 
organ  measures  about  6.5  cm.  (2h  in.)  in  length  and  4  cm.  (1£  in.)  in 
mates!  breadth.  When  completely  involuted  after  childbirth  the  uterus 
is  always  somewhat  larger  (about  one-fifth)  than  before  conception,  and 

th<-  length  of  the  body  is  twice  that  of  the  cervix.     In  old  age  the  entire 

Organ  atrophies,  and   mis   process  begins  after  functional  activity  ceases 

at  the  menopau  < . 


432  PELVIS  AND  PERINEUM 

The  weight  in  nulliparae  is  about  one  ounce  (30  gm.) ,  in  multipara  an 
ounce  and  a  half,  in  old  age  it  may  be  as  little  as  one  to  two  drams, 
while  at  full  term  it  may  vary  between  twenty-two  and  forty-six  ounces. 
The  weight  is  somewhat  increased  during  menstruation.  Increase  of 
weight  may  be  due  to  pregnancy,  inflammation,  newgrowths,  etc.,  and 
is  a  cause  of  various  malpositions. 

Position. — The  uterus  of  the  infant  and  child  projects  above  the  pelvic 
brim  and  lies  almost  wholly  in  the  abdomen,  compressed  between 
the  bladder  and  rectum  and  without  flexion,  as  a  rule.  Before  puberty 
it  comes  to  lie  entirely  below  the  pelvic  brim,  but  above  a  horizontal 
plane  passing  through  the  upper  end  of  the  symphysis,  and  remains  so 
unless  enlarged  by  pregnancy  or  by  pathological  processes. 

The  uterus,  especially  the  body,  is  very  movable,  so  that,  if  the  cervix 
cannot  be  drawn  down  to  the  vaginal  outlet,  the  condition  is  abnormal 
and  the  cause  is  to  be  sought  for.  On  account  of  this  mobility  its  axis 
is  without  doubt  subject  to  considerable  variation  within  normal  limits. 
Normally  the  long  axis  of  the  uterus  is  directed  forward  (anteverted) , 
in  which  position  the  intra-abdominal  pressure  is  exerted  upon  the 
posterior  surface  of  the  body  of  the  uterus,  bending  it  forward  on  the 
cervix,  so  that  it  becomes  anteflexed  (according  to  Waldeyer,  from  70 
to  100  degrees).  According  to  the  last-named  author  the  external  os 
is  on  a  level  with  the  upper  end  of  the  symphysis,  in  a  transverse  ver- 
tical plane  passing  through  the  spines  of  the  ischia,  and  the  axis  of  the 
cervix  is  in  line  with  that  of  the  pelvis  at  this  point.  The  condition 
of  the  neighboring  intestinal  coils  may  also  affect  its  position.  As  the 
uterine  axis  forms  an  angle  with  that  of  the  vagina,  the  lower  end  of 
the  cervix,  including  the  anterior  and  posterior  lips  and  the  external 
os,  abuts  against  the  posterior  vaginal  wall. 

Fixation.— The  broad  or  lateral  ligaments  fasten  both  the  body  and 
the  cervix  to  the  lateral  walls  and  floor  of  the  pelvis.  The  body  is  also 
supported  by  the  round  ligaments  attached  to  its  cornua  and  so  directed 
as  to  hinder  its  posterior  or  lateral  displacement  and  to  some  extent 
its  downward  prolapse.  The  other  ligaments  of  the  uterus,  both  true 
(uterosacral)  and  false  (anterior  and  posterior),  steady  the  cervix  fore 
and  aft.  In  addition  the  cervix  is  fixed  by  its  attachment  to  the  bladder 
and  vagina  so  that  it  is  the  most  fixed  part  of  the  uterus.  As  the  origins 
and  insertions  of  the  round  ligaments  are  approximately  in  the  same 
horizontal  plane,  in  the  erect  position,  they  offer  little  resistance  to  the 
descent  or  prolapse  of  the  uterus,  even  when  they  are  not  relaxed,  until 
it  reaches  a  lower  level  in  the  first  degree  of  prolapse,  when  they  become 
really  suspensory  and  oppose  further  descent.  Prolapse  is  prevented 
principally  by  the  support  afforded  by  atmospheric  pressure  acting  on 
the  intact  floor  of  the  pelvis.  The  integrity  of  this  floor,  especially  of 
the  levator  ani,  by  securing  a  tightly  closed  vaginal  outlet,  is  the  most 
important  factor  in  the  support  of  the  uterus.  If  the  vagina  becomes 
an  open,  air-containing  tube  from  relaxation  of  its  outlet,  due  to  perineal 
laceration,  the  support  of  atmospheric  pressure  on  the  pelvic  floor  is  lost, 
as  air  is  admitted  above  it,     When  the  uterus  becomes  enlarged  from 


PLATE  XLI 


FIG.   148 


URETER 
OBTURATOR 

ARTERY 


INTERNAL    ILIAC 

ARTERIES 
EXTERNAL    ILIAC 

ARTERY 
VESICO-VAGINAL 

ARTERY 


The  Female  Pelvis  and  Pelvic  Viscera  from  Above,  the  Uterus 
and  Adnexa  being  Drawn  Forward.     (Testut. ) 


THE  FEMALE  PELVIC  GENITAL  ORGANS  433 

pregnancy  or  otherwise  the  ligaments  stretch  or  lengthen  to  accommo- 
date themselves  to  the  new  conditions.  During  involution  of  the  uterus 
after  childbirth  the  ligaments  again  contract  and  shorten,  but  if  the  uterus 
remains  large  and  heavy  (subinvoluted),  or  the  patient  gets  up  too  soon, 
and  especially  if  she  strains  herself  by  work  before  the  balance  between 
the  uterus  and  its  ligament  is  reestablished,  there  is  danger  of  uterine 
displacement,  as  it  is  not  properly  supported. 

Displacements. — As  we  have  seen  the  cervix  is  the  most  fixed  part  of 
the  uterus,  while  the  ligaments  holding  the  body  allow  it  more  freedom 
of  motion.  The  slightly  constricted  part  (isthmus),  where  the  more 
fixed  cervix  joins  the  heavier  and  more  movable  body,  is  an  exposed  and 
weak  point  where  ante-  and  retroflexions  occur,  the  body  of  the  uterus 
bending  on  the  cervix.  In  anteflexion  the  body  is  bent  forward  onto 
the  bladder,  and  we  can  palpate  it  by  combined  vaginal  and  abdominal 
palpation,  while  in  retroflexion  the  body  occupies  Douglas'  pouch  and 
presses  upon  the  rectum,  through  which  or  the  vagina  it  may  be  readily 
palpated.  A  certain  degree  of  anteflexion  is  not  pathological,  but  nor- 
mal; pathological  anteflexion  usually  causes  dysmenorrhea,  on  account 
of  the  sharp  bend  in  the  canal. 

If  the  uterus  is  anteverted  or  retro  verted  it  seesaws  on  the  isthmus  as  a 
transverse  axis,  so  that  if  the  body  moves  in  one  direction  the  cervix  tilts 
in  the  opposite  direction.  Thus  in  anteversion  the  body  lies  upon  the 
bladder,  while  the  vaginal  portion  of  the  cervix  tilts  up  and  back  into  the 
posterior  vaginal  fornix;  in  retroversion  the  cervix,  tilted  forward,  presses 
against  the  bladder,  while  the  body  of  the  uterus  presses  against  the 
rectum.  Ineitherof  these  cases  it  may  be  difficult  to  make  the  external 
os  present  at  the  end  of  a  speculum. 

Any  of  these  malpositions  may  tend  to  prevent  conception,  by  reason 
of  the  position  of  the  os  or  the  obstruction  due  to  the  sharply  bent 
canal.  Anteversion  is  said  to  be  more  common  among  childless  women, 
retroversion  among  women  who  have  borne  children,  especially  if  after 
labor  they  have  been  bandaged  too  tightly  and  too  long  in  the  supine 
position.     The  retrodisplaced  uterus  also  drags  back  the  appendages. 

A-  the  round  ligaments  prevent  backward  displacement  of  the  uterus, 
their  relaxation  allows  of  retroversion,  and  their  shortening  produces 
anteversion,  which  may  also  be  caused  by  the  retraction  of  the  utero- 
sacral  Ligaments,  by  pulling  the  cervix  backward  and  thus  tilting  the  body 
forward.  In  anteversion  or  anteflexion  the  body  of  the  uterus  may  so 
upon  the  bladder  as  to  cause  some  {irritability.  In  retroversion 
the  cervi*  presses  upon  the  bladder  near  its  outlet  so  as  to  cause  more 
irritability  of  the  bladder  than  the  pressure  of  the  antenexed  or  ante- 
verted uterus  upon  its  less  sensitive  upper  part.  In  the  same  manner 
the  body  in    retroversion   or  retroflexion   and    the  cervix  in  anteversion 

upon  th<-  rectum  &s  to  cause  rectal  tenesmus  and  difficult 

and  painful  defecation,  and  thereby  induce  constipation. 

The  litems  displaced  in  any  of  the  above  ways  may  regain  its  normal 

DO  itioil  Unlee    adhesions  OCCUr  and  fasten  it  to  the  WSCUS,  against  which 
it    presses,    whereby    the    symptom  -;    due    to    pressure    become    chronic. 
28 


434  PELVIS  AND  PERINEUM 

Either  form  of  flexion  may  cause  dysmenorrhea  by  obstructing  the 
escape  of  the  menstrual  flow.  When  the  supporting  ligaments  are 
relaxed  and  this  condition  is  combined  with  a  weakening  of  the  support 
of  the  perineum,  following  its  rupture,  and  an  abnormally  heavy  uterus, 
the  latter  may  sink  or  become  prolapsed  so  as  to  present  at  the  vulva 
or  even  to  lie  partly  or  wholly  outside  the  vulva.  The  first  degree  of 
prolapse  must  be  associated  with  some  posterior  displacement,  so  that 
the  uterine  axis  may  become  parallel  to  the  vaginal.  Therefore  the 
normal  intra-abdominal  pressure  which  helps  to  maintain  normal  ante- 
flexion tends  to  prevent  prolapse.  A  much  rarer  condition,  and  one  more 
difficult  to  treat,  is  where  the  uterus  is  inverted  or  turned  inside  out. 
This  may  be  due  to  the  traction  of  a  polypoid  submucous  fibroid. 
The  normal  uterus  is  so  mobile  that  the  cervix  may  readily  be  drawn 
down  by  a  tenaculum  to  the  vaginal  orifice  in  operations  which  con- 
cern the  cervix.  In  fact,  if  the  uterus  is  found  not  readily  movable,  some 
pathological  cause  should  be  sought  for.  Lateral  version,  usually  of 
the  fundus  to  the  left  and  of  the  cervix  to  the  right  (Merkel,  Waldeyer) 
is  very  common  and  not  pathological  unless  excessive  or  fixed. 

Relations. — As  the  rectum  lies  behind  it,  we  can  examine  the  uterus, 
to  determine  its  size  and  position,  by  palpation  through  the  rectum 
almost  if  not  quite  as  well  as  through  the  vagina,  especially  if  there  is 
retroflexion  or  retroversion. 

Between  the  uterine  body,  the  supravaginal  portion  of  the  cervix,  and 
the  upper  2  to  2.5  cm.  (f  to  1  in.)  of  the  posterior  vaginal  wall  in  front 
and  the  rectum  behind  lies  the  recto-uterine  pouch  of  peritoneum,  or  the 
pouch  of  Douglas.  The  latter  is  strictly  the  lower  part  of  the  pouch,  which 
lies  below  the  laterally  placed  crescentic  folds  of  the  posterior  false  liga- 
ments of  the  uterus,  enclosing  the  uterosacral  ligaments.  Douglas'  pouch 
normally  contains  the  rectum,  coils  of  small  intestine,  and  part  of  the 
sigmoid  loop.  It  is  readily  examined  by  the  finger  per  rectum  or  per 
vaginam,  or  opened  into  through  the  posterior  vaginal  fornix,  or  drained 
through  such  an  opening  if  occupied  by  an  abscess.  The  peritoneum  is 
reflected  from  the  front  of  the  isthmus  onto  the  bladder  to  form  the 
shallower  uterovesical  pouch.  This  contains  the  uterine  body  in  its  ante- 
flexed  position  and  perhaps  some  coils  of  intestine.  The  subperitoneal 
connective  tissue  continues  down  below  this  reflection  of  peritoneum  and 
separates  the  cervix  from  the  bladder,  allowing  the  separation  of  the  two 
along  this  plane  in  hysterectomy.  This  layer  is  continuous  with  that 
found  at  the  sides  of  the  cervix,  between  the  layers  of  the  broad  liga- 
ments, and  with  a  more  scanty  amount  beneath  the  peritoneum  covering 
the  back  of  the  supravaginal  portion  of  the  cervix.  The  cervix  is  thus 
seen  to  be  enclosed  in  a  layer  of  loose  connective  tissue  of  varying  thickness, 
continuous  with  the  subperitoneal  tissue.  This  facilitates  the  amputa- 
tion of  the  cervix  without  opening  the  peritoneal  cavity  (i.  e.,  extraperi- 
toneal). 

From  the  above  we  see  the  relation  of  the  uterus  to  the  peritoneum, 
which  covers  the  anterior  and  posterior  surfaces  and  the  upper  end  of 
the  body,  and  the  supravaginal  portion  of  the  posterior  part  of  the 


THE  FEMALE  PELVIC  GENITAL  ORGANS  435 

cervix.     It  is  reflected  from  the  sides  of  the  body  and  cervix  to  form 
the  broad  ligaments. 

Newgrowths,  like  carcinoma  of  the  uterus,  may  extend  onto  the  rectum 
or  bladder,  and  vice  versa,  and  the  ureters,  on  account  of  their  close 
relations  to  the  cervix,  may  become  occluded  by  the  extension  of  a 
carcinoma,  to  the  latter,  and  uremia  result. 

The  Cervix. — Of  the  three  zones  (Fig.  154)  into  which  the  cylindrical 
cervix  is  divided,  the  lower  or  intravaginal  zone  projects  into  the  upper 
part  of  the  vagina  at  such  an  angle  that  its  lower  end  abuts  against 
the  posterior  vaginal  wall.  This  lower  end  contains  the  external  os,  or 
lower  opening  of  the  uterine  canal,  bounded  by  a  lower  anterior  lip, 
short  and  thick,  and  a  posterior  lip,  which  is  longer  than  the  anterior 
by  reason  of  the  greater  height  of  the  posterior  vaginal  fornix.  The 
orifice,  a  transverse  fissure  about  6  mm.  broad  in  the  virgin,  becomes 
irregular  after  childbirth  owing  to  the  notching  of  its  lips,  so  that  by 
palpation  of  the  os  we  can  say  whether  a  woman  has  borne  children. 
This  intravaginal  portion  of  the  cervix  can  be  seen  through  the  speculum 
or  examined  by  the  finger  in  the  vagina,  and  is  more  exposed  to  lesions  of 
all  sorts  than  other  parts  of  the  cervix,  especially  to  "erosions"  and 
cancerous  ulcerations.  The  first  part  that  we  see  or  feel  on  examina- 
tion is  usually  the  anterior  lip. 

The  cervix  may  become  hypertrophied  so  as  to  be  elongated  and  pro- 
ject downward  into  the  vagina  unusually  far.  This  may  resemble  a  pro- 
lapse, but  if  we  try  to  push  it  up,  usually  an  easy  matter  in  prolapse, 
resistance  and  pain  are  at  once  met  with  from  the  tension  of  its  connec- 
tions. This  elongation  may  affect  either  the  intravaginal  or  supravaginal 
portion  of  the  cervix.  In  the  former  case  the  vaginal  fornices  are  deep- 
ened,  in  the  latter  they  are  not.  Such  a  cervix  may  even  interfere  with 
coitus,  and  a  conical,  pointed  cervix  is  unfavorable  to  conception  and 
may  be  a  cause  of  sterility.  Another  cause  of  sterility  as  well  as  of 
dysmenorrhea  is  furnished  by  an  atresia  or  narrowing  of  the  os  ex- 
ternum, by  no  means  rare.  The  cervix  may  be  enormously  enlarged 
from  cli conic  disease.  During  pregnancy  it  becomes  broad  and  soft 
and  is  drawn  up  from  the  cavity  of  the  vagina,  the  external  os  being 
occluded  by  a  plug  of  mucus.  The  intravaginal  portion,  relatively 
large  mihI  prominent  in  female  children,  may  nearly  completely  disap- 
pear in  old  women,  and  sometimes  in  younger  multipara.  It  possesses 
K)  little  sensation  that  we  can  insert  a  tenaculum  to  pull  it  down  and 
make  all  manner  of  applications  to  it  without  producing  much  if  any 
pain. 

The  zone  of  vaginal  attachment,  about  5  mm.  deep,  is  obliquely  placed, 
□ding  higher  behind   than   in   front,  thus  making  the  posterior  lip 
longer  and  the  posterior  vaginal  fornix  deeper. 

The  supravaginal  zone  represents  about  half  of  the  cervix  behind  and 
two-thirds  in  front.  It  is  connected,  as  we  have  seen  above,  with 
the   bladder  anteriorly,    while    posteriorly   it   is   covered    by    peritoneum 

and  enters  into  the  anterior  wall  of  Dottgku?  pouch.     Perhaps  the  most. 

important  relation-  of  the  cervix  are  found  at  its  sides  which  are  con- 


436 


PELVIS  AND  PERINEUM 


nected  with  the  broad  ligaments,  in  which  at  this  level  lie  the  uterine 
vessels  and  the  ureter.  The  uterine  artery  passes  nearly  horizontally 
inward  in  the  base  of  the  broad  ligament  to  the  supravaginal  portion 
of  the  cervix,  accompanied  by  the  large  uterine  veins,  arranged  in  a 
plexiform  manner. 

One  of  the  most  important  topographical  points  in  the  female  pelvis  is 
the  crossing  of  the  uterine  artery  in  front  of  the  ureter.  This  occurs  on 
a  level  with  the  intravaginal  portion  of  the  cervix  and  about  12  to  18  mm. 
(^  to  f  in.)  from  the  cervix.  The  ureter  passes  through  the  plexus 
of  the  uterine  veins.     The  fact  of  the  crossing  is  important,  for  it  occurs 


Fig.  149 
rectum   sacrum  uterus 


INT.   ILIAC  VEIN 


UTERINE  TUBE 
VENOUS   PLEXUS 


ACETABULUM 
LIG.  TERES 


VESICAL  PLEXUS 
URETER 
OBTURATOR  INTER- 
NUS  MUSCLE 


ISCHIO-RECTAL 
FOSSA 


SACRAL  PLEXUS 


UTERINE  ART. 


SUP.  VESICAL  ART. 


%T~ VESICAL  ORIFICE 


\,.'       VAGINAL   PORTION 
OF  UTERUS 


Frontal  section  of  female  pelvis,  showing  relations  of  ureter  to  uterus  and  its  vessels. 


close  to  where  we  tie  or  clamp  the  uterine  vessels  in  removing  the  uterus 
or  cervix.  Hence  there  is  danger  of  wounding  the  ureter,  a  danger  which 
is  real,  for  it  has  occurred  in  many  reported  cases.  After  crossing  behind 
the  uterine  arteries  the  two  ureters,  converging  slightly,  incline  somewhat 
forward  so  as  to  reach  the  front  of  the  sides  and  then  the  anterior  wall 
of  the  vagina. 

The  small  cavity  of  the  uterus  is  a  mere  fissure.  The  cavity  of  the 
body  is  triangular  in  shape,  with  an  opening  at  each  angle  into  the 
Fallopian  tubes  above  and  the  narrow  internal  os  below.  The  latter 
opening  is  at  the  upper  end  of  the  fusiform  cervical  canal,  which  ends 


PLATE  XLII 


FIG.  150 


TUBAL    VESSELS 


FALLOPIAN 
TUBE 


UTERINE 
VEINS 


VAGINAL    VENOUS    PLEXUS 


UTERINE    ARTERY 


SUPERIOR    VAGINAL 
ARTERIES 


OS    UTERI         VAGINA    CUT    OPEN     BEHIND 


Vessels  of  the  Uterus  and  its  Appendages,  rear  view.     (Testut.) 


THE  FEMALE  PELVIC  GENITAL  ORGANS  437 

below  in  a  transverse  fissure,  the  external  os.  The  narrowness  of  the  os 
internum  may  be  such  as  to  be  an  obstacle  to  the  menstrual  flow  and  a 
cause  of  dysmenorrhea.  In  old  age  it  becomes  still  more  contracted  and 
even  closed.  The  cervical  canal  may  be  gradually  yet  fairly  quickly 
dilated  so  as  to  allow  inspection  and  digital  examination  of  the  uterus 
and  even  the  enucleation  of  large  tumors.  The  mucous  membrane  of  the 
cervical  canal  secretes  a  viscid  alkaline  mucus,  and  pathologically  its 
mucous  glands  are  liable  to  become  vesicular,  when  they  are  sometimes 
known  as  ovula  Nabothi.  The  motion  of  the  cilia  of  the  uterine  mucosa 
is  downward  toward  the  os  externum.  The  length  of  the  uterine 
cavity  averages  about  5  cm.  (2  in.)  in  nullipara?  and  5.5  to  7  cm.  (2\  to 
2f  in.)  in  multipara?.  We  can  determine  the  length  by  the  uterine 
sound. 

As  there  is,  strictly  speaking,  no  cavity,  the  bulk  of  the  uterus  is 
made  up  of  its  thick  wall.  Apart  from  its  remarkably  thick  mucous  mem- 
brane, which  is  thickened  and  then  partly  cast  oft'  at  the  monthly  periods 
and  becomes  the  decidua  during  gestation,  this  thick  wall  consists  prin- 
cipally of  unstriped  muscle  fibers.  This  tissue,  arranged  in  three  im- 
perfect layers,  is  remarkable  for  its  hypertrophy  and  newgrowth  during 
pregnancy,  and  it  is  largely  by  its  contraction  that  the  fetus  is  expelled. 
The  muscle  tissue  of  the  uterus  is  continuous  with  that  of  the  utero- 
sacral,  round,  uteroovarian,  and  broad  ligaments,  and  that  of  the 
Fallopian  tubes,  vagina,  and  bladder. 

In  this  tissue  in  any  part  of  the  uterus,  but  more  often  in  the  body, 
develop  the  common  fibroids,  myomata  or  fibromyomata,  as  they  are 
variously  called.  These  may  be  single  or  more  often  multiple,  and 
may  attain  a  very  large  size;  one  of  one  hundred  and  forty  pounds  has 
been  recorded,  but,  as  a  rule,  they  do  not  attain  the  size  of  the  largest 
ovarian  tumors.  In  their  evolution  they  often  acquire  a  partial  or  a 
complete  capsule  and  may  protrude  on  the  surface  {subperitoneal  variety), 
or  into  the  cavity  {submucous  variety),  or  they  may  remain  within 
the  walls  I  interstitial  variety).  They  occur  during  menstrual  activity, 
they  tend  to  atrophy  or  degenerate  after  the  menopause,  and  Sometimes 
become  involuted  with  the  rest  of  the  uterus  after  parturition.  They 
M€  particularly  common  among  negroes.  The  submucous  variety  is 
apt  to  cause  seven;  bleeding,  and  hence  should  be  removed  early.  The 
subserous  variety  is  liable  to  adhesions  from  local  peritonitis.  They 
may  prevent  conception,  cause  miscarriage,  or  complicate  parturition, 
according  to  their  size  and  situation. 

The  uterus,  enlarged  from  pregnancy  or  other  cause,  may  press  upon 
the  iliac  veins,  causing  hemorrhoids  or  varicose  veins  of  the  legs;  on 

the  lumbar  or  saeral  nerves,  causing  neuralgia  and  cramps;  or  on  the 
renal  veins  or  kidneys,  causing  albuminuria,  etc. 

Owing  to  its  small  size,  its  great  mobility,  and  the  protection  afforded 
by  the  pelvis,  the  unimpregnated  uterus  is  rarely  wounded.  The  prcg- 
ndiii  uterus  may  be  nvptiured  by  violence  or  by  its  own  contraction 
during  labor,  especially  it'  the  passage  of  the  fetus  is  obstructed.    The 

rupture   \-,  usually   near  the  junction  of  the  eervix   with   the  body. 


438  PELVIS  AND  PERINEUM 

Vessels. — The  uterus  is  supplied  by  the  uterine  arteries  from  the 
internal  iliac  and  the  ovarian  from  the  abdominal  aorta.  The  uterine 
artery  of  either  side,  passing  nearly  horizontally  inward  in  the  base  of  the 
broad  ligament,  crosses  in  front  of  the  ureter  (see  p.  436)  and  reaches 
the  side  of  the  supravaginal  portion  of  the  cervix,  whence  it  runs  up 
along  the  side  of  the  uterus,  between  the  folds  of  the  broad  ligament. 
At  the  cornu  or  angle  it  anastomoses  freely  with  the  ovarian  artery.  In 
young  individuals  the  artery  lies  0.5  to  1  cm.  Q-  to  -§-  in.)  from  the  uterus 
and  still  further  removed  from  the  cervix  and  the  lower  part  of  the  body. 
After  repeated  pregnancies  it  comes  to  lie  nearer  the  uterus  and  becomes 
more  tortuous,  so  that  in  operations  it  is  more  difficult  to  separate  the 
artery  from  the  uterus. 

At  the  uterine  end  of  the  round  ligament  the  small  funicular  artery, 
accompanying  the  round  ligament,  anastomoses  with  the  uterine  and 
ovarian  arteries.  Numerous  transverse  branches  from  the  uterine 
arteries  supply  the  uterus  and  anastomose  across  the  median  line.  Ow- 
ing to  this  fact  and  the  free  anastomosis  with  the  ovarian  artery,  a  ligature 
may  be  placed  around  the  uterus  without  affecting  the  circulation  above 
or  below. 

By  a  lateral  incision  into  the  upper  end  of  the  vagina,  opening  into 
the  base  of  the  broad  ligaments,  the  uterine  arteries  may  be  pulled 
down  and  tied,  the  relation  of  the  artery  to  the  ureter  being  carefully 
borne  in  mind,  as  it  should  be  also  in  securing  and  dividing  the  artery 
in  hysterectomy.  The  veins  form  large  plexuses  and  accompany  the 
corresponding  arteries. 

Lymphatics. — The  lymphatic  plexuses  of  the  cervix  and  body  are  con- 
tinuous. The  collecting  trunks  from  the  cervix  enter  the  external  and 
internal  iliac  and  the  lateral  sacral  nodes  and  those  below  the  bifurcation 
of  the  aorta.  Those  from  the  body  accompany  the  ovarian  vessels  and 
enter  the  lumbar  nodes  along  the  aorta. 

Development. — The  uterus  and  vagina  are  formed  by  the  fusion  of 
the  lower  ends  of  the  two  ducts  of  Muller,  the  two  ununited  upper  ends 
of  which  form  the  Fallopian  tubes.  The  bicorned  and  double  uteri 
are  due  to  the  failures  of  this  fusion  in  whole  or  in  part,  and  they  may 
be  associated  with  a  partial  or  complete  septum  dividing  the  vagina. 
Pregnancy  as  well  as  many  of  the  pathological  conditions  may  be  con- 
fined to  one-half  or  one  cornu  of  a  malformed  uterus. 

The  uterus  is  reached  for  operation  through  a  median  celiotomy  or 
through  the  vagina.  In  its  removal  (hysterectomy)  its  connections  with 
the  broad  ligaments,  vagina,  and  bladder  are  the  principal  things  to  be 
divided  or  separated.  Remember  that  its  two  arteries  reach  it  through 
the  broad  ligament,  the  ovarian  at  its  cornu,  the  uterine  opposite  the 
cervix.  We  repeat  again  that  the  relation  of  the  ureters  to  the  cervix 
and  the  uterine  vessels  must  be  borne  in  mind. 

The  Ovary. — The  ovary  is  a  paired  organ,  shaped  like  a  broad  almond, 
whose  length  averages  3.7  cm.  (1£  in.),  breadth  18  mm.  (f  in.),  thickness 
12  mm.  (|  in.).  Its  weight  is  about  7  gm.  (^  oz.)  in  the  adult,  the  right 
being  usually  a  little  the  larger.  Before  puberty  it  is  small,  it  enlarges 
about  puberty,  and  after  the  menopause  atrophies  very  much. 


THE  FEMALE  PELVIC  GESITAL  ORGANS 


439 


Position. — We  may  describe  a  typical  position  of  the  ovary,  remem- 
bering that,  being  a  movable  body,  it  may  temporarily  occupy  other 
positions  without  causing  any  disturbance.  The  latter  positions  may 
more  readily  change  into  abnormal  positions  which  do  cause  functional 
disturbances. 

When  the  other  pelvic  organs  are  normal  and  there  have  not  been 
repeated  pregnancies,  the  typical  position  of  the  ovary  in  the  upright 
posture  is  with  its  long  axis  vertical,  its  attached  border  in  front  and 
slightly  external,  its  free  border  behind  and  slightly  internal,  toward 
the  rectum,  its  lateral  surface  against  the  lateral  pelvic  wall  in  the  fossa 
ovarica,  and  its  mesial  surface  looking  into  the  pelvis. 


Fig.  151 
uterine  artery 


SUPERIOR   VESICAL 
ARTERY 


EXT.    ILIAC   ARTERY 


UMBILICAL  ARTERY 
OBTURATOR    FORAMEN 


"  I  mm  ovarica." 


The  fossa  ovarica,  or  the  depression  on  the  inner  surface  of  the  in- 
ternal obturator  muscle  in  which  the  ovary  lies,  varies  much  in  depth, 
;m<l  is  bounded  above  and  in  front  by  the  superior  vesical  artery,  behind 
by  the  ureter  and  uterine  artery,  below  and  in  front  by  the  lateral  attach- 
ment of  the  broad  Ligament.  Lodged  in  this  fossa  the  lateral  surface 
of  the  ovary  is  not  visible,  and  the  attached  border,  upper  end,  and  a 
variable  amount  of  tin-  free  border  and  mesial  surface  are  covered  by 
the  Fallopian  tube,  so  that  but  little  of  the  ovary  may  be  visible  on  inspect- 
ing the  pelvis. 

The  two  ovaries  are  seldom  entirely  symmetrical  in  position,  one  being 
lii^lif-r  or  more  ant-rior  than  the  other,  and,  if  the  uterus  is  deflected 


440  PELVIS  AND  PERINEUM 

to  one  side  (according  to  His,  to  the  left  side  in  the  proportion  of  three 
to  two),  the  ovary  on  the  opposite  side  is  more  exposed  by  the  tube  being 
somewhat  drawn  away  from  it,  and  its  somewhat  pointed  lower  pole 
may  be  drawn  mesially.  In  the  supine  position  the  ovary  lies  with  its 
long  axis  horizontal.  The  changing  relations  of  the  contiguous  viscera 
also  probably  affect  its  position. 

The  ovary  may  be  displaced  into  Douglas'  sac  or  even  into  the  utero- 
vesical  pouch.  Prolapse  of  the  ovary  is  favored  by  its  increased  weight 
and  the  relaxation  of  its  ligaments  in  subinvolution.  The  left  ovary  is 
prolapsed  more  frequently,  for  the  arrangement  of  its  veins  favors  venous 
congestion,  analogous  to  left-sided  varicocele  in  the  male  (p.  474),  and 
it  is  said  to  enlarge  more  during  pregnancy.  It  may  be  found,  especially 
in  childhood,  in  an  inguinal  or  femoral  hernia,  where  it  is  liable  to  strangu- 
lation, and  it  may  become  fixed  in  its  abnormal  position  by  adhesions. 
In  pregnancy  the  position  of  the  ovary  is  normally  altered.  When 
enlarged  the  ovaries  may  be  felt  through  the  vagina,  or  even  better  through 
the  rectum.  Their  position  is  indicated  on  the  surface  by  a  point  about 
5  cm.  (2  in.)  internal  to  the  anterior  superior  iliac  spine  and  in  a  sagittal 
plane  midway  between  the  latter  spine  and  the  symphysis.  A  frontal 
plane  at  the  promontory  of  the  sacrum  touches  or  lies  just  behind  the 
ovaries.  The  position  of  the  ovary  corresponds  to  the  middle  of  the 
upper  margin  of  the  acetabulum.  In  seeking  for  them  when  the  abdo- 
men is  opened,  the  hand  is  passed  along  the  back  of  the  broad  ligament 
from  the  uterus  outward. 

The  ovary  is  supported  and  held  somewhat  loosely  in  position  by  the 
attachment  of  the  tuboovarian  ligament  (fimbria  ovarica)  to  its  upper 
end  and  of  the  uteroovarian  ligament  to  its  lower  end;  by  its  meso- 
varium,  a  short  fold  covered  on  both  sides  by  peritoneum  from  the 
posterior  layer  of  the  broad  ligament,  from  which  it  projects  backward; 
and  by  the  ligamentum  infundibulopelvicum,  a  flbromuscular  band, 
containing  the  ovarian  vessels,  which  is  invested  by  a  fold  of  the  broad 
ligament  and  which  passes  from  the  side  of  the  pelvis,  above  and  in  front 
of  the  ovary,  to  the  upper  end  of  its  attached  border  where  the  vessels 
enter  the  hilum,  between  the  layers  of  the  mesovarium.  This  "liga- 
ment" forms  part  of  the  pedicle  in  the  removal  of  the  ovary  or  ovarian 
tumors. 

We  have  named  the  most  important  relations  of  the  ovary.  The  ureter, 
with  the  uterine  artery  in  front  of  it,  lies  behind  the  ovary.  External 
to  the  ovary,  in  the  fossa  ovarica,  are  the  obturator  vessels  and  nerve. 
Internal  to  the  ovary,  in  addition  to  the  Fallopian  tube,  are  coils  of  in- 
testine. 

Structure. — The  ovary  receives  from  the  posterior  layer  of  the  broad 
ligament  an  external  covering,  which  differs  from  the  serous  membrane 
of  the  latter  in  being  covered  by  columnar  epithelium.  Many  of  the 
ovarian  cysts  take  origin  in  this  epithelium.  The  surface  is  smooth 
before  puberty  and  more  and  more  scarred  during  menstrual  activity. 
The  scars  represent  where  ovisacs  have  ruptured,  and  the  larger  ones 
in  multipara  the  position  of  a  true  corpus  luteum  which  forms  when 


PLATE  XLIII 


FIG.   152 


Female  Pelvic  Viscera  from  Above.     (Gerrish,  after  Testut. ) 
'I  Ik-  ovary  and  tube  of  tli<-  lefl  lide  bave  been  lifted  ou1  i>r  place. 


TEE  FEMALE  PELVIC  GENITAL  ORGANS  441 

pregnancy  occurs.  Slight  extravasation  of  blood  follows  the  rupture 
of  an  ovisac  (or  Graafian  follicle),  but  when  a  vessel  of  unusual  size  is 
ruptured,  or  possibly  when  the  ovary  is  unduly  congested,  a  sudden 
copious  bleeding  may  occur  and  the  blood  collect  in  Douglas'  pouch  as 
a  pelvic  hematocele,  which  we  can  then  feel  as  a  doughy  tumor  by  vagi- 
nal or  rectal  examination. 

The  so-called  tunica  albuginea  is  a  thin  layer,  and  is  merely  a  con- 
densation of  the  ovarian  stroma.  Within  it  lies  the  cortex,  contain- 
ing numberless  Graafian  follicles  (ovisacs)  in  various  stages  of  develop- 
ment and  the  remains  of  some  that  have  burst  at  the  menstrual  periods. 
Some  ovarian  tumors  (cystic)  are  due  to  a  collection  of  fluid  in  a  dilated 
<  rraafian  follicle  (unilocular)  or  follicles  (multilocular).  The  ovisacs, 
as  they  ripen,  enlarge  and  approach  the  surface,  where  they  appear  as 
rounded  projections  when  ready  to  rupture  and  set  free  the  ovum. 

The  ovary  may  also  be  affected  by  malignant  newgrowths  and  by  der- 
moid cysts,  the  latter  due  to  an  island  of  epiblast  abnormally  included  in 
the  mesoblastic  ovarian  tissue.  Ovarian  cysts  or  tumors,  if  one  side  alone 
is  involved,  are  at  first  unilateral  in  position,  displacing  the  body  of  the 
uterus  to  the  opposite  side,  the  cervix  usually  to  the  same  side.  Later 
they  ascend  into  the  abdomen,  drawing  the  adnexa  attached  to  their 
pedicles  upward  with  them,  and  displacing  the  intestine  upward  so  as  to 
cause  dulness  on  percussion  over  them,  in  distinction  to  the  tympanitic 
note  we  obtain  in  ascites  from  the  bowel  floating  above  or  in  front  of 
the  fluid.  Strangulation  from  the  twisting  of  the  pedicles  of  ovarian 
cysts  is  not  uncommon,  especially  if  the  pedicle  is  long  and  the  cyst 
not  adherent. 

Development. — The  ovary,  developed  in  the  lumbar  region  like 
the  testis,  is  pulled  down  into  the  pelvis  in  a  similar  manner  by  the 
inguinal  ligament  of  the  primitive  kidney.  This  ligament,  attached 
to  the  uterus  and  the  inguinal  region,  remains  as  the  uteroovarian  liga- 
ment between  the  ovary  and  the  uterus,  and  the  round  ligament  between 
the  uterus  and  the  inguinal  region.  In  hernia  of  the  ovary  the  fibro- 
muscular  uteroovarian  ligament  draws  the  uterus  forward  and  to  the 
Bide  of  die  hernia,  a  fact  that  may  be  useful  in  diagnosis. 

The  upper  series  of  Wolffian  tubules  may  persist  as  a  small  pedun- 
culated cystic  sac,  the  hydatid  of  Morgagni  (appendix  vesiculosa),  at- 
tached t0  the  part  of  the  broad  ligament  forming  the  free  border  of  the 
mesosalpinx  and  adherent  to  the  fimbria  ovarica  or  one  of  the  other 
fimbria?  of  the  tube.  The  pa/roTXjHum  (organ  of  Rosenmtiller)  is  the 
atrophied  remains  of  the  middle  scries  of  the  Wolffian  tubules,  which 

in  the  male  form  the  epididymis.  This  lies  above  the  ovary  in  the 
mesosalpinx,  and  consists  of  several  vertical  tubes  joining  al  right  angles 
a  horizontal  tube,  a  segment  of  the  Wolffian  duel,  which  lies  above 

them.       The   Wolffian   duct   disappears    elsewhere,  as  a   rule,   but   may 

occasionally  persist  as  a  small  canal  in  the  broad  ligament  close  to  the 
uterus,  the  duet  of  Odriner,  which  is  lost  in  the  vaginal  wall  or  may 

open    near    the    urinary    meatus.      In    these    fetal    Structures,    especially 

the  parovarium,  develop  the  majority  of   the  unilocular  cysts  of  the 


442  PELVIS  AND  PERINEUM 

broad  ligament  (parovarian  cysts).  These  generally  contain  a  clear 
fluid. 

The  Fallopian  Tubes  (Oviducts). — These  trumpet-shaped  tubes,  about 
11.5  cm.  (4^  in.)  long,  are  structurally  continuous  with  the  uterus  at  its 
superior  angles,  from  which  they  pass  outward  to  the  sides  of  the  pelvis, 
where  they  are  closely  related  and  connected  with  the  ovaries.  They 
lie  between  the  two  layers  of  the  broad  ligaments,  along  their  upper 
free  margins,  so  that  the  serous  membrane  covers  three-fourths  of  their 
circumference  and,  being  reflected  off  inferiorly,  forms  the  mesosalpinx. 
The  lower  fourth  of  their  circumference  is  in  contact  with  the  subperi- 
toneal tissue  between  the  layers  of  the  broad  ligaments.  Thus  a  tubal 
pregnancy  or  a  fluid  collection  in  the  tube  (hydrosalpinx  or  pyosalpinx) 
when  it  ruptures  may  burst  into  the  peritoneal  cavity,  a  dangerous  course, 
or  between  the  layers  of  the  broad  ligament.  At  their  uterine  ends 
the  tubes  lie  between  and  slightly  above  the  round  ligament  in  front  and 
the  uteroovarian  ligament  behind. 

Course  and  Size. — At  the  outset  it  must  be  remembered  that  the  tube, 
lying  in  the  free  margin  of  the  broad  ligament  and  connected  with  two 
movable  viscera,  the  uterus  and  ovary,  must,  of  itself,  be  freely  movable  to 
correspond  to  the  changes  in  position  of  the  uterus  and  other  neighboring 
viscera.  The  narrow,  straight  inner  portion,  or  isthmus,  3  to  6  cm.  (1\  to 
2^  in.)  long,  passes  nearly  horizontally  outward  and  slightly  backward 
from  each  superior  angle  of  the  uterus  to  the  uterine  or  lower  end  of  the 
ovary  at  the  side  of  the  pelvis.  Thence  the  curved  and  dilated  portion,  or 
ampulla,  7  to  9  cm.  (2f  to  3^  in.)  long,  bends  sharply  upward  along  the 
mesial  aspect  of  the  attached  margin  of  the  ovary  to  its  upper  or  tubal  end, 
over  which  it  bends  backward  and  then  downward  along  the  free  border 
and  the  mesial  surface,  upon  which  rests  the  funnel-shaped  fimbriated 
extremity,  fringed  by  a  circle  or  circles  of  diverging  fimbriae  1  to  1.5  cm. 
(■§■  to  f-  in.)  long.  Thus  the  ovary  is  more  or  less  hidden  (see  Ovary, 
p.  439).  One  fimbria  longer  than  the  rest,  2.5  to  3.5  cm.  (1  to  1J  in.), 
and  attached  to  the  upper  end  of  the  ovary  (fimbria  ovarica),  constitutes 
the  tuboovarian  ligament. 

The  Fallopian  tube  forms  a  passageway  between  the  uterine  cavity 
(and  thus  the  surface  of  the  body)  and  the  peritoneal  cavity,  whereby 
the  ovum,  when  it  escapes  into  the  latter  by  the  rupture  of  the  ovisac, 
may  reach  the  uterus.  Hence  also  through  this  passageway  uterine 
or  vaginal  douches  and  microorganisms  may  reach  the  peritoneal  cavity 
and  cause  pelvic  and  perhaps  general  peritonitis. 

The  fimbrice  of  the  funnel-shaped  outer  end  of  the  ampulla  of  the 
tube  normally  so  embrace  the  ovary  that  they  conduct  the  ovum  into 
the  abdominal  opening  of  the  tube.  When  from  inflammation  these 
fimbriae  become  adherent  together,  or  to  neighboring  parts,  and  close 
the  opening  on  both  sides,  the  ova  cannot  escape  out  of  the  abdominal 
cavity,  and  sterility  results.  Again,  in  rare  instances,  when  the  adapta- 
tion of  the  fimbriae  is  imperfect,  an  ovum,  fecundated  by  spermatozoa 
which  have  passed  through  the  tube,  may  drop  back  and  develop  in  the 
peritoneal  cavity  as  one  form  of  extra-uterine  pregnancy. 


PLATE  XLIV 


FIG.  153 


Sagittal  Section  through  the  Ovary  and  Broad  Ligament. 

(Testut. ) 


1.    Broad  ligament. 
1'.    Anterior  surface. 
1".    Posterior  surface. 
_'.    Mesosalpinx. 

5.  Fallopian  tube. 

6.  Round  ligament. 

7.  Ovarv. 


7'.    Hilum  of  ovary  with  vessels 
entering  the  same. 

8.  Graafian  follicle. 

9.  Uterine  artery. 

10.  Uterine  veins. 

11.  Cellular  tissue  at  the  base  of 

the  broad  ligament. 

12.  1' refer. 


FIG.   154 


RECTAL    PERITONEUM 
ECTOVAGINAL    POUCH 

ERIOR  AND  POS- 
1IOR  LAYERS  OF 
OAD    LIGAMENT 

VESICAL 
ERITONEUM 

UTERO-VESICAL 
POUCH 

SUPRA-VAGINAL 
PORTION   OF 
CERVIX 


The   Cervix   Uteri    and   Upper  End   of   the  Vagina,  showing 
relations   to   the    peritoneum.      Diagrammatic.     (Gerrish, 
after  Testut.) 


THE  FEMALE  PELVIC  GENITAL  ORGANS  443 

The  mucous  membrane  which  lines  the  tube  is  arranged  in  longi- 
tudinal folds  and  lined  by  a  ciliated  epithelium  whose  movement  is 
toward  the  uterus,  thus  favoring  the  passage  of  the  ovum.  When 
from  inflammation  extending  from  the  uterus,  perhaps  of  gonorrheal 
origin,  the  tube  has  lost  its  epithelium,  the  descent  of  the  ovum  is  hindered 
and  the  ascent  of  spermatozoa  is  not,  thus  favoring  the  occurrence  of 
extra-uterine  pregnancy.  This  is  also  favored  by  any  cause  which 
hinders  the  descent  of  the  ovum  through  the  tube.  The  great  danger 
of  ectopic  gestation  is  the  hemorrhage  which  follows  rupture  of  the  tube, 
some  time  before  the  fourth  month.  If  the  rupture  is  to  be  intra- 
peritoneal, it  usually  occurs  earlier  than  extraperitoneal  rupture.  The 
lumen  of  the  tube  varies,  being  about  1  mm.  at  the  uterine  aperture, 
3  mm.  in  the  isthmus,  8  mm.  in  the  ampulla,  and  2  to  3  mm.  at  the 
abdominal  aperture.  Ciliated  epithelium  extends  along  the  inner  surface 
of  the  fimbriae  and  gradually  merges  into  the  endothelium  of  the  peri- 
toneum on  their  outer  surface.  The  fimbriated  extremities  furnish  the 
only  instance  where  serous  and  mucous  membranes  adjoin  one  another. 

As  the  result  of  inflammation,  usually  due  to  gonorrhea  or  sepsis 
following  abortion,  the  tube  may  be  closed,  especially  at  its  narrow 
points,  the  two  extremities,  first  at  the  outer,  later  at  the  inner,  so  that 
the  products  of  inflammation  are  pent  up  within  the  tube,  which  becomes 
distended  to  the  size  of  the  intestine  (hydro-  or  pyosalpinx,  pus  tube). 
Such  a  pus  tube  may  leak  a  little  from  time  to  time.  If  this  leakage 
occurs  into  the  peritoneal  cavity  recurrent  attacks  of  pelvic  peritonitis 
are  produced.  In  chronic  pus  tubes,  however,  the  pus  is  sterile  in  a 
large  percentage  of  cases.  The  peritoneum  on  the  surface  of  pus  tubes 
is  apt  to  contract  adhesions  to  neighboring  parts.  The  closure  of  the 
lumen  of  the  tubes  also  causes  sterility.  The  tubes  are  the  most  frequent 
seat  of  genital  tuberculosis  and  the  most  frequent  source  of  infection 
in  peritoneal  tuberculosis  in  the  female.  The  proximity  of  the  right 
tube  to  the  appendix  should  be  remembered,  for  it  accounts  for  many 
mistakes  in  diagnosis,  a  right  salpingitis  being  mistaken  for  appendicitis, 
and  vice  versa. 

A  tufje  enlarged  by  tubal  pregnancy  or  from  hydro-  or  pyosalpin- 
gitis  may  be  felt  by  vaginal  or  rectal  examination.  They  may  be 
reached  for  operation  (1)  by  (lie  vaginal  route,  (a)  laterally  between  the 
layers  of  tin-  broad  ligament,  and  therefore  exi raperitoneally,  (6) 
posteriorly  through  Douglas'  pouch,  as  iu  vaginal  hysterectomy;  (2) 
through  an  abdominal  incision. 

I'  boukl  !)'•  remembered  in  operations  that  the  fimbriated  extremity 
may  be  in  close  relation  with  the  ureter,  a  matter  of  importance  if  ad- 
hesion exist. 

The  tubal  hlooil  supply  is  from  a  branch  of  the  ovarian  artery  run- 
ning along  it-,  lower  bolder  in  the  broad  ligament  which  Forms  its  meso- 
salpinx. 

In  their  development  the   Fallopian  tubes  represent   the  upper  ex- 
tremities or  ununited  parts  of  the  duets  of  Muller;  hence  morphologically 
rell  as  itructurally  they  are  continuous  with  the  cornua  of  the  uterus. 


444  PELVIS  AND  PERINEUM 

The  Broad  Ligaments. — These  ligaments,  also  called  lateral  liga- 
ments, from  their  position  on  either  side  of  the  uterus,  form,  as  it 
were,  a  common  mesentery  for  the  uterus  and  its  adnexa,  especially  the 
Fallopian  tubes.  They  consist  essentially  of  the  two  layers  of  peritoneum 
which,  after  covering  the  anterior  and  posterior  surfaces  of  the  uterus 
as  described  (p.  434),  are  reflected  from  the  sides  of  the  latter  to  the  sides 
and  floor  of  the  pelvis,  where  they  become  continuous  with  the  parietal 
peritoneum. 

In  addition  to  the  Fallopian  tube,  ovary,  round  ligament,  and  fetal 
relics,  the  broad  ligament  of  each  side  contains  between  its  folds  the 
uteroovarian  ligament,  the  uterine,  ovarian,  and  funicular  vessels,  the 
corresponding  lymphatics,  the  uterine  plexus  of  nerves,  unstriped  muscle 
tissue  continuous  with  the  uterus  mesially,  and  loose  adipose  cellular 
tissue  continuous  with  the  subperitoneal  tissue  of  the  pelvis  and  sometimes 
called  the  parametrium.  In  this  tissue,  at  the  base  of  the  ligament,  lies 
the  ureter  in  relation  with  the  uterine  vessels  (see  p.  436).  Inflammation 
of  this  tissue  (parametritis,  if  near  the  sides  of  the  uterus)  is  the  com- 
monest form  of  pelvic  cellulitis  in  women,  is  often  puerperal  in  origin, 
and  results  in  abscess  in  a  minority  of  cases.  Such  an  abscess  may  be 
opened  through  the  lateral  fornix  of  the  vagina.  The  infection  may 
spread  from  an  inflammation  of  the  small  amount  of  similar  tissue  sepa- 
rating the  muscular  and  peritoneal  coats  of  the  uterus  (perimetritis),  and 
it  may  extend  to  the  similar  tissue  beneath  the  parietal  peritoneum  of 
the  pelvis,  or  pass  over  the  pelvic  brim  into  the  iliac  fossa,  where  it  often 
points  just  above  Poupart's  ligament  (see  p.  308). 

The  muscular  tissue  ensheaths  the  vessels  and  is  of  especial  importance 
in  serving  as  a  support  to  the  uterus  and  in  helping  to  keep  it  in  place. 
When  the  uterus  enlarges  during  pregnancy  it  fills  the  space  between 
the  folds  of  the  broad  ligaments  so  that  the  latter  nearly  disappear,  to 
reappear  with  the  involution  of  the  uterus.  Hence  for  a  time  after 
parturition  they  are  lax  and  offer  but  feeble  resistance  to  uterine  dis- 
placements, a  reason  for  not  allowing  a  woman  to  get  up  too  soon  after 
confinement. 

Each  broad  ligament  represents  a  quadrilateral  plate  which,  with  the 
uterus,  divides  the  pelvis  into  an  anterior  (utero vesical)  and  a  posterior 
(uterorectal)  fossa.  The  inner  or  mesial  border  of  the  broad  ligament 
represents  its  attachments  to  the  sides  of  the  uterus  and  the  upper  end  of 
the  vagina.  In  this  border  the  uterine  vessels  pass  up  along  the  sides 
of  the  uterus.  As  the  posterior  fold  passes  onto  the  posterior  surface 
of  the  upper  end  of  the  vagina  we  can  understand  how  an  incision  in 
the  lateral  wall  of  this  part  of  the  vagina  will  open  into  the  space  be- 
tween the  two  layers  of  the  ligament  at  its  base,  and  how  we  can  pal- 
pate through  the  vagina  any  tumor  or  swelling  situated  here.  The 
base  or  lower  border  of  the  broad  ligaments  rests  upon  the  floor  of  the 
pelvis,  formed  by  the  levator  ani  and  covered  by  the  rectovesical  fascia. 
The  abundant  areolar  tissue  here  gives  passage  to  the  uterine  vessels 
and  nerves  and  the  ureter,  which  pass  from  behind  and  external  forward 
and  inward.     Here,  as  well  as  along  its  lateral  border,  its  layers  become 


THE  FEMALE  PELVIC  GENITAL  ORGANS  445 

continuous  with  the  parietal  peritoneum  of  the  pelvis.  Owing  to  the 
slant  of  the  pelvic  cavity,  the  anterior  layer  is  reflected  at  a  higher  level 
than  the  posterior,  so  that  the  latter  is  deeper  or  longer  than  the  former. 
It  is  also  more  important  on  account  of  its  direct  relation  with  the  ovary. 

Its  lateral  borders  transmit  the  ovarian  vessels  and  the  round  ligaments 
and  meet  the  sides  of  the  pelvis,  lined  by  the  obturator  interims  muscle 
and  fascia.  The  two  layers  are  continuous  along  the  free  upper  border  of 
the  broad  ligament,  which  contains  the  Fallopian  tube,  so  that  the  upper 
part  of  the  ligament  forms  the  mesentery  of  the  tube  (mesosalpinx). 
But  the  tube  does  not  extend  to  the  lateral  limits  of  the  broad  ligament. 
The  outer  part  of  the  free  upper  margin  of  the  ligament,  beyond  the 
fimbriated  extremity  of  the  tube,  is  at  a  lower  level  than  the  mesial 
portion  (mesosalpinx)  and  contains  the  ovarian  vessels  as  they  pass  from 
the  sides  of  the  pelvis  to  the  ovary,  enclosed  in  a  band  of  fibromtiscular 
tissue,  called  the  infundibulopelvic  ligament,  since  it  extends  between 
the  infundibulum  (fimbriated  extremity  of  the  tube)  and  the  side  of 
the  pelvis.  Together  with  a  portion  of  the  broad  ligament,  the  Fallopian 
tube,  and  the  uteroovarian  ligament  it  constitutes  the  pedicle  of  an 
ovarian  tumor.  Below  the  vessels  is  a  thin,  clear  space  through  which 
a  ligature  may  be  passed  and  tied  over  the  top  of  the  ligament  to  control 
the  ovarian  vessels. 

The  upper  part  of  the  broad  ligament  which  forms  the  mesosalpinx 
is  thin,  translucent,  devoid  of  muscular  tissue,  and  contains  the  fetal 
relics  and  the  tuboovarian  vessels.  Projecting  from  and  attached  to  the 
posterior  layer  is  the  ovary.  More  mesially  the  recto-uterine  or  posterior 
ligaments  of  the  uterus  are  continuous  with  this  same  layer.  Between 
the  folds  of  the  broad  ligament  are  found  unilocular  cystic  tumors  (usually 
originating  from  fetal  relics),  hematocele,  abscess,  and  tumors  (intra- 
ligamentous), of  which  the  cystic  tumors  are  perhaps  the  most  common. 
These  may  all  be  palpated  through  the  vagina  and  reached  for  operation 
by  means  of  a  vaginal  or  abdominal  incision.  Unlike  many  ovarian 
tumors,  they  are  commonly  sessile  and  rarely,  if  ever,  pedunculated. 
We  are  accustomed  to  think  of  the  broad  ligaments  as  vertical,  and  as 
such  to  describe  them,  but  when  we  consider  the  normal  anteflexed 
position  of  the  uterus  we  find  that  the  greater  part,  except  the  base, 
of  the  uterine  end  of  the  ligament  is  more  horizontal  than  vertical. 

The  Round  Ligaments. — These  two  rounded  cords  of  unstriped 
muscle,  fibrous  and  elastic  tissue,  about  12.5  cm.  (5  in.)  in  length,  com- 
mence  at  the  upper  lateral  angles  of  the  uterus  just  below  and  in  front 
of  the  Fallopian  tubes,  where  tlxy  are  continuous  with  the  superficial 
uterine  fibers.  Each  passes  at  first  outward  and  downward  toward  the 
e  of  the  broad  ligament;  then  nearly  horizontally  outward  near 
the  base  of  the  ligament  and  beneath  its  anterior  layer,  in  front  of  die 
ureter  and  tli*-  uterine  vessels;  thence  upward,  outward,  and  forward 
r  the  pelvic  brim  and  fli<'  lower  end  of  the  iliac  fossa  to  the  infernal 
abdominal  ring.  In  die  latter  part  of  its  course  if  corresponds  to  that 
of  die  vas  deferens,  and  crosses,  like  die  hitter,  the  obturator  and  external 
iliac  vt   el    and  the  unobliterated  portion  of  the  hypogastric  artery 


446  PELVIS  AND  PERINEUM 

(i.  e.,  superior  vesical  artery).  It  finally  loops  around  the  outer  side  of 
the  curve  of  the  deep  epigastric  artery  to  enter  the  inguinal  canal.  In 
this  part  of  its  course  also  it  not  infrequently  projects  so  far  forward  as 
to  form  a  kind  of  short  mesentery.  In  passing  through  the  inguinal 
canal  it  receives  a  covering  from  the  layers  of  the  abdominal  wall  like  the 
spermatic  cord,  but  the  striped  fibers  derived  from  the  internal  oblique 
(cremaster)  are  mostly  attached  to  the  pillars  of  the  ring  and  the  pubic 
spine.  It  may  be  accompanied  by  a  process  of  peritoneum,  the  canal  of 
Nuck,  which  corresponds  to  the  processus  vaginalis  in  the  male  and  occurs 
as  a  sac-like  pouch  above  and  in  front  of  the  round  ligament,  not  as  a 
hollow  tube  around  it,  as  is  sometimes  described.  This  serous  pouch  is 
constant  in  the  fetus,  occurs  in  children  in  20  per  cent,  of  cases  (Zucker- 
kandl),  and  in  isolated  cases  may  persist  even  to  adult  life.  But  usually 
it  is  only  represented  by  a  funnel-shaped  depression  at  the  internal  ring. 

When  present  it  predisposes  to  inguinal  hernia,  or  if  it  becomes  con- 
stricted the  distal  portion  may  form  the  sac  of  a  "cyst  of  the  canal  of 
Nuck,"  analogous  to  an  encysted  hydrocele  of  the  cord  in  the  male. 

After  leaving  the  external  ring,  which  in  the  female  is  smaller  than 
in  the  male  and  lies  just  external  to  and  a  little  above  the  pubic  spine, 
the  round  ligament  expands  fan-like  to  be  attached  to  the  connective 
tissue  of  the  labium  majus  and  the  periosteum  over  the  pubic  spine. 

When  the  uterus  is  in  its  typical  position,  the  round  ligaments  are 
not  taut,  but  only  when  there  is  backward  displacement  or  a  prolapse, 
hence  they  play  but  a  secondary  role  in  supporting  the  uterus.  Con- 
traction or  preternatural  shortness  of  the  ligaments  is  said  to  be  a  cause 
of  anterior  displacement  of  the  uterus. 

For  downward  or  backward  displacements  Alexander's  operation  of 
shortening  the  ligaments,  and  thereby  pulling  the  uterus  forward  and, 
if  prolapsed,  upward,  has  often  been  performed.  The  incision  is  like 
that  for  inguinal  hernia. 

Sometimes  there  is  difficulty  in  finding  the  ligament,  and  for  this  pur- 
pose the  external  ring  is  exposed  and  the  tissues  below  and  internal  to 
it  are  hooked  up  and  pulled  upon,  or  the  canal  is  slit  up  for  a  distance 
and  the  contents  of  the  canal  similarly  dealt  with.  We  may  pull  down 
and  shorten  the  ligament  by  as  much  as  10  cm.  (4  in.)  in  some  cases. 
After  pulling  down  the  cord  for  a  certain  distance  a  pouch  of  peritoneum 
is  apt  to  appear  at  the  external  ring.  This  may  represent  the  canal  of 
Nuck,  but  almost  always  a  new  pouch  pulled  down  from  the  peritoneum 
at  the  internal  ring.  Such  a  pouch  occupying  the  canal  naturally  pre- 
disposes to  hernia  and  the  latter  has  not  infrequently  followed  such 
operations,  hence  a  Bassini  operation  should  be  performed  in  such 
cases. 

The  round  ligament  is  stronger  than  one  would  suppose,  and  bears  a 
very  considerable  traction  (0.5  to  0.6  kgr.,  according  to  different  obser- 
vers). In  pregnancy  it  becomes  four  times  as  stout  as  in  the  non-pregnant 
state. 

Its  artery,  the  funicular,  is  derived  like  that  of  the  vas  deferens  from 
the  superior  vesical  (i.  e.,  hypogastric),  as  the  ligament  crosses  the  latter. 


THE  FEMALE  PELVIC  GENITAL  ORGANS  447 

It  anastomoses  with  the  uterine  and  ovarian  at  the  uterine  end  and  with 
the  external  pudic  in  the  labium. 

The  Vagina. — This  musculomembranous  passageway  between  the 
vestibule  and  the  uterus  is  directed  upward  and  backward  in  the  line  of 
the  pelvic  outlet  below  and  the  pelvic  axis  above.  It  forms  an  angle 
of  25  to  35  degrees  with  the  long  axis  of  the  body,  of  65  to  75  degrees 
with  the  horizon,  and  of  more  than  90  degrees  with  the  cervix,  but  these 
measurements  vary  with  the  pelvic  inclination  of  the  individual  and  with 
the  condition  of  the  bladder  and  rectum.  Nearly  half  of  it  lies  below 
the  plane  of  the  pelvic  outlet. 

Its  walls  are  ordinarily  in  contact,  and  it  presents  on  transverse  section 
an  H-shaped  fissure.  In  the  knee-chest  position  the  walls  are  separated 
and  the  cavity  distended  by  air,  affording  easy  inspection.  Its  anterior 
wall  measures  6.5  to  7.5  cm.  (2^  to  3  in.)  in  length,  the  posterior  nearly 
8.5  cm.  (3^  in.).  In  the  lateral  dimensions  it  is  extraordinarily  dilatable, 
being  limited  only  by  the  pelvic  wall  so  as  to  admit  the  passage  of  the 
fetus  at  birth.  The  anterior  wall  is  in  close  relation  with  the  urethra 
below  and  the  bladder  above.  The  trigonum  vesica?  and  the  base  of  the 
bladder  just  above  it  are  connected  with  the  vaginal  wall  by  areolar 
tissue,  continuous  with  the  subperitoneal  tissue  between  the  cervix  and 
the  bladder.  So  close  is  this  connection,  especially  with  the  trigonum, 
that  when  the  vagina  is  everted  like  a  glove-finger  in  prolapse  of  the  uterus 
the  bladder  wall  is  drawn  down  with  it  as  a  pouch  projecting  into  the 
vagina  (cystocele).  In  complete  prolapse  the  urethra,  the  lower  two- 
thirds  of  which  is  most  intimately  connected  ivith  the  vaginal  wall,  is 
also  inverted,  so  that  from  the  meatus  its  direction  is  downward  and 
backward.  When  the  support  afforded  by  the  perineum  is  weakened  by 
its  rupture  a  cystocele  may  project  into  the  vagina  without  uterine  pro- 
lapse, but,  according  to  Sims,  a  cystocele  always  precedes  complete 
prolapse  of  the  uterus. 

Owing  to  prolonged  pressure  between  the  fetal  head  and  the  pubic 
bones  during  a  tedious  labor,  the  vesicovaginal  septum  may  slough  and 
give  rise  to  a  vesicovaginal  fistula.  Similar  fistulae  may  also  occur  from 
a  like  cause  between  the  urethra  and  vagina  or  between  the  bladder  and 
cervical  canal,  or  these  three  forms  of  fistulse  may  be  combined  in  one. 

The  trigonum  vesica'  is  faintly  indicated  on  the  anterior  vaginal  wall  as 
follows:  the  base  by  a  t ransverse  fold  of  mucous  membrane,  slightly 
convex  inferiorly,  about  2.5  to  3  cm.  below  the  external  os  uteri,  and 
the  sides  by  two  folds  which  diverge  from  the  upper  end  of  the  ante- 
rior columna  rugarum.  Pawlik  used  these  markings  in  catheterizing 
tin-  wreters,  whose;  openings  are  at  the  upper  angles  of  the  trigonum, 
but  we  have  ail  easier  and  surer  way  in  Kelly's  method  through  a 
urethral  speculum.  Above  the  base  of  the  trigonum  the  ureters  pass 
upward  and  outward,  diverging  somewhai  so  as  to  reach  the  upper  end 
of  tin-  lateral  vaginal  walls,  where  they  occupy  the  triangular  space 
en  the  levator  ani  muscle  and  the  vagina.     Calculi  lodged  in  the 

lower  6  to  7.5  cm.  ('2\  to  '■'>  in.)  of  the  ureters  may  therefore  be  felt  and 

removed  through  the  upper  pari  of  the  vagina, 


448  PELVIS  AND  PERINEUM 

The  lateral  walls  of  the  vagina  are  in  contact  above  with  the  base  of 
the  broad  ligaments  and  their  contents,  including  the  uterine  vessels. 
Hence  we  can  here  palpate  or  expose  these  parts  by  incision  (see  Broad 
Ligaments,  p.  444).  In  its  lower  two-thirds  the  lateral  vaginal  wall 
is  embraced  by,  but  not  attached  to,  the  median  portion  of  the  levator 
ani  muscles,  which  with  the  rectovesical  fascia  effectively  support  it. 
In  the  triangular  space  between  these  structures  and  the  sides  of  the 
vagina  is  the  vesicovaginal  plexus  of  veins. 

The  posterior  vaginal  wall  is  in  contact  with  the  rectum,  from  which 
its  upper  fourth  (2  cm.  or  so)  is  separated  by  the  peritoneal  pouch  of 
Douglas,  its  middle  portion  by  areolar  tissue,  continuous  with  the  sub- 
peritoneal connective  tissue,  and  its  lower  end  by  the  perineal  body. 
Hence  we  can  palpate  through  the  vagina  the  contents  of  the  lower  end 
of  Douglas'  pouch,  whether  this  be  the  coils  of  intestine,  normally 
present,  or  a  retro-uterine  hematocele,  a  retroflexed  uterus,  a  uterine 
fibroid,  a  displaced  and  perhaps  cystic  ovary,  or  a  pus  tube.  Through 
the  upper  end  of  the  posterior  vaginal  wall  we  may  reach  by  incision 
the  peritoneal  cavity  in  Douglas'  pouch,  and  through  this  incision  drain 
an  abscess,  break  up  adhesions  behind  the  uterus,  or  reach  and  operate 
upon  its  adnexa.  The  peritoneal  cavity  may  also  be  opened  by  trauma- 
tism inflicted  through  the  vagina,  and  through  such  an  opening  intestinal 
coils  may  protrude.  Rarely  the  intestinal  coils  occupying  Douglas' 
pouch  may  protrude  from  above  and  behind  into  the  vagina  as  an 
enterocele,  or  lower  down  the  rectum  may  form  a  similar  pouch,  or  recto- 
cele.  Such  a  pouch  does  not  necessarily  accompany  a  prolapse  of  the 
uterus  with  eversion  of  the  vagina,  for  the  latter  is  more  loosely  connected 
with  the  rectum  than  with  the  bladder,  and  may  not  pull  it  down.  Simi- 
larly in  prolapse  of  the  rectum  the  vagina  is  not  necessarily  pulled  down. 

Although  the  rectovaginal  septum  does  not  suffer  from  pressure  as 
does  the  vesicovaginal,  yet  it  may  be  torn  through  even  to  a  high  level 
at  childbirth.  If  such  a  complete  rupture  is  not  healed  throughout,  it 
may  leave  a  rectovaginal  fistula. 

The  upper  end  is  the  largest  part  of  the  vagina.  Its  angle  of  reflec- 
tion onto  the  cervix  is  known  as  the  fornix,  and  should  be  supple  when 
normal.  Into  this  upper  end  the  intra  vaginal  portion  of  the  cervix 
projects  at  an  angle.  (See  Uterus,  p.  435.)  The  line  of  vaginal  attach- 
ment is  oblique  from  behind  forward  and  downward,  making  the  pos- 
terior vaginal  fornix  much  deeper  than  the  anterior,  and  the  posterior 
vaginal  wall  longer  than  the  anterior,  so  that  it  may  occasionally  be  diffi- 
cult to  reach  the  limit  of  the  posterior  fornix  with  an  examining  finger 
of  moderate  length  (7.5  cm.)  without  considerable  pressure,  or  to 
explore  the  pouch  of  Douglas  without  general  anesthesia,  which  greatly 
facilitates  bimanual  examination. 

The  lower  end  is  the  narrowest  part,  and  may  be  still  further  nar- 
rowed by  the  engorgement  of  the  bulbs  of  the  vestibule,  which  flank  it  on 
either  side,  and  by  the  contraction  of  the  constrictor  or  sphincter  vagina 
and  perhaps  also  of  the  levatores  ani.  The  spasmodic  contraction  of 
the  constrictor  vaginae,  known  as  vaginismus,  may  interfere  with  coitus. 


THE  FEMALE  PELVIC  GENITAL  ORGANS 


449 


It  may  require  surgical  treatment,  but  the  surrounding  parts  should 
first  be  carefully  inspected  to  discover  if  possible  some  cause  of  reflex 
irritation.  As  the  vagina  near  its  lower  end  pierces  the  triangular 
ligament  and  is  intimately  attached  to  it,  this  part  of  the  canal  is  also 
the  most  resistant  to  dilatation.  The  lower  end,  orificium  or  introitus 
vagina,  is  partly  shut  off  from  the  vestibule  in  the  virgin  by  an  im- 
perfect septum,  the  hymen.  This  membranous  fold  varies  much  in 
shape,  but  it  is  usually  crescentic  and  attached  behind  and  laterally, 
having  an  opening  in  front,  although  it  may  form  a  complete  septum, 
with  one,  two,  or  several  small  openings,  or  occasionally  with  no  open- 
ing (imperforate  hymen).  The  latter  condition  causes  a  damming  back 
of  the  menstrual  flow,  which  fails  to  appear,  and,  unless  relieved,  distends 


Fig.  155 


DORSAL    V 
OF   CLITO 


Sagittal  section  of  the  vagina  and  neighboring  parts.      (Gerrish,  after  Testut.) 

the  vagina,  the  uterine  canal,  and  even  the  tubes,  and  hence  calls  for 
surgical  relief.  Although  the  hymen  is  usually  ruptured  by  the  first 
coitus,  it  may  not  be  until  parturition,  hence  it  is  not  a  proof  of  virginity, 
DOT  i  its  a  1 1-'  nee  incompatible  with  virginity.  After  parturition  remains 
of  tin-  hymen  appear  as  rounded  elevations  (carunculce  myrtiformes) 
around  the  orificium  vaginas,  the  exad  position  of  which  they  indicate. 

The  transverse  folds  of  the  vagina  render  sterilization  difficult  by 
favoring  the  retention  of  discharges.  Owing  to  the  continuity  of  the 
vaginal  and  uterine  mucosae,  infection  of  the  former  (vaginitis)  readily 
ipreads  to  the  latter  (endometritis I. 

\  to  structure,  the  very  elastic  mucosa,  lined  by  stratified  epithe- 
lium, is  destitute  of  glands,  hence  vaginal  discharge  is  of  the  nature 
of  b  Iran  udation.     Beneath,  the  mucosa  is  a  rich  venous  plexus,  which 

Si 


450  PELVIS  AND  PERINEUM 

may  be  regarded  as  erectile  tissue  and  may  become  varicose  and  form 
a  pile-like  tumor  near  the  external  orifice.  The  lymphatics  of  the 
lower  third  of  the  vagina  pass  to  the  supero-internal  group  of  inguinal 
nodes;  those  of  the  upper  two- thirds  pass  with  those  of  the  cervix  uteri. 
In  infancy  and  childhood  the  vagina  is  often  relatively  long,  correspond- 
ing to  the  high  position  of  the  pelvic  viscera;  in  old  age  it  undergoes 
atrophy  and  sometimes  partial  closure.  Congenitally  it  may  be  more 
or  less  completely  divided  by  a  vertical  septum  into  lateral  halves,  usually 
connected  with  the  halves  of  a  bifid  uterus.  Such  a  septum  may  require 
division  to  allow  parturition.  It  may  also  be  very  small  and  rudimentary, 
or  even  wanting.  In  the  latter  conditions  other  parts  of  the  genital 
system,  uterus  and  ovaries,  are  likely  to  be  rudimentary  or  wanting. 

The  Female  Urethra. — This  represents  that  portion  of  the  male 
urethra  between  the  internal  meatus  and  the  openings  of  the  ejaculatory 
ducts.  It  passes  through  the  two  layers  of  the  rather  indistinct  triangular 
ligament  and  the  striped  muscular  fibers  representing  the  compressor 
urethrse  muscle  (deep  transverse  perinei).  Striped  fibers  surround  the 
urethra  as  a  sphincter  in  its  upper  1  cm.  only,  where  it  is  connected 
to  the  vagina  by  loose  connective  tissue;  in  the  lower  part  of  the  urethra, 
where  the  urethral  and  vaginal  walls  blend  closely  to  form  the  urethro- 
vaginal septum  (1  cm.  thick  above),  these  fibers  occur  in  front  only. 
Circular  unstriped  fibers  together  with  fibers  from  the  trigone  surround 
the  vesical  end  and  form  a  powerful  sphincter.  As  may  be  proved  by  dis- 
tention of  the  bladder  in  the  cadaver,  no  muscular  action  of  the  sphincters 
is  necessary  to  retain  urine,  provided  there  is  no  vis  a  tergo  through  ab- 
dominal pressure  or  the  contraction  of  the  bladder. 

The  urethra  may  be  felt  between  the  anterior  vaginal  wall  and  the 
pubes  like  a  round  cord.  The  female  urethra  measures  3.5  cm.  (If  in.) 
in  length.  In  the  erect  position  it  is  directed  downward  and  slightly 
forward,  nearly  parallel  with  the  vagina,  though  inclining  more  for- 
ward below.  Hence  its  lower  end  is  farther  from  the  vagina  than 
the  upper  end.  It  is  slightly  convex  backward,  yet  not  enough  to  inter- 
fere in  any  way  with  the  passage  of  a  straight  catheter.  Its  exit  from 
the  bladder  is  a  little  below  and  2.5  cm.  (1  in.)  behind  the  middle  of  the 
symphysis.  It  passes  1.5  to  2  cm.  (f-  to  f  in.)  below  the  subpubic  arch, 
and  its  external  meatus,  usually  a  sagittal  fissure  about  5  mm.  in  length, 
is  found  near  the  base  of  the  vestibule  on  a  papilla  2.5  cm.  (1  in.)  behind 
the  clitoris,  and  1.5  to  2  cm.  below  the  subpubic  arch.  It  is  possible 
after  practice  to  pass  a  catheter  without  exposure  of  the  parts  by  means 
of  the  latter  measurements,  or  better  by  means  of  a  tubercle  just  behind 
the  meatus  at  the  lower  end  of  the  anterior  columna  rugarum  of  the 
vagina.  This  practice  is  to  be  condemned,  however,  as  it  is  much  more 
likely  to  carry  infection  to  the  bladder  than  when  done  aseptically  with  the 
aid  of  sight.  In  children  and  when  the  parts  are  swollen,  as  after  a 
difficult  labor,  the  meatus  is  relatively  far  back  and  difficult  to  find. 

The  meatus  is  the  narrowest  part  of  the  canal,  which  averages  7  to 
8  mm.  in  diameter,  but  it  is  extremely  dilatable,  as  it  is  not  surrounded 
by  dense,  resisting  structures  as  in  the  male.      Thus  it  may  be  gradu- 


THE  FEMALE  EXTERNAL  GENITALS  451 

ally  dilaied  under  a  local  or  general  anesthetic  so  as  to  allow  the  removal 
of  small  calculi  or  foreign  bodies,  and  the  introduction  of  the  finger 
for  exploration  or  of  the  cystoscope  for  examination  or  ureteral  catheter- 
ization. The  resulting  'paralysis,  if  it  occurs,  quickly  disappears  unless 
the  dilatation  has  been  too  great  and  too  abrupt,  when  it  may  persist,  as 
reports  of  cases  show.  In  cases  of  imperforate  hymen  and  narrowness 
or  absence  of  the  vagina  the  urethra  lias  even  become  the  channel  of 
sexual  intercourse. 

In  the  submucosa  is  a  cavernous  venous  plexus  which  gives  the  mucosa 
a  darkish  hue  during  life  and  may  become  varicose  and  form  a  pile-like 
tumor  near  the  meatus.  Small  vascular  tumors  (papillary  angiomata) 
may  spring  from  the  mucous  membrane  at  or  near  the  meatus,  espe- 
cially in  its  posterior  segment.  These  "urethral  caruncles"  bleed  readily, 
and  are  highly  sensitive  and  sometimes  very  painful,  so  as  to  give  rise 
to  marked  local  and  general  symptoms  and  to  demand  removal. 

Since  the  female  urethra  is  a  short,  wide  tube  which  serves  the  pur- 
pose of  a  urethra  only,  inflammation  is  less  common,  less  severe,  and 
easier  to  treat  than  in  the  male,  and  stricture  is  rare,  less  complete, 
and  often  requires  no  treatment. 


EXTERNAL  GENITALS. 
A.     THE  FEMALE  EXTERNAL  GENITALS. 

The  Vulva. — The  vulva  is  really  a  cleft-like  space  between  the  rima 
pudendi  (the  urogenital  cleft  between  the  two  labia  majora)  infer- 
iorlv,  and  the  hymen  or  its  remains  superiorly.  It  includes  all  the 
other  external  genitals  in  the  female.  The  two  labia  majora  represent 
tli»-  two  lateral  halves  of  the  scrotum  in  the  male,  and,  like  it,  are  composed 
of  skin  enclosing  an  imperfectly  developed  dartos,  and  are  subject  to  the 
same  pathological  conditions.  They  are  the  usual  situation  of  elephan- 
tiasis in  the  female,  are  greatly  swollen  in  cases  of  edema,  and  may  contain 
large  extravasations  of  blood  (pudendal  hematocele)  after  injury.  They 
contain  ;i  considerable  amount  of  fat,  with  whose  fibrous  capsule  and 
partitions  the  round  ligament  is  connected.  Inguinal  hernia?  (sometimes 
containing  the  ovary)  may  descend  into  them  anteriorly,  pudendal 
hernia,  which  escape  between  the  vagina  and  the  pubic  ramus,  more 
posteriorly.  ( lystic  collections,  probably  in  the  unclosed  canal  of  Nuck, 
and  known  as  "hydrocele  in  the  female,"  may  also  occur  in  the  labia 
majora. 

Po  teriorly  their  ends  taper  and  blend  with  the  perineum,  and  are 
usually  connected  by  a  transverse  fold,  the  posterior  commissure,  a  little 
in  front   of  the  arm 

The  Labia  Minora  or  Nymphae.  The  labia  minora  or  nymphse 
contain  much  vascular  tissue,  and  are  not  infrequently  redundant,  pro- 
jecting below  the  vulva,  especially  in  certain  races  (/.  e.,  Hottentots,  etc.). 
On  approaching  the  median  line  anteriorly  (hey  bifurcate  and   their 


452  PELVIS  AND  PERINEUM 

branches  unite  from  side  to  side  to  form  the  preputium  and  the  frenulum 
of  the  clitoris.  Extravagant  importance  has  been  attached  by  some  to  the 
adhesion  of  this  prepuce  to  the  clitoris  as  a  cause  of  various  symptoms. 
In  the  young  subject  the  posterior  ends  of  the  nymphse  are  usually  con- 
nected by  a  crescentic  fold,  the  frenulum  or  fourchette,  which  is  often  torn 
in  parturition  and  is  the  common  seat  of  chancres  in  the  female. 

The  bulbi  vestibuli,  two  pyriform  masses  of  erectile  tissue  correspond- 
ing to  the  lateral  halves  of  the  corpus  spongiosum  of  the  male,  lie  on  either 
side  of  the  orifice  of  the  vagina  and  extend  thence  on  either  side  of  the 
vestibule,  beneath  its  mucous  membrane,  to  a  point  below  the  clitoris, 
where  the  two  connect  with  one  another  and  with  the  glans  clitoridis. 
Rupture  of  the  bulb  may  occur  from  injury,  especially  during  pregnancy, 
when  they  are  enlarged,  and  results  in  the  formation  of  a  large  hema- 
toma (pudendal  hematocele). 

Often  overlapped  by  the  bulbi  vestibuli  and  on  either  side  of  the 
posterior  third  of  the  vaginal  orifice  lie  the  two  vulvovaginal  glands  (the 
glands  of  Bartholin),  which  probably  represent  Cowper's  glands  in  the 
male.  The  ducts,  18  mm.  (f  in.)  long,  open  just  outside  of  the  vaginal 
orifice  and  a  little  behind  its  centre,  where  the  opening  may  often  be  seen 
as  a  small,  red  depression  on  everting  the  nymphse  and  pressing  the 
hymen  inward.  The  glands  are  8  to  12  mm.  ( -j  to  ^  in.)  long,  lie  beneath 
the  superficial  perineal  fascia,  and,  like  the  bulbi  vestibuli,  are  covered 
externally  by  the  sphincter  vaginee  (bulbocavernosus)  muscle.  The  duct 
and  gland  are  liable  to  inflammation  and  suppuration,  often  of  gonorrheal 
origin.  The  resulting  vulvovaginal  abscess  is  felt  in  the  base  of  one  of 
the  labia  majora  and  cause  edema  there.  Cystic  dilatation  of  the  duct 
is  not  infrequent.  These  glands  atrophy  after  the  menopause,  if  not 
before.  In  general,  the  vessels  and  nerves  of  the  external  genitals  cor- 
respond to  those  of  the  homologous  parts  in  the  male;  thus  the  lym- 
phatics enter  the  inguinal  nodes. 


B.  THE  MALE  URETHRA  AND  EXTERNAL  GENITALS. 

The  Male  Urethra. — The  urethra  is  to  be  regarded  as  a  closed 
valve  whose  walls  are  usually  in  contact.  It  is  a  canal  only  when  open 
for  the  passage  of  urine,  semen,  or  instruments. 

Divisions. — In  its  passage  from  the  bladder  at  the  vesical  outlet,  or 
internal  meatus,  to  the  external  meatus  it  is  divided  in  various  ways 
according  to  (1)  the  parts  through  which  it  passes  (prostatic,  mem- 
branous, spongy,  etc.),  (2)  its  fixity  and  mobility,  (3)  its  direction 
(curved  or  straight),  (4)  its  pathological  and  therapeutic  peculiarities 
(anterior  and  posterior  urethra). 

The  Prostatic  Urethra.— The  prostatic  urethra,  2.5  to  3  cm.  (1  to  li  in.) 
long,  is  spindle-shaped.  Its  upper  narrowed  end,  the  vesical  outlet  or 
internal  meatus,  is  formed  by  the  annulus  urethralis  (see  p.  459).  The 
latter  is,  as  a  rule,  quite  dilatable,  but  may  become  thickened  or  more 
resistant  as  the  result  of  spasmodic  action  during  micturition  in  gouty 


THE  MALE   URETHRA  AND  EXTERNAL  GENITALS 


453 


subjects  or  in  those  with  chronic  urethral  trouble.  In  such  cases  the 
condition  may  be  relieved  by  stretching,  with  or  without  a  slight  incision. 
If  in  such  cases  the  prostatic  sinus  is  deep,  the  beak  of  the  catheter  or 
sound  may  impinge  on  its  posterior  wall,  under  the  back  of  the  annulus, 
and  thus  enter  the  bladder  with  difficulty  if  at  all. 


Fig.  156 


MEM  BRANOUS 
PORTION 


MEATUS 

Hie  male  urethra  laid  open  on  iti  anterior  (upper)  surface.     (Gerrisli,  after  Testut.) 

The  central,  dilated  pari  «»i'  the  prostatic  urethra  presents  an  in/verted 
V  on  cross-section,  owing  t<>  the  median  projection  from  behind  of  the 
verumontanum.  This  contains  erectile  tissue,  and  may  serve  to  dose  the 
upper  end  of  the  urethra  and  prevent  the  passage  <>!'  semen  back  into  the 
bladder.  On  ii-  summit  in  tin-  median  line  is  the  fair-sized  opening  of 
ill'  urn .  pocularis,  or  uterus  masculinue,  the  homologue  of  the  uterus. 
I  hi  Mind  sinus  runs  upward  and  backward  for  6  to  12  mm.  (i  to  £  in.) 
beneath  the  "middle  lobe."    On  either-side  of  it  run  the  ejacidatory 


454  PELVIS  AND  PERINEUM 

ducts,  whose  slit-like  openings  are  on  either  side  of  (sometimes  within) 
that  of  the  sinus.  In  the  two  depressions  or  prostatic  sinuses,  one  on 
either  side  of  the  verumontanum,  open  the  ducts  of  the  glands  of  the 
prostate,  of  which  two  are  larger  and  more  noticeable  than  the  others. 
The  tip  of  a  sound  may  lodge  in  the  prostatic  sinuses,  especially  in 
cases  of  prostatic  enlargement.  To  avoid  this  the  beak  of  a  "prostatic 
catheter"  is  longer  and  curved  farther  forward  and  the  flexible  catheters 
are  made  with  the  tip  bent  up  (Mercier's  coude  catheter).  The  tip  of 
a  small  sound  or  bougie  may  also  lodge  in  the  sinus  pocularis  unless  it 
is  made  to  hug  the  upper  wall.  On  account  of  the  various  openings 
into  the  prostatic  urethra  we  can  understand  how  an  inflammation  of 
this  part  may  extend  (1)  Into  the  bladder  and  thence  to  the  ureters  and 
kidneys,  (2)  into  the  ejaculatory  ducts  and  thence  to  the  seminal  vesicles 
or  along  the  vas  deferens  to  the  epididymis,  etc.,  or  (3)  into  the  substance 
of  the  prostate. 

In  the  erect  position  the  course  of  the  prostatic  urethra  is  nearly 
vertical,  with  a  slight  concavity  forward.  It  runs  in  front  of  the  middle 
of  the  upper  two-thirds  and  about  the  middle  of  the  lower  one-third  of 
the  gland,  although  cases  have  been  observed  when  it  has  merely  occupied 
a  groove  on  its  anterior  surface.  The  prostatic  portion  is  not  only  of 
large  caliber,  but  also  very  dilatable,  readily  admitting  the  passage  of  the 
finger  in  operations  on  the  urethra  or  bladder.  Stricture  is  unknown 
in  this  part,  although  congenital  folds  and  pockets  may  occur  here  and 
interfere  with  micturition.  The  lower  half  of  the  prostatic  urethra 
may  be  incised  in  the  median  line  without  injuring  other  structures. 
Median  incisions  in  the  upper  half  must  be  in  the  exact  median  line  to 
avoid  the  ejaculatory  ducts. 

The  membranous  portion,  or  that  lying  between  the  two  layers  of 
the  triangular  ligament,  is  directed  obliquely  downward  and  forward, 
and  forms  the  beginning  of  the  subpubic  curve.  It  is,  next  to  the 
external  meatus,  the  narrowest  segment  and  measures  about  12  mm. 
(i  in.)  in  length,  although  the  floor  is  said  by  some  to  measure  less  than 
the  roof,  owing  to  the  projection  backward  of  the  bulb  along  the  floor. 
It  is  surrounded  by  the  compressor  urethrce  muscle,  which  forms  the  dividing 
line  between  the  anterior  and  posterior  portions  of  the  urethra,  and  the 
cause  of  the  so-called  spasmodic  strictures.  Close  behind  it  lies  the 
bend  in  the  anterior  wall  of  the  rectum  between  the  anal  and  pelvic 
portions.  At  this  point  an  instrument  can  be  felt  within  or  guided  into 
the  membranous  urethra,  or  the  false  passage  of  an  instrument  may  be 
felt  by  the  finger  in  the  rectum.  Beneath  and  on  either  side  lie  the  bulbo- 
urethral glands  (Cowper's  glands),  the  homologue  of  the  glands  of  Bar- 
tholin in  the  female.  Enclosed  by  the  compressor  urethra?  muscle  and 
resting  on  the  upper  surface  of  the  superficial  layer  of  the  triangular 
ligament,  5  mm.  (A  in.)  apart,  these  glands  thus  lie  above  and  behind  the 
bulb.  The  formation  of  cysts  or  abscess  may  occur  in  them,  the  latter 
by  extension  of  gonorrheal  inflammation  from  the  bulbous  urethra, 
into  the  floor  of  which  their  ducts,  1.5  to  2.5  cm.  (f  to  1  in.)  long,  open. 
They  .atrophy  as  age  advances. . 


PLATE  XLV 


FIG.  157 


MUSCULAR   WALL 
OF    BLAD 


DINAL  MUS 
CLES  OF  URETHRA 


Proximal  Portions  of  Urethra,  with  surrounding  parts. 
(Gerrish,  after  Testut. ) 


FIG.   158 


—  1 


LOWEST   POINT  OF 
URETHRAL  CURVE 


Outline    Diagram    of   the    Curved    Portion    of    the    Urethra, 
ving  the  distances   from   and  the   relations  of  the  different 
parts  to  the  symphysis.     (Testut.  ( 


THE  MALE   URETHRA  AND  EXTERNAL  GENITALS  455 

The  spongy  portion,  13.5  cm.  (5^  in.)  in  length,  includes  several  subdivi- 
sions. The  bulbous  portion,  about  2.5  cm.  in  length,  is  the  most  posterior. 
Immediately  in  front  of  the  triangular  ligament  the  bulb  at  first  covers 
only  the  floor  and  then  gradually  the  sides,  while  the  front  of  the  urethra 
is  not  covered  by  spongy  tissue  until  0.5  to  1  cm.  lower  down,  so  that  some 
authors  call  the  portion  not  covered  by  the  bulb  the  pre-diaphragmatic 
or  pre-trigonal  portion.  The  front  wall  of  the  latter  portion  is  thinner 
than  elsewhere.  Along  the  floor  of  the  bulbous  portion  the  urethra  is 
much  dilated,  and  this  dilatation  (fossa  bulbi)  passes  suddenly,  not  by 
a  gradual  narrowing,  into  the  narrow  and  firmly  fixed  membranous 
portion  at  the  point  where  the  latter  pierces  the  firm  anterior  layer  of 
the  triangular  ligament.  This  is  the  critical  point  in  the  passage  of 
instruments,  for  if  the  instrument  is  allowed  to  follow  the  floor  it  sinks 
into  the  dilatation  of  the  bulb  below  the  level  of  the  opening  into  the 
membranous  portion  and  then  impinges  on  the  triangular  ligament,  or  if 
pressed  too  closely  against  the  thin,  dilatable  anterior  wall,  a  like  result 
may  happen.  To  enter  the  narrow  opening  of  the  membranous  urethra 
("neck  of  the  bulb,"  as  the  French  call  it)  the  sound  should  be  kept 
along  the  roof  of  the  urethra,  and  as  large  an  instrument  as  will  pass 
should  be  used,  for  it  is  less  likely  to  catch.  We  have  seen  that  hugging 
the  roof  is  also  the  rule  in  passing  the  prostatic  portion  to  avoid  catching 
in  the  sinuses  and  the  annulus. 

The  bulbous  portion  continues  the  subpubic  curve,  commenced  in  the 
membranous  portion,  and  in  the  erect  position  it  forms  the  most  dependent 
part  of  the  fixed  portion  of  the  urethra.  Hence  the  products  of  inflam- 
mation naturally  gravitate  here,  and,  as  the  parts  are  bathed  in  pus, 
chronic  inflammation  is  apt  to  linger  here  and  its  results  are  seen  in  the 
common  occurrence  of  stricture.  The  chronic  inflammation,  or  gleet, 
alters  the  lining  mucosa  so  that  plastic  material  is  deposited  beneath  it 
to  prevent  the  soaking  of  urine  into  the  surrounding  tissues.  The  natural 
contraction  of  this  plastic  exudate  narrows  the  lumen,  and  stricture 
results.  This  keeps  up  the  irritation  and  the  discharge,  which  is  only 
cured  by  the  cure  of  the  stricture.  The  bulb  is  covered  externally  by 
the  accelerator  urinae  muscle  (bulbocavernosus) . 

In  front  of  the  bulb  the  urethra  continues  in  a  fixed  position,  nearly 
horizontally,  but  with  a  slight  upward  inclination,  to  a  point  beneath  the 
suspensory  ligament.  In  front  of  this  ligament  the  urethra  is  movable 
with  the  penis.  The  caliber  of  the  spongy  urethra  is  fairly  uniform 
between  the  bulb  and  the  fossa  navicularis,  the  dilatation  in  the  glans 
penis,  especially  along  the  urethral  roof.  At  its  distal  end  this  fossa 
ends  in  the  external  meatus,  a  vertical  slit  on  the  antero-inferior  aspect 
of  the  glaus.  Tne  meatus  is  the  narrowest  and  least  dilatable  portion 
of  the  urethra,  to  that  any  Instrument  which  can  pass  the  meatus  should 

■  l  a   normal  urethra.      To  allow  the  use  of  large  sounds  or 

instruments  in  the  treatment  of  pathological  conditions  of  the  rest  of 
the  urethra  or  the  bladder  (i.  e.,  litnolapaxy,  cystoscopy,  etc.)  the  meatus 
nusl  be  enlarged  by  slitting  it  Lnferiorly  in  the  middle  of  <h<-  frenum. 

The  mcatii     ma .    be  oongenitally  small,  even  admitting  only  a  line 


456  PELVIS  AND  PERINEUM 

probe.  This  condition  is  often  associated  with  congenital  phimosis, 
and  may  occasion  sufficient  reflex  nervous  disturbances  and  urinary 
obstruction  to  require  meatotomy.  Besides  the  many  mucous  glands 
found  in  all  parts  of  the  urethra,  especially  in  and  near  the  navicular 
fossa,  the  small  pits  or  lacunas  of  Morgagni  occur  in  the  spongy  portion 
in  longitudinal  rows,  a  median  row  of  larger  lacunae  on  the  anterior  or 
upper  wall  and  a  row  of  smaller  lacunae  on  either  side  of  it.  As  the 
openings  of  these  lacunae  are  directed  toward  the  meatus,  the  larger  ones 
may  catch  the  tip  of  a  small  sound  or  bougie,  thereby  interfering  with 
treatment  or  misleading  the  diagnosis.  Hence  instruments  should  be 
passed  along  the  lower  wall  or  floor  of  the  spongy  portion.  An  additional 
reason  for  this  is  found  in  the  presence  of  a  lacuna  of  large  size,  the 
lacuna  magna,  1  to  2.5  cm.  (^  to  1  in.)  from  the  meatus,  in  the  roof  of 
the  navicular  fossa,  which  may  easily  arrest  the  point  of  an  instrument. 
It  is  nearly  covered  below  by  a  semilunar  valve-like  fold  (the  valvule 
of  Guerin). 

According  to  its  fixity  the  urethra  is  divided  into  a  fixed  and  a  mov- 
able part  (pars  fixa  and  pars  mobilis).  These  divisions  do  not  corre- 
spond to  the  preceding,  but  more  to  the  next  following  division,  for  the 
fixed  portion  includes  the  prostatic,  the  membranous,  and  the  proximal 
5  cm.  (2  in.)  of  the  spongy  portion,  or  as  far  as  the  anterior  border  of  the 
suspensory  ligament.  This  is  also  known  as  the  perineal  urethra,  the 
remainder  as  the  penile  urethra.  The  membranous  portion  is  the  only 
absolutely  fixed  part,  and  therefore  of  the  greatest  importance  in  catheter- 
ization, for  we  must  direct  the  catheter  to  and  through  it;  its  position 
does  not  change  to  suit  the  catheter.  The  prostatic  portion  may  be 
moved  within  the  moderate  limits  allowed  by  the  puboprostatic  liga- 
ments and  the  other  connections  of  the  prostate.  The  bulbous  portion 
is  the  most  movable  part  of  the  fixed  portion,  and  lies  immediately  in  front 
of  the  most  fixed  part.  This  is  one  reason  for  the  difficulty  of  directing 
the  point  of  the  catheter  or  sound  into  the  membranous  portion,  for 
the  bulb  may  be  easily  pushed  backward  or  sideways.  The  rest  of  the 
spongy  portion  of  the  urethra  is  the  pars  mobilis,  and  it  depends  for  its 
position  and  direction  upon  that  of  the  penis.  For  the  introduction  of 
instruments  this  portion  may  be  put  in  the  most  suitable  position  for  the 
purpose. 

In  direction  the  urethra  is  median,  but  may  deviate  somewhat  later- 
ally in  micturition.  It  presents  a  curve,  concave  forward  and  upward, 
beneath  the  symphysis,  the  subpubic  curve,  and  a  pre  pubic  curve  where 
the  fixed  and  movable  portions  join.  The  latter  curve,  with  its  con- 
cavity downward,  is  at  the  junction  of  the  fixed  and  movable  portions, 
and  is  present  in  the  flaccid  state  of  the  penis,  but  is  obliterated  when 
the  penis  is  erected  or  raised  up.  Hence  in  the  passage  of  instruments 
we  raise  the  penis  and  have  to  deal  only  with  the  subpubic  curve.  The 
latter  curve  is  most  marked  in  the  membranous  and  bulbous  portions, 
although  it  is  continued  slightly  in  the  upward  direction  in  the  prostatic 
urethra,  which  is  nearly  vertical,  and  in  the  forward  direction  about  to  the 
prepubic  curve,  or  the  end  of  the  fixed  portion,  though  the  anterior  portion 


THE  MALE   URETHRA  AND  EXTERNAL  GENITALS  457 

of  this  rises  but  little,  5  to  6  mm.  (-i-  to  \  in.),  above  the  level  of  the  lowest 
point  of  the  curve.  The  curve  (Fig.  152)  is  described  as  being  an  arc 
of  a  circle  having  a  diameter  ranging,  according  to  different  authors, 
from  8  to  12  cm.  (3\  to  4A  in.),  the  chord  of  the  arc  measuring  about 
5.5  to  7  cm.  (2i  to  2f  in.).  The  curve  is  sharper  in  small,  thin  men, 
and  flatter  in  large,  stout  men.  For  the  relations  of  the  curve  to  the 
symphysis  and  its  axis  see  Fig.  157.  The  subpubic  curve  belongs  to 
the  fixed  portion  of  the  urethra,  and  hence  metal  urethral  instruments 
are  made  with  a  definite  curve  to  allow  them  to  take  the  curve  of  the 
urethra  without  letting  the  tip  impinge  or  catch  on  the  floor.  It  is 
possible  to  pass  a  stiff,  straight  instrument  or  a  straight  one  with  a 
slight  terminal  bend  into  the  bladder,  but  not  without  painful  tension  of 
the  connections  of  the  urethra,  especially  the  suspensory  ligament,  and 
hence  it  is  often  done  under  anesthesia  and  only  for  certain  objects,  as 
cystoscopy,  litholapaxy,  etc.  The  pain  may  be  diminished  by  pressing 
downward  on  both  sides  of  the  root  of  the  penis  and  thus  flattening 
the  anterior  end  of  the  curve  by  slightly  elongating  the  suspensory  liga- 
ment. 

The  division  into  anterior  and  posterior  urethra?  occurs  between  the 
membranous  and  the  bulbous  portions,  at  the  level  of  the  superficial  layer 
of  the  triangular  ligament.  This  division  is  of  practical  importance 
from  a  pathological,  prognostic,  and  therapeutic  standpoint.  The  dis- 
charge from  a  urethritis  of  the  anterior  urethra  drips  from  the  meatus, 
and  injections  into  this  part  escape  at  the  same  point.  A  urethritis  also 
is  often  limited  to  this  part,  for  the  compressor  urethra?  muscle  offers 
an  obstacle  to  its  further  extension.  Among  the  chief  symptoms  are: 
(1)  Ardor  urinse,  due  chiefly  to  the  contact  of  the  acid  urine  with  the 
inflamed  mucosa;  (2)  frequent  painful  erection.  The  common  causes 
of  erection  (p.  463)  are  excited  by  the  inflammation,  and  the  pain  is  due 
to  the  loss  of  elasticity  of  the  mucosa.  The  complications  of  such  an 
anterior  urethritis  are  principally  chordee,  gleet,  and  stricture.  When 
an  inflammation  extends  into  the  posterior  urethra  or  an  injecting  catheter 
is  introduced  beyond  the  compressor  urethra?  muscle,  the  discharge  or 
injection  above  this  muscle  flows  into  the  bladder  and  does  not  appear 
at  the  meatus.  Frequent  urination  and  tenesmus  are  prominent  symp- 
toms. The  normal  desire  to  urinate  when  urine  enters  the  prostatic 
urethra  is  made  uncontrollable  on  account  of  the  sensitiveness  of  the 
inflamed  prostatic  mucosa.  The  inflammation  here  is  also  liable  to 
spread  to  the  bladder, vaa  deferens,  epididymis  seminal  vesicles,  prostate, 
and  kidneys  by  continuous  extension  or  otherwise,  hence  the  prognosis 
of  posterior  urethritis  is  more  grave.  By  using  considerable  pressure 
and  preventing  the  escape  at  the  meatus,  fluid  may  be  injected  into  the 
bladder  Prom  any  point  in  the  anterior  urethra. 

Embryologically  also  the  posterior  urethra  is  of  a  different  formation 
'.,  from  the  Urogenital  sinus),  and  corresponds  to  the  urethra  and 
tibllle  in  the  female,  while  the  anterior  urethra  is  formed  by  the 
genital   Folds  of  the  external  genitals. 

The  length  of  the  urethra  from  the   internal  to  the  external   meatus 


458  PELVIS  AND  PERINEUM 

varies,  but  averages  about  17.5  cm.  (7  in.)  in  the  adult.  It  varies  with 
the  length  of  the  penis;  when  the  latter  is  contracted  to  the  utmost  it 
may  be  considerably  (over  2.5  cm.)  shorter;  when  the  penis  is  more  or 
less  erected,  or  is  pulled  upon  during  catheterization,  the  urethra  may 
measure  20  cm.  (8  in.)  or  more.  Hypertrophy  of  the  prostate  also 
lengthens  the  urethra,  a  fact  which  is  useful  in  the  diagnosis  of  this  con- 
dition. The  length  of  the  urethra  at  birth  is  5  to  6  cm.;  in  children  of 
five  years,  8  to  10  cm.;  at  the  beginning  of  puberty,  10  to  12  cm. 

The  normal  caliber  or  diameter  of  the  urethra,  being  that  of  a  cylinder 
which  separates  the  walls  without  stretching  them,  can  only  be  given 
approximately  except  for  the  external  meatus.  Sappey  states  that, 
exclusive  of  the  meatus,  the  urethral  circumference  ranges  between 
15  and  18  mm.,  so  that  a  No.  15  (French)  sound  could  be  passed 
without  stretching  the  canal.  The  meatus  is  about  6  mm.  (J  in.) 
in  its  long  diameter.  Of  more  practical  importance  are  the  absolute 
and  relative  distensibility.  The  former  is  represented  by  a  cylinder 
averaging  10.5  mm.  in  its  diameter  (Joessel,  Waldeyer).  The  dis- 
tensibility varies  in  different  parts,  and  as  we  pass  from  end  to 
end  of  the  urethra  we  find  that  a  narrow  portion  alternates  with  a 
wider  portion.  Thus  the  narrow  portions  are,  in  order,  the  external 
meatus,  spongy  portion,  membranous  portion,  and  internal  meatus; 
the  wider  portions  are  the  fossa  navicularis,  the  bulbous  portion, 
and  the  prostatic  portion.  In  order  of  distensibility  we  find  the 
meatus  the  least  distensible,  next  the  membranous  portion,  the  spongy 
portion,  the  bulbous  portion,  and  lastly  the  prostatic  portion,  which  is 
the  most  distensible.  The  different  parts  should  distend  so  as  to  admit 
the  following  sounds  of  the  French  scale:  the  meatus,  No.  24;  the  spongy 
portion,  Nos.  28  to  30;  the  bulbous  portion,  No.  32;  the  membranous 
portion,  Nos.  26  to  27;  and  the  prostatic  portion,  Nos.  32  to  34. 

Otis  proved  that  the  distensibility  of  the  urethra  was  greater  than 
formerly  supposed,  though  Guyon  snowed  that  by  the  passage  of  large 
sounds,  31  to  34  (French),  on  the  cadaver  lacerations  were  produced, 
especially  on  the  floor  of  the  penile  portion.  According  to  Otis,  there 
exists  a  constant  ratio  of  nine  to  four  between  the  circumference  of  the 
penis  and  that  of  the  distended  urethra.  Apart  from  the  fact  that  it  is 
improbable  that  such  an  exact  mathematical  ratio  is  constant,  it  is 
difficult  in  measuring  an  organ,  so  variable  in  size  as  the  penis,  to  measure 
the  latter  in  the  same  condition  of  relative  size  in  different  cases.  Though 
the  caliber  is  not  as  large  as  the  above  ratio  would  indicate,  still  Otis' 
law  is  of  value  as  a  practical  guide  to  the  surgeon. 

The  relative  position  of  some  parts  of  the  urethra  may  be  more  fully 
given.  The  internal  meatus  is  on  a  level  with  the  middle  of  the  sym- 
physis, or  somewhat  below  or  above  it.  It  lies  above  this  point  in 
young  subjects,  and  not  infrequently  in  adults.  The  prostatic  portion, 
in  whole  or  in  great  part,  lies  above  the  horizontal  plane  passing  through 
the  bottom  of  the  symphysis,  so  that  this  portion  is  often  entirely  behind 
the  symphysis.  The  deepest  point  of  the  subpubic  curve  is  in  the  bulb, 
and  lies  18  to  20  mm.  from  the  subpubic  angle,  usually  more  or  less 


THE  MALE  URETHRA  AND  EXTERNAL  GENITALS  459 

behind  the  vertical  plane  of  this  angle,  but  sometimes  beneath  or  even 
in  front  of  it.  We  have  already  referred  to  the  effect  on  the  frequency 
of  stricture  here  of  its  being  the  most  dependent  point  of  the  curve  in 
the  erect  posture.  The  prepubic  curve  lies  below  the  horizontal  plane 
of  the  subpubic  angle,  and  usually  5  to  6  mm.  (^  to  \  in.)  above  the 
lowest  level  of  the  urethra  in  the  bulb,  so  that  from  the  latter  the  urethra 
extends  slightly  upward  as  well  as  forward,  though  it  may  be  horizontal. 
Between  the  subpubic  curve  of  the  urethra  and  the  symphysis  lie  the  dorsal 
vein  of  the  penis  and  the  pudendal  plexus. 

On  cross-section  the  empty  urethra  is  represented  by  a  fissure  which 
is  vertical  at  the  external  meatus,  transverse  in  the  spongy  portion, 
stellate  in  the  membranous  portion,  and  like  an  inverted  U  in  the  pros- 
tatic portion.  A  form  of  rifling  is  involved  by  this  progressive  change 
in  shape,  which  may  account  for  the  spiral  form  of  the  normal  stream 
of  urine.  In  addition  the  mucous  membrane  of  the  collapsed  urethra 
is  in  longitudinal  folds. 



Sphincters  of  the  Urethra. — The  fixed  portion  of  the  urethra  passes 
through  a  continuous  layer  of  encircling  muscle  fibers,  both  plain 
and  striated.  This  is  formed  of  several  parts,  of  which  the  most  distal 
is  the  bulbocavernous  muscle.  The  internal  sphincter  is  composed 
of  plain  muscle  fibers,  derived  from  the  deep  layers  of  the  trigonum, 
which  pass  downward  and  forward,  obliquely  encircling  the  upper 
part  of  the  prostatic  urethra.  This  does  not  include,  but  is  below,  the 
circular  fibers  of  the  bladder,  which  are  aggregated  around  the  internal 
meatus  and  form  a  ring,  the  "annulus  urethralis."  The  external  or 
voluntary  sphincter  is  composed  of  striated  fibers  surrounding  the  urethra 
at  the  apex  of  the  prostate  and  continuous  below  with  the  compressor 
urethra-.  AVhen  the  bladder  becomes  distended  the  internal  sphincter 
yields  so  that  urine  enters  the  upper  part  of  the  prostatic  urethra,  where  it 
excites  the  desire  to  urinate,  which  is  resisted  by  the  voluntary  action  of 
the  external  sphincter  and  the  compressor  urethral. 

The  urethral  walls  also  contain  unstriped  longitudinal  fibers,  con- 
tinuous with  those  of  the  bladder,  and  some  circular  fibers,  as  far  as 
the  lower  end  of  the  bulbous  portion.  There  is  but  little  muscular 
tissue  in  the  walls  of  the  movable  portion  (pars  mobilis).  The  muscular 
of  the  urethra  appears  to  have  a  peristaltic  action,  whereby  a 
catheter  left  in  the  urethra  or  the  last  drops  of  urine  are  gradually 
expelled.     I  of  reverse  peristalsis  are  also  known  where  a  flexible 

instrument  insecurely  tied  has  been  pressed  into  the  bladder.  As  already 
noted,  the  compressor  urethra  is  the  dividing  line  between  the  anterior 
and  the  posterior  urethra,  and  is  also  the  cause  of  spasmodic  stricture. 
The  hitter  i  .  usually  due  to  B  reflex  from  some  point  of  irritation  in  the 
urethra  (stricture,  granular  patch,  etc.),  and  is  often  caused  by  the 
rough  use  of  instruments;  occasionally  it  may  be  due  to  an  abnormally 
small  meatus.  It  may  also  !><•  due  to  irritation  of  the  prostatic  urethra, 
as  from  inflammation  of  from  distention  of  the  bladder.  It  commonly 
yields  n>  steady,  easy  pressure.  The  retention  of  urine  following  oper- 
ations on  the  rectum,  anus,  He.,  is  thought  by  many  to  be  the  result 
of  vesical  inhibition  rather  than  of  urethral  spasm. 


460  PELVIS  AND  PERINEUM 

The  lymphatics  of  the  spongy  portion  communicate  with  those  of  the 
glans  and  enter  the  supero-internal  group  of  inguinal  nodes;  those  of  the 
rest  of  the  urethra  enter  the  internal  iliac  nodes.  A  bubo  may  result 
from  the  infection  of  the  anterior  urethra,  or  from  retention  of  discharge 
between  the  glans  and  prepuce,  causing  balanitis. 

Changes  According  to  Age. — In  children  the  urethra  is  shorter  (see 
p.  458)  and  narrower,  but  Keegan  has  shown  that  the  urethra  of  a  male 
infant  one  year  old  will  admit  instruments  for  litholapaxy,  and  that 
at  two  to  three  years  of  age  a  No.  9  and  at  eight  to  ten  years  a  No.  11 
lithotrite  may  be  passed.  Hence  lithotrity  and  litholapaxy  may  be 
performed  upon  quite  young  infants.  The  subpubic  curve  in  infants 
is  also  sharper,  owing  to  the  high  position  of  the  bladder.  In  old  age 
there  occurs  a  dilatation  of  the  fossa  of  the  bulb  and,  in  cases  of  enlarged 
prostate,  a  lengthening  and  narrowing  of  the  prostatic  portion,  often 
with  an  increased  forward  curve  of  the  vesical  end,  which  tends  to 
make  the  tip  of  instruments  catch  on  the  floor,  in  the  prostatic  sinus. 
I  ^Catheterization. — Catheterization,  or  the  introduction  of  instruments, 
is  of  such  importance  that  we  may  repeat  what  has  been  said  in  different 
places  above.  To  catheterize  properly  we  must  know  the  differences 
in^  direction,  mobility,  dilatability,  and  contractility  of  the  several 
portions  of  the  urethra,  for  direction,  not  force,  is  requisite,  and  the 
sound  must  follow  a  passage,  not  force  one.  Use  the  largest  instrument 
that  will  readily  pass,  as  it  is  safer  and  easier  and  sometimes  passes  where 
smaller  sizes  will  not.  In  the  spongy  urethra  pass  the  instrument, 
especially  if  it  be  small,  along  the  floor  to  avoid  catching  the  tip  in 
the  lacuna  magna,  or  in  the  dorsal  row  of  large  lacunae  behind  it.  The 
movable  urethra  (pars  mobilis)  accommodates  itself  to  the  shape  and 
direction  of  the  instrument,  which  is  commonly  held  over  and  parallel 
to  Poupart's  ligament,  the  penis  being  held  upward  and  to  either  side 
to  obliterate  the  prepubic  curve.  When  the  bulb  is  reached  the  handle 
of  the  instrument,  now  held  in  the  median  line,  is  brought  forward  and 
pressed  downward  to  elevate  the  tip  to  the  roof  so  as  to  find  the  opening 
into  the  membranous  portion.  The  finger  in  the  rectum  or  perineum 
may  also  help  to  raise  the  tip  of  the  instrument.  If  spasm  exists  use 
only  slight  steady  pressure,  principally  the  weight  of  the  instrument; 
never  press  hard.  Most  false  passages  start  from  the  depressed  floor  of 
the  fossa  bulbi,  posteriorly.  The  tip  of  the  instrument  should  continue 
to  follow  the  roof  of  the  membranous  and  prostatic  urethrce  so  as  to  follow 
the  curve  of  the  urethra  and  to  avoid  the  utricle  and  prostatic  sinuses ; 
this  is  done  by  a  gentle  depression  of  the  handle.  Remember  that  the 
urethral  curve  remains  regular  only  along  the  superior  wall;  the  dilata- 
tions are  along  the  floor. 

The  urethra  may  be  ruptured  by  being  crushed  between  the  pubic 
arch  and  a  hard  substance,  astride  of  which  the  patient  falls;  also  by 
sharp  fragments  in  fractures  of  the  pelvis.  The  parts  of  the  urethra 
most  often  injured  are  the  membranous  portion  in  pelvic  fractures  and 
the  bulbous  portion  in  falls  or  blows  on  the  perineum.  A  considerable 
length  of  the  spongy  urethra  may  be  crushed.     In  the  membranous 


THE  MALI-:   URETHRA    AND   EXTERNAL  GENITALS  461 

urethra  the  rupture  is  commonly  complete,  on  account  of  its  fixity  and 
it^  thin  walls. 

The  commonest  pathological  conditions  that  affect  the  urethra  are 
urethritis,  usually  gonorrheal,  and  its  sequela',  gleet  and  organic  stric- 
ture. The  latter,  as  stated  above,  is  most  common  in  the  bulbous  and 
membranous  portions,  as  is  also  traumatic  stricture  following  rupture 
of  the  urethra.  The  obstinacy  of  a  urethritis  in  yielding  to  treatment 
is  in  part  due  to  the  length  and  narrowness  of  the  canal,  to  the  dilated 
portions  which  serve  as  reservoirs  for  secretion,  but  especially  to  the 
numerous  folds,  lacuna?,  and  glands,  in  which  the  infection  may  remain 
chronic  or  dormant. 

The  Penis. — The  skin  covering  the  body  of  the  organ  is  continuous 
with  that  of  the  scrotum  and  is  destitute  of  fat,  highly  elastic,  thin,  and 
very  movable,  thus  allowing  its  changes  in  size.  Owing  to  its  movability, 
due  to  the  looseness  of  the  subcutaneous  tissue,  the  skin  should  not  be 
drawn  too  strongly  downward  over  the  glans  in  circumcision  or  ampu- 
tation of  the  penis,  otherwise  the  operator  may  be  startled  by  seeing  the 
skin  above  the  section  retract  to  the  base  of  the  organ.  In  very  large 
scrotal  hernia'  or  hydroceles  the  skin  and  loose  subcutaneous  tissue  of 
the  penis  may  be  drawn  upon  to  such  an  extent  to  cover  the  scrotal  mass 
that  the  penis  disappears  and  is  represented  by  a  mere  depression  in 

this  mass  from  which  the  urine  escapes. 

From  the  cervix  or  coronary  sulcus  the  skin  extends  down  over  but 
Outside  of  the  glans  a  variable  distance  and  is  then  doubled  upon  itself 
to  form  the  prepuce  or  foreskin.  The  inner  layer  of  the  prepuce  is 
attached  more  or  less  firmly  around  the  cervix,  to  be  thence  continued 
over  the  glans,  at  the  end  of  which,  dipping  into  the  meatus  for  6  mm. 
\  in.  ,  it  is  continuous  with  the  urethral  mucosa.  The  prepuce  at  birt h 
i>  relatively  very  long,  more  than  covering  the  glans. 

Winn  the  prepuce  is  so  tight  as  to  prevent  its  easy  retraction  the 
condition  i-  called  phimosis.  'The  preputial  orifice  may  only  admit  a 
small    probe,    or,   rarely,    may    be    completely    closed.      Phimosis    may 

cause  <lijji<-uli  micturition  if  the  opening  at  the  end  of  the  prepuce  is 

very  small,  and  in  any  case  balanoposthUis  is  likely  to  occur,  which  is 
due  to  secretions  and  urine  retained  beneath  the  prepuce,  and  is  followed 

dhesions  of  the  prepuce  to  the  glans.     Incomplete  development 

of  the  glans,  vesical  ami  uii  dual  irritation  with  incontinence  of  urine, 
especially    nocturnal,    hernia,    prolapsus    recti,    and    greater    liability    to 

contract    venereal   diseases    may   also   resull    from    phimosis.     A   long 

of  reflex  nervous  conditions,  -pa-iic  palsies,  joint  deformities,  etc., 

-I'M  attributed  to  the  same  cause,  often  without  sufficient  reason. 

Besides  the  congenital  form,  phimosis  may  also  be  acquired  as  the  result 

of  inflammatory  swelling,  due  to  the  presence  of  ulcers  or  balanitis 
beneath    the   prepuce. 

[ion-  conditions  re  lilting  from  phimosis,  it  requires 

appropriate  treatment.     In  man    ca  i    of  congenital  phimosis  stretching 

me  prepuce  may  be  all  that  i-  necessary,  in  others  a  little  dorsal  sht 

fficient,  while  still  other     with  a   long  narrow    foreskin  require 


462  PELVIS  AND  PERINEUM 

circumcision.  The  main  object  of  this  is  to  uncover  the  glans.  It  is  un- 
necessary, if  it  were  possible,  to  divide  the  two  preputial  layers  at  the 
same  level.  No  special  instruments  are  required.  We  divide  the  outer 
layer  at  the  proper  level,  then  slit  up  the  inner  layer,  which  covers  the 
glans,  on  its  dorsum.  Then  we  can  loosen  the  adhesions  between  the 
foreskin  and  the  glans  when  present.  We  leave  a  cuff  of  the  inner  layer 
of  varying  size  and  suture  the  two  layers,  remembering  that,  as  the  inner 
layer  is  closely  attached  around  the  neck,  the  length  of  this  cuff  determines 
the  distance  of  the  scar  from  the  cervix  and  the  end  of  the  glans,  and  that 
if  too  much  of  a  cuff  is  left,  some  degree  of  phimosis  is  sure  to  persist. 
The  region  of  the  frenum  is  the  most  vascular  (artery  of  the  frenum), 
so  that  careful  hemostasis  and  the  removal  of  any  redundant  cellular 
tissue  is  necessary  to  avoid  the  formation  of  an  awkward  fibrous  lump. 
It  is  interesting  to  note  that  shortly  before  and  usually  at  birth  the  inner 
layer  of  the  foreskin  and  the  glans  are  adherent  throughout.  Normally, 
their  separation  occurs  during  infancy  spontaneously  from  erections  or 
from  the  mechanical  retraction  in  bathing,  unless  the  prepuce  is  very 
narrow. 

When  a  foreskin,  narrow  from  birth,  or  narrow  and  inelastic  as  the 
result  of  inflammation,  is  forcibly  retracted  over  the  glans  it  may  remain 
caught  in  the  cervix  owing  to  the  difficulty  of  pulling  it  down  over  the 
corona.  The  pressure  of  the  narrowest  part,  the  preputial  margin, 
especially  if  inelastic,  causes  the  glans  to  swell,  which  decreases  the  chance 
of  reduction  and  increases  the  pressure,  so  that  sloughing  may  occur 
at  the  line  of  pressure.  This  condition,  called  paraphimosis,  demands 
relief  to  save  the  preputial  band  or  even  the  glans,  etc.,  from  sloughing. 
We  may  sometimes  replace  the  foreskin  after  reducing  the  size  of  the 
glans  by  pressure,  but  other  cases  require  a  longitudinal  incision  of  the 
constricting  band  on  the  dorsum,  from  beneath  or  above  it.  The  con- 
stricting preputial  margin  forms  a  deep  furrow,  often  ulcerated,  with 
a  swollen,  edematous  fold  of  skin  on  either  side  of  it.  The  lower  fold 
may  even  overlap  the  glans  somewhat  and  cover  a  second  furrow,  the 
coronary  sulcus,  deepened  by  the  surrounding  swelling.  In  the  median 
line,  on  the  under  surface  of  the  penis,  there  is  the  indication  of  a  median 
raphe,  continuous  with  that  of  the  scrotum,  along  which  the  coverings 
of  the  penis  are  more  or  less  adherent  together. 

The  skin  is  lined  by  a  thin  dartos,  a  muscular  layer  with  longitudinal 
fibers  continuous  with  the  dartos  of  the  scrotum.  At  the  end  of  the 
prepuce  the  muscular  fibers  are  arranged  circularly,  forming  a  kind  of 
sphincter.  The  dartos  lines  both  layers  of  the  prepuce,  between  which  is 
an  extension  of  the  loose  subcutaneous  tissue,  which  connects  the  skin  and 
dartos  loosely  with  the  fascia  penis  and  renders  the  former  so  movable. 
This  loose  tissue  accounts  for  the  sudden  and  great  swelling  that  may 
occur  in  the  prepuce  or  on  the  penis  as  the  result  of  inflammation,  edema, 
or  the  extravasation  of  blood,  urine,  etc.  The  superficial  vessels  and 
nerves  are  Contained  in  this  loose  tissue,  hence  it  should  not  be  removed 
in  circumcision.  The  skin  covering  the  neck  and  the  proximal  side  of 
the  corona  is  lined  by  this  loose  tissue,  but  there  is  no  subcutaneous 


THE  MALE  URETHRA  AND  EXTERNAL  GENITALS  463 

tissue  over  the  glans.  This  accounts  for  the  fact  that  a  chancre  on  the 
glans  shows  but  little  if  any  induration  (parchment  induration),  while 
a  chancre  on  the  neck  or  the  proximal  side  of  the  corona,  a  favorite  posi- 
tion, has  a  typical  induration  of  the  base,  due  to  the  infiltration  of  the 
subcutaneous  connective  tissue. 

The  fascia  penis  is  the  highly  elastic  fibrous  sheath  investing  the 
three  erectile  bodies  which  form  the  bulk  of  the  penis.  It  extends  as 
far  as  the  neck,  around  which  it  is  firmly  attached  to  the  erectile  bodies 
and  fuses  with  the  skin.  At  the  base  of  the  pendulous  portion  of  the 
penis  this  fascia  is  continuous  with  the  suspensory  ligament  in  front  and 
the  deep  layer  of  the  superficial  perineal  fascia  behind,  and  limits  the 
forward  extension  of  extravasations  under  the  latter  fascia.  It  covers 
the  deep  dorsal  vessels  and  the  lateral  tributaries  of  the  dorsal  vein,  by 
compressing  which  it  contributes  to  the  erection  of  the  penis,  after  this 
condition  has  once  become  established.  In  this  it  is  aided  by  those  fibers 
of  the  bulbocavernosi  and  the  ischiocavernosi  which  encircle  the  dorsum 
of  the  corpora  cavernosa  and  thus  compress  the  dorsal  vein.  The  con- 
traction of  the  compressor  urethrse  muscle  and  the  pressure  of  the 
penis  against  the  pubic  arch  by  means  of  the  ischiocavernosi  muscles 
also  compress  this  vein  and  thus  assist  in  erection  of  the  penis.  Apart 
from  these  causes  of  erection,  which  act  by  hindering  the  venous  return, 
the  vasodilator  nerves  act  by  increasing  the  arterial  supply  of  the  erectile 
bodies  through  the  dorsal  arteries,  the  arteries  of  the  bulb  and  of  the 
corpora  cavernosa.  The  spinal  centre  of  erection  is  in  the  lumbar  en- 
largement (first  three  sacral  segments)  and  may  be  stimulated  by  any 
local  irritation;  it  also  receives  exciting  and  inhibitory  stimuli  from  the 
brain.  When  the  cerebral  inhibitory  action  is  shut  off,  by  an  injury 
or  disease  of  the  spinal  cord  above  this  centre,  a  condition  of  chronic 
partial  erection,  known  as  priapism,  is  likely  to  occur. 

Besides  the  active  erection,  in  which  arterial  supply  and  venous  re- 
turn are  both  concerned,  there  may  be  a  passive  erection,  such  as  that 
due  to  the  pressure  of  a  full  bladder  on  the  venous  plexus  (prostatico- 
vesical)  through  which  the  dorsal  vein  of  the  penis  empties  into  the 
branches  of  the  internal  iliac  vein.  The  proposal  to  tie  the  dorsal 
vein  to  assist  an  incomplete  erection  of  the  penis  has  been  tried  with 
some  success.  A  constricting  band  around  the  penis  causes  rapid  and 
extensive  swelling  of  the  organ,  hence  in  tying  in  a  catheter  it  is  best  not 
to  employ  tapes  around  the  penis,  and  no  bandage  around  the  penis 
should  be  tight.  The  large,  deep  dorsal  vein  (Fig.  159)  of  the  penis  is 
usually  single  and  occupies  the  groove  between  the  two  corpora  caver- 
nosa superiorly.  It  pierces  the  triangular  ligament  12  mm.  (^  in.)  below 
the  pubic  arch.  The  thick,  elastic  sheath  of  the  corpora  cavernosa, 
called  the  tunica  albuginea  from  its  whitish  appearance,  consists  of  an 
outer  layer  of  longitudinal  fibers  covering  both  corpora  and  an  inner  layer 
of  circular  fibers  forming  a  separate  sheath  for  each.  The  latter  forms 
a  septum  between  the  two  which  is  incomplete  anteriorly,  so  that  any 
inequality  in  the  blood  supply  of  the  two  corpora  may  be  equalized. 

The  suspensory  ligament  of  the  penis  connects  the  corpora  cavernosa 


464  PELVIS  AND  PERINEUM 

with  the  front  of  the  symphysis  pubis.  In  front  of  this  ligament  we 
have  the  movable  portion  or  "body"  of  the  penis,  which  serves  as  the 
pars  copulatrix  and  corresponds  to  the  pars  mobilis  of  the  urethra. 
The  angle  of  the  penis,  immediately  in  front  of  the  suspensory  liga- 
ment, is  only  present  in  the  flaccid  condition  of  the  organ.  In  erec- 
tion the  "body"  of  the  penis  comes  into  line  with  the  "root,"  which 
corresponds  to  the  two  crura  of  the  corpora  cavernosa  which,  diverging 
behind  the  suspensory  ligament,  are  attached  to  the  ischiopubic  rami. 

Each  corpus  cavernosum  measures  about  15  x  1.2  cm.  (6  x  \  in.), 
which  increases  by  a  third  or  more  in  erection.  The  corpus  spongiosum 
begins  behind  in  an  enlargement,  the  bulb,  surrounding  the  floor  and  sides, 
and,  farther  forward,  the  entire  urethra.  It  ends  in  front  in  a  conical 
cap,  the  glans  penis,  which  covers  the  rounded  anterior  extremities  of 
the  corpora  cavernosa.  The  bulb,  measuring  3.7  cm.  (1J  in.)  long  and 
18  mm.  (f  in.)  broad,  abuts  against  the  central  point  of  the  perineum, 
2.5  to  3.5  cm.  (1  to  1^  in.)  in  front  of  the  anus.  It  presents  inferiorly 
an  incomplete  median  septum,  indicated  on  the  surface  by  a  slight 
furrow;  hence  if  the  bulb  is  incised  in  the  exact  median  line  the  bleeding 
is  less  than  it  otherwise  would  be.  The  bulb  is  invested  by  a  fibro- 
muscular  sheath,  continuous  with  the  superficial  layer  of  the  triangular 
ligament,  and  by  the  bulbocavernosus  muscle,  whose  action  assists  in 
ejaculation,  in  expelling  the  last  drops  of  urine,  and  in  the  erection  of  the 
penis.  The  glans  is  twice  as  long  on  its  upper  as  on  its  under  surface, 
and  its  projecting  base  or  corona,  which  limits  the  neck,  is  interrupted 
in  the  median  line  inferiorly  by  a  small  median  fold,  the  frenum  preputii, 
continuous  with  the  inner  layer  of  the  prepuce.  The  frenum  grooves 
the  under  surface  of  the  glans  as  far  as  the  inferior  angle  of  the  meatus, 
and  contains  vessels  of  some  size  which,  if  ruptured  in  coitus,  in  case 
the  frenum  is  unusually  short,  or  eroded  by  chancroidal  ulceration,  may 
cause  considerable  loss  of  blood.  They  may  require  hemostasis  in  cir- 
cumcision. In  erection  both  the  glans  and  the  rest  of  the  corpus  spon- 
giosum are  soft  as  compared  with  the  corpora  cavernosa,  and  thus  they 
offer  no  resistance  to  the  passage  of  semen  or  urine. 

When  a  urethritis  extends  beyond  the  mucosa  and  causes  an  indura- 
tion of  the  submucous  structures,  or,  still  further,  to  the  trabecular  of  the 
corpus  spongiosum,  and  the  spaces  of  the  erectile  tissue  become  filled  by 
an  exudate,  the  corpus  spongiosum  loses  its  elasticity,  so  that  in  erection 
it  cannot  elongate,  but  acts  like  the  string  of  a  bow  and  bends  down  the 
corpora  cavernosa,  so  that  the  erected  penis  is  curved  backward.  This 
condition,  known  as  chordee,  is  very  painful,  owing  to  the  traction  on  the 
inflamed  urethra  and  corpus  spongiosum.  The  erected  corpora  cavernosa 
may  be  "fractured"  by  forcible  flexion  in  coitus  and  otherwise.  Such  an 
injury  is  irreparable;  it  causes  an  extravasation  of  blood,  interrupts  the 
continuity  of  the  erectile  tissue,  so  that  erection  in  front  of  the  break  is 
impossible,  and  it  prevents  the  straight  erection  of  the  penis,  for  the  corpus 
cavernosum  so  affected  can  not  lengthen  as  much  as  the  other;  or  if 
both  are  affected,  the  portion  of  both  distal  to  the  break  cannot  become 
erected, 


THE  MALI-:   URETHRA    AND   EXTERNAL  GENITALS  Hi.-) 

Lymphatics. — The  lymphatics  of  the  penis,  including  those  of  the 
urethral  mucosa,  enter  the  middle  group  of  the  superficial  inguinal 
lymph  nodes.  Those  from  the  glans  enter  the  deep  inguinal  and 
lowermost  iliac  nodes.  As  cancer  of  the  penis  commonly  originates 
in  the  glans,  the  deep  nodes  may  he  involved  as  soon  as  or  before  the 
superficial  nodes.  The  lymph  trunks  pass  up  the  dorsum  of  the  penis, 
where  they  may  be  felt  in  lympangitis. 

Congenital  Malformations. — Hypospadias,  the  commonest  form,  is 
due  to  a  partial  or  complete  failure  to  unite,  on  the  part  of  the  genital 
folds,  on  the  under  aspect  of  the  penis.  These  folds  by  their  union 
convert  the  groove  between  them  into  the  spongy  portion  of  the  urethra. 
This  failure  to  unite  may  affect  the  entire  length  of  the  spongy  urethra, 
so  that  the  urethral  opening  is  in  the  perineum;  or  it  may  occur  at 
the  end  and  involve  only  the  glans,  so  that  the  opening  is  just  back  of 
the  glans;  or  it  may  occur  at  any  intermediate  point.  In  complete 
hypospadias,  and  to  a  less  extent  in  other  forms,  the  corpus  spongiosum 
is  wanting  or  defective,  being  replaced  largely  by  fibrous  tissue  which 
does  not  lengthen  in  erection  of  the  penis,  so  that  in  this  condition  the 
penis  is  bent  sharply  downward  and  backward.  Complete  hypospadias 
is  often  accompanied  by  a  cleft  scrotum  and  perhaps  by  an  empty 
scrotum,  and  is  then  one  of  the  elements  which  go  to  make  up  pseudo- 
hermaphroditism. 

Epispadias  is  due  to  a  failure  of  more  or  less  of  the  urethra  to  close  on 
its  upper  aspect.  The  opening  is  usually  found  in  front  of  the  symphysis, 
and  the  condition  is  often  associated  with  a  separation  of  the  symphysis 
and  exstrophy  of  the  bladder;  hence  it  is  due  to  malformation  at  an  early 
period  of  development.     It  is  more  difficult  to  explain  cmbryologically. 

Besides  being  the  most  frequent  situation  for  chancroid,  condylo- 
mata, and  the  initial  lesion  of  syphilis,  the  distal  portion  of  the  penis 
may  be  affected  by  cancer.  This  commonly  takes  the  form  of  epithe- 
lioma of  the  glans  or  prepuce,  and  most  cases  are  said  to  occur  when 
phimosis  exists  or  has  existed.  The  inguinal  nodes  may  be  involved 
early,  ami  should  always  be  removed.      (See   Lymphatics,  above.) 

The  Scrotum.  -Although  in  descriptive  anatomy  this  term  is  often 
applied  lo  the  skin  and  darlos  only,  yet  topographically  we  must  con- 
sider with  it   the  other  envelopes  of  the  testicle  and  of  the  lower  part  of 

the  spermatic  cord.    The  lax  scrotum  is  admirably  suited  t<>  protect  the 

testicles  by  allowing   them  to  move  about  SO  readily  and  thus  to  escape 

injury.     The  lift  half  is  commonly  larger  than  the  right.     Iii  the  infant 

POtum  i-  larger  above  than  below,  vice  versa  in  the  adult.      It  will 

be  noticed  thai  the  layers  of  the  scrotum  correspond  to  those  covering 
the  sac  of  an  oblique  inguinal  hernia.  • 

The  skin  is  thin  and  transparent,  showing  an  ecchymosis  beneath  it 
ipiiekly  arid  distinctly.  It  is  very  clastic,  so  thai  it  allows  of  great  dis- 
tention, as  in  large  hernue,  hydroceles,  and  tumors.  It  is  also  redundant, 
10  thai  tin-  l<»  of  ;i  portion  by  excision  or  sloughing  will  not  be  missed. 
Excision  of  redundant  scrotum  has  been  employed  in  the  treatment  of 
varicocele.     The    kin  forms  a  tingle  VOUch,  but  a  median  raphe,  continu- 


466  PELVIS  AND  PERINEUM 

ous  with  that  on  the  under  surface  of  the  penis  and  in  the  perineum, 
indicates  its  embryological  formation  from  two  lateral  halves.  The 
more  or  less  transverse  rugce,  into  which  the  skin  is  thrown  by  the  con- 
traction of  the  underlying  dartos,  favor  the  accumulation  of  dirt  and 
the  secretions  of  the  sweat  and  sebaceous  glands,  the  irritation  due  to 
which  may  account  for  the  eczema  and  epitheliomata  not  uncommon 
here. 

The  dartos  is  very  vascular  and  closely  lines  the  skin,  especially  in 
the  lower  part  of  the  scrotum.  Its  dark  reddish  color  depends  upon 
the  longitudinally  disposed  unstriped  muscle  fibers  that  it  contains, 
the  contraction  of  which  causes  the  transverse  rugce  of  the  skin.  These 
rugse  are  a  sign  of  health;  they  disappear  in  old  age,  in  enfeebled  con- 
ditions, or  under  the  relaxing  effects  of  heat,  and  the  scrotum  becomes 
smooth  and  pendulous.  Warm  applications  relax  the  dartos,  and  thus 
may  prevent  the  inversion  of  the  edge  of  an  incised  wound  of  the  scrotum, 
which  interferes  with  its  proper  suture.  In  wounds  of  the  scrotum, 
especially  with  loss  of  substance,  the  contraction  of  the  dartos  is  of  value 
in  closing  the  gap.  Such  a  contraction  may  be  stimulated  by  cold  appli- 
cations, sexual  excitement,  mental  emotions,  and  by  slight  friction,  but 
not  by  electricity.  Its  contraction  is  slow  and  peristaltic,  and  shortens 
the  scrotal  pouch.  The  scrotum,  after  the  cure  of  hydrocele  or  hernia, 
is  enabled  to  regain  its  normal  size  by  the  contractility  of  this  tissue. 
The  dartos  forms  a  separate  pouch  for  each  testis,  and  the  median  meeting 
of  these  two  sacs  forms  the  septum  scroti,  which  extends  from  the  raphe 
of  the  skin  to  the  root  of  the  penis.  The  dartos  is  continuous  with  the 
superficial  fascia  of  the  abdomen  and  perineum  and  with  the  dartos  of 
the  penis,  and,  like  the  latter,  contains  no  fat. 

The  skin  and  dartos  form  practically  a  single  layer,  connected  by  a 
loose  connective-tissue  layer  with  a  composite  layer  formed  by  the  other 
envelopes  of  the  testicle,  etc.  For  practical  and  surgical  purposes  the 
testis,  etc.,  is  covered  by  only  two  composite  layers,  loosely  united  by 
this  loose  connective-tissue  layer.  This  loose  fatless  connective  tissue 
layer  allows  large  extravasations  of  blood  to  occur  after  injuries.  Owing 
to  the  dependent  position  of  the  scrotum,  this  tissue  may  early  become 
very  edematous  in  a  case  of  dropsy.  It  allows  the  testis  and  cord  and 
their  envelopes  to  be  enucleated  through  an  incision  or  protruded 
through  a  wound  of  the  scrotum  proper.  It  is  continuous  with  a 
similar  layer  in  the  penis,  and  thus  extravasations  of  urine  or  of  any 
sort  may  readily  extend  from  the  scrotum  to  the  penis,  and  vice  versa. 
By  some  this  layer  is  regarded  as  continuous  with  the  intercolumnar 
fascia  at  the  external  ring,  and  hence  as  being  the  external  spermatic 
fascia,  while  others  describe  the  latter  as  more  membranous  and  as 
forming  a  fascial  covering  of  the  cremaster  muscle,  most  distinct  above. 

The  cremasteric  and  infundibuliform  layers,  continuous  in  the  inguinal 
canal  with  the  internal  oblique  muscle  and  the  infundibuliform  fascia 
respectively,  are  lined  by  the  parietal  layer  of  the  tunica  vaginalis  and 
form  a  composite  envelope  for  the  testis.  This  envelope  is  connected 
by  the  loose  connective-tissue  layer  with  the  scrotum  proper,  and  hence 


THE  MALE  URETHRA  AND  EXTERNAL  GENITALS  467 

is  readily  separable  from  the  latter,  except  at   the  scrotal  ligament, 
inferiorly. 

The  cremaster  is  a  voluntary  muscle  occurring  in  scattered,  arched 
bundles,  bound  together  by  thin,  connective- tissue  laminae,  which  also 
form  the  sheaths  of  the  muscular  bundles.  These  bundles  lie  mostly 
in  front  of  and  below  the  sac  formed  by  the  next  layer.  It  is  supplied  by 
the  genital  branch  of  the  genitocrural  nerve.  Its  contraction  suddenly 
raises  the  testis  and  its  inner  coverings  within  the  scrotal  pouch.  The 
cremasteric  reflex  is  the  reflex  contraction  of  this  muscle  following  stimu- 
lation, as  by  scratching,  of  the  skin  of  the  upper  and  anterior  aspect 
of  the  thigh,  which  is  supplied  by  the  sensory  or  crural  branch  of  this 
nerve.  The  muscle  becomes  hypertrophied  when  the  size  or  weight  of 
the  enclosed  mass  is  increased,  as  in  large  hernia?,  etc.  According  to 
Toldt,  its  contraction  favors  the  venous  circulation  within  the  scrotum 
and  helps  to  press  out  the  contents  of  the  epididymis. 

The  infundibuliform  fascia  {internal  spermatic  fascia),  by  its  direct 
connection  with  the  lower  part  of  the  posterior  border  of  the  testis, 
anchors  the  latter  in  the  postero-inferior  part  of  the  scrotum,  so  that  it 
retains  this  position  when  the  cavity  of  the  tunica  vaginalis  is  filled  with 
the  fluid  of  a  hydrocele  or  a  hematocele.  Hence  we  puncture  a  hydro- 
cele  in  front  and  above,  to  be  out  of  reach  of  the  testis.  At  the  point 
of  attachment  of  the  testis  the  infundibuliform  fascia  is  also  adherent 
to  the  external  layers,  and  is  assisted  in  anchoring  the  testis  by  a  fibro- 
museular  band,  the  scrotal  ligament,  which  represents  the  remains  of 
the  gubernaculuni  testis,  connecting  the  lower  end  of  the  epididymis 
with  the  scrotal  wall. 

Loose  areolar  tissue,  continuous  with  the  subperitoneal  connective  tissue, 
connects  the  infundibuliform  fascia  with  the  tunica  vaginalis  and  binds 
together  the  various  elements  of  the  spermatic  cord.  In  the  latter  situa- 
tion it  contains  some  fat,  and  is  the  seat  of  the  fatty  tumors  of  the  cord, 
which  occasionally  simulate  an  inguinal  hernia.  This  layer,  together 
with  the  infundibuliform  fascia,  is  known  as  the  fascia  propria  of  Cooper, 
who  described  it  as  very  strong  in  large,  old  hernia?.  A  muscular  band 
in  this  subserous  layer  (middle  cremaster)  is  said  sometimes  to  groove 
a  hydrocele  so  as  to  partly  divide  it.  The  parietal  layer  of  the  tunica 
vaginalis  extends  for  12  mm.  (£  in.)  above  the  level  of  the  testis,  form- 
ing a  cul-de-sac  at  the  beginning  of  the  cord. 

The  two  composite  layers  of  the  coverings  of  the  testis  have  a  sepa- 
rate blood  supply,  with  anastomoses  between  (lie  two  layers,  and  with 
the  blood  supply  of  the  testis,  in  the  scrotal  ligament  at  the  base  of  the 

otum.     Tin-  anastomosis  between  die   two   halves  of  the   scrotum 

a  quite  free.     The  skin  and  dartos  arc  supplied  by  the  pudic  vessels 

ternal  pudic  and  the  superficial  branch  of  the  internal  pudic),  the 

envelopes    of    the    testicle    by    the   cremasteric   vessels.     Although    the 

i  rv  '.a  cular,  Its   vitality  is  not.  great,  so  that  it  may  slough 

from    evere  inflammation  or  pressure,  hence  strapping,  if  employed 

al  all,  should  be  applied  with  care,  for  it  has  been  followed  by  extensive 
sloughing.     The    large,   superficial,  and    often    tortuous    veins   of    the 


468  PELVIS  AND  PERINEUM 

scrotum,  which  are  visible  through  the  skin,  should  be  avoided  in  tapping 
a  hydrocele.  They  end  in  the  internal  saphenous  vein,  but  communicate 
with  the  spermatic  veins. 

The  lymphatics  of  the  scrotum  pass  to  the  supero-internal  and  the 
inferior  groups  of  superficial  inguinal  lymph  nodes.  These  nodes  are 
involved  in  diseases  of  the  testicle,  as  a  rule,  only  when  the  scrotum  is 
also  involved.  Elephantiasis,  a  disease  marked  by  great  hyperplasia  of 
connective  tissue  and  due  to  the  irritation  of  filaria  in  the  lymph  vessels, 
occurs  most  frequently  in  the  scrotum.  The  skin  and  dartos  receive 
their  nerve  supply  from  the  internal  pudic  and  small  sciatic  nerves, 
etc.;  the  ilio-inguinal  and  the  genitocrural  do  not  supply  the  skin  of 
the  scrotum  (Cushing).  Embryologically,  the  scrotum,  like  the  labia 
majora,  is  formed  by  the  genital  ridge,  the  two  sides  of  which  unite 
together  mesially  to  form  the  scrotum.  Failure  of  this  union  is  one  of 
the  features  of  so-called  hermaphroditism  in  certain  of  its  forms.  In 
these  cases  the  ununited  halves  of  the  scrotum  resemble  the  labia. 

The  Testis. — Position  (Fig.  160). — The  testes  are  normally  situated  in 
the  lower  end  of  each  half  of  the  scrotal  pouch,  where  they  are  suspended 
by  the  spermatic  cords  at  unequal  levels,  the  left  being  commonly  lower 
than  the  right,  owing  to  the  greater  length  of  the  left  spermatic  cord. 
This  enables  the  testes  to  avoid  pressure  from  each  other.  The 
testis  is  held  in  position  and  anchored  to  the  postero-inferior  part  of 
the  scrotum  by  the  scrotal  ligament,  by  its  attachment  to  the  infun- 
dibuliform  fascia  along  the  lower  part  of  its  posterior  or  straighter 
border,  and  by  the  reflection  of  the  visceral  layer  of  the  tunica  vaginalis 
to  join  the  parietal  layer  postero-inferiorly.  Hence  when  the  vaginal 
sac  is  filled  with  fluid,  as  in  hydrocele  or  hematocele,  the  testis  occupies 
a  postero-inferior  position  in  the  sac,  and  we  can  safely  puncture  the  sac 
in  front  or  above.  In  some  cases  the  testis  is  rotated  on  its  vertical  axis 
and  attached  antero-inferiorly  (inversion  of  the  testis),  but  in  such  a  case 
we  can  still  safely  tap  a  hydrocele  above  and  in  front  or  at  the  side. 
In  other  cases  the  testis  may  lie  horizontally  with  the  epididymis  above 
or  below  (Kocher).  Torsion  of  the  testis  and  cord  in  either  direction 
on  the  longitudinal  axis  is  an  uncommon  accident,  which  may  cause 
merely  an  infiltration  of  the  epididymis  or,  if  severe,  gangrene  of  the 
testis,  etc.  It  probably  depends  upon  a  congenital  malformation  or 
partial  descent  of  the  testis,  as  a  normally  placed  testis  cannot  be  twisted. 

Development  and  Descent. — In  early  fetal  life  the  testis  is  developed 
internal  to  the  lower  end  of  the  kidney  at  the  level  of  the  first  and  second 
lumbar  vertebrae,  hence  the  origin  of  the  spermatic  vessels  in  this  region. 
It  lies  behind  the  peritoneum,  or  with  a  short  mesentery  of  peritoneum 
(mesorchium),  and  to  its  lower  end  is  attached  a  fibromuscular  band, 
the  gubernaculum  testis  (rudder  of  the  testis),  whose  three-tailed  lower 
end  is  attached  to  the  dartos  at  the  bottom  of  the  scrotum  and  to  the 
two  pillars  of  the  external  abdominal  ring.  Beginning  to  descend  in  the 
second  month  of  fetal  life,  it  retains  a  position  near  the  internal  ring 
from  the  end  of  the  third  to  the  end  of  the  sixth  month.  Then,  preceded 
by  a  pouch  of  peritoneum  from  this  part  (processus  vaginalis),  which 


THE  MALE  URETHRA   AND  EXTERNAL  GENITALS  469 

pushes  before  it  a  sheath  from  each  of  the  layers  of  the  abdominal  wall 
through  which  it  passes,  the  testis  reaches  the  external  ring  at  the  eighth 
month  and  the  bottom  of  the  scrotum  shortly  before  birth,  but  occa- 
sionally not  until  after  birth.  Hence  the  presence  of  the  testis  in  the 
scrotum  is  an  indication  of  the  maturity  of  a  male  fetus.  The  cause 
of  this  "descent  of  the  testis"  is  uncertain,  but  it  is  probably  partly  due 
to  the  development  of  the  pelvic  and  lumbar  regions,  which  grow  upward 
away  from  the  testis,  anchored  by  the  gubernaculum,  and  partly  to  the 
contraction  or  atrophy  of  the  latter,  for  the  first  cause  would  not  take 
it  beyond  the  internal  ring  at  most. 

One  or  both  testes  may  be  arrested  in  their  descent  in  the  abdomen, 
at  the  internal  ring,  in  the  inguinal  canal,  or  just  outside  of  the  latter. 
When  the  testes  have  not  passed  the  external  ring  the  condition  is  called 
ectopia  testis  or  cryptorchism  (normal  in  certain  animals,  elephants,  etc.), 
which  may  be  unilateral  or  bilateral.  Inguinal  retention  (i.  e.  in  the  in- 
guinal canal)  is<*he  commonest  form.  Retention  of  the  testes  has  been 
attributed  to  adhesions  from  prenatal  peritonitis,  shortness  of  the  cord, 
and  small  size  of  the  external  ring.  The  vas  often  descends  below  the 
testes  and  then  turns  back  to  reach  the  latter.  A  testis  arrested  within 
the  canal  may,  and  one  at  the  external  ring  usually  does,  reach  the 
scrotum  at  or  before  puberty.  A  testis  retained  above  the  external 
ring  is  atrophic,  and  is  said  not  to  be  functionally  active;  hence  it  may 
be  removed  without  question  in  an  operation  when  it  complicates  a 
hernia.  It  is  also  said  to  be  especially  liable  to  malignant  disease,  but 
the  statement  is  supported  by  little  proof.  If  it  is  lodged  in  the  inguinal 
canal  it  may  be  mistaken  for  and  it  predisposes  to  a  hernia,  and  is  sub- 
ject to  attacks  of  inflammation  from  pressure  or  injury.  Such  an  in- 
flamed testis  may  cause  errors  in  diagnosis,  being  mistaken  for  abscess, 
strangulated  hernia,  etc.,  unless  it  is  noticed  that  the  testis  of  that  side 
is  wanting  in  the  scrotum.  Again  the  testis  may  become  aberrant  and 
descend  into  the  groin  through  the  femoral  instead  of  the  inguinal  canal 
(femoral  ectopy),  or  it  may  wander  into  the  perineum  (perineal  ectopy). 
Exceptional  attachments  or  irregular  development  of  the  gubernaculum 
account  for  some,  at  least,  of  the  cases  of  ectopy  of  the  testis. 

The  consistence  of  the  testis  is  firm  and  elastic,  more  so  when  the 
tubules  arc  full  or  in  certain  diseases,  such  as  tuberculosis,  syphilis,  or 
tumors,  less  so  before  puberty  or  when  atrophy  occurs  from  old  age  or 
otherwise.  The  consistence  is  normally  uniform  and  the  surface  should 
be  smooth,  so  that  when  nodules  or  localized  hardening  or  softening  occur 
the  testis  is  abnormal  or  diseased.  Partial  induration  of  the  epididymis 
indicates  tuberculosis  or  a  chronic  following  an  acute  inflammation 
(epididymitis). 

The  normal  size  il  cm.  (Ij  in.]  in  length,  3  cm.  [1{  in.]  in  depth,  and 
:i  little  less  than  2.5  cm.  [1  in.]  in  thickness)  and  the  normal  weight 
5  to  8 drams)  arc  not  attained  until  after  puberty,  being  much  less  before 
then.  It'  then-  is  only  one  testis  (monorchism),  an  occasional  occurrence, 
or  only  one  descended,  its  size  and  weight  may  be  much  increased,  other- 
wise such  increase  indicates  a  pathological  condition. 


470  PELVIS  AND  PERINEUM 

The  great  thickness  (1  mm.)  of  its  bluish-white  fibrous  covering, 
tunica  albuginea,  prevents  any  sudden  expansion,  but  allows  a  gradual 
increase  in  size,  as  in  tumors  or  chronic  inflammation.  This  accounts 
for  the  intense  pain  in  acute  orchitis,  due  to  pressure  on  the  nerve 
endings  by  the  products  of  inflammation  pent  up  within  the  unyielding 
capsule.  If  in  such  a  case  the  inflammation  is  purulent  and  an  opening 
occurs  in  the  tunica  albuginea,  the  tension  of  the  inflammatory  products 
forces  out  the  substance  of  the  testis,  and  we  have  hernia  or  fungus  testis, 
which  may  go  on  even  until  all  the  testicular  substance  is  extruded  and 
only  granulation  tissue  remains.  This  condition  is  due  to  the  firmness 
of  the  fibrous  capsule.  The  pain  of  an  epididymitis,  on  the  other 
hand,  is  much  less,  as  the  fibrous  covering  of  the  epididymis  is  much 
less  thick  and  firm  and  more  elastic  and  yielding,  so  that  this  part  may 
swell  rapidly  and  extensively. 

The  chief  relations  of  the  testis  are  with  its  covering,  the  visceral 
layer  of  the  tunica  vaginalis,  with  the  epididymis,  and  with  the  cord. 
The  testis  is  completely  covered  by  the  visceral  layer  of  the  tunica 
vaginalis,  except  along  its  posterior  border,  where  superiorly  the  effer- 
ent tubules  pass  out  into  the  head  of  the  epididymis,  below  this  the 
vessels  enter,  and  inferiorly  the  border  is  adherent  to  the  infundibuliform 
fascia  and  attached,  either  directly  or  through  the  lower  end  of  the 
epididymis,  to  the  scrotal  ligament.  Along  this  posterior  border  the 
visceral  layer  of  the  tunica  vaginalis  is  continuous  with  the  parietal 
layer,  either  directly,  as  on  the  mesial  side,  or  after  partly  covering  the 
epididymis,  as  on  the  lateral  side. 

Normally  the  two  serous  layers  are  in  contact,  separated  by  only 
enough  fluid  to  moisten  or  lubricate  them.  An  increase  of  the  amount 
of  this  fluid,  which  may  reach  several  ounces  or  even  pints,  constitutes 
a  hydrocele  or,  if  the  fluid  is  largely  bloody,  a  hematocele.  A  hydro- 
cele is  pear-shaped,  with  the  small  end  above,  and  is  commonly  trans- 
lucent, except  where  the  testis  lies,  the  normal  position  of  which  we 
have  seen  above. 

The  upper  tubular  portion  of  the  processus  vaginalis  usually  atro- 
phies soon  after  birth  to  a  mere  fibrous  band  (vaginal  ligament),  which 
lies  among  the  elements  of  the  spermatic  cord  and  which  we  can  some- 
times trace  from  the  bottom  of  the  slight  depression  of  the  peritoneum 
at  the  internal  ring  to  the  upper  end  of  the  vaginal  pouch.  Sometimes, 
however,  this  upper  tubular  portion  remains  open  (see  p.  295),  in  whole 
or  in  part.  If  the  entire  "processus"  remains  open,  fluid  may  pass 
into  it  from  the  peritoneum,  or  may  be  returned  into  the  latter  by  pressure 
or  posture.  It  would  be  unsafe  to  inject  irritant  fluids  into  such  a  con- 
genital hydrocele,  owing  to  its  connection  with  the  peritoneal  cavity. 
If  the  processus  is  closed  above  and  below,  or  at  intervals,  and  is  open 
between,  fluid  collecting  in  the  unclosed  portions  above  the  vaginal 
pouch  constitutes  an  encysted  hydrocele  of  the  cord,  either  monolocular 
or  multilocular.  Such  hydroceles,  like  the  processus  vaginalis  in  which 
they  are  formed,  lie  in  front  of  the  cord,  and  the  testis  can  be  plainly 
felt  below  the  swelling  if  there  is  no  vaginal  hydrocele  as  well.     An 


THE  MALE  URETHRA  AND  EXTERNAL  GENITALS  471 

encysted  hydrocele  in  the  canal  of  Xuck,  which  is  occasionally  met  with, 
occurs  in  the  similar  process  of  peritoneum  in  the  female. 

The  Epididymis. — The  epididymis  (Fig.  161)  rests  upon  the  posterior 
border  and  overlaps  the  adjoining  portion  of  the  external  surface  of 
the  testis.  Its  enlarged  upper  end  or  head,  globus  major,  projects  above 
the  upper  extremity  of  the  testis,  where  it  is  readily  felt.  It  is  intimately 
connected  with  the  upper  end  of  the  posterior  border  by  the  visceral  layer 
of  the  tunica  vaginalis,  which  covers  it,  and  by  the  vasa  efferentia  which, 
coiled  up  as  the  coni  vasculosi,  form  the  great  bulk  of  the  globus  major. 
Between  the  body  of  the  epididymis  and  the  outer  surface  of  the  testis 
is  a  small  fossa,  the  digital  fossa,  lined  by  the  tunica  vaginalis.  On 
account  of  its  meso-epididymis,  connecting  the  body  of  the  epididymis 
with  the  posterior  border  of  the  testis,  the  former  is  readily  movable 
and  may  be  pressed  away  from  the  testis  and  even  more  or  less  trans- 
versely placed,  after  stretching  of  this  serous  duplicature  in  large 
hydroceles,  etc. 

The  lower  and  somewhat  enlarged  end  or  tail,  globus  minor,  reaches 
nearly  to  the  lower  limit  of  the  posterior  border  of  the  testis,  to  which 
it  is  loosely  connected.  The  tunica  vaginalis  leaves  uncovered  most 
of  the  tail,  the  posterior  part  of  the  inner  surface  of  the  body,  and  the 
posterior  border  of  the  epididymis.  Along  the  latter  border  and  the 
mesial  part  of  the  posterior  border  of  the  testis  the  visceral  is  continuous 
with  the  parietal  layer  of  the  tunica  vaginalis  by  means  of  two  folds, 
between  which  the  vessels  pass  to  and  enter  the  posterior  borders  of 
each  organ.  The  globus  minor  is  continuous  with  the  vas  deferens, 
hence  inflammation  reaching  the  epididymis  along  the  vas  should  first 
affect  this  part.  The  smaller  size  and  more  tortuous  course  of  the 
arteries  of  the  epididymis  appear  to  account  for  the  relative  frequency 
of  its  involvement  in  general  infections.  From  its  greater  size  when 
inflamed  and  swollen  the  globus  major  is  much  the  most  prominent  part 
in  epididymitis.  Most  of  the  cases  of  so-called  swollen  testis  following 
a  gonorrheal  posterior  urethritis,  the  passage  of  an  instrument,  etc., 
are  really  cases  of  epididymitis,  the  testis  remaining  unaffected.  The 
hard  and  much  enlarged  epididymis  can  be  felt  overlapping  and  mask- 
ing the  testis  behind,  above,  and  more  or  less  externally,  while  the 
testis  is  normal  in  size  and  consistence.  Tuberculosis  commonly 
;if  tacks  primarily  and  often  exclusively  the  epididymis,  tertiary  syphilis 
tli<-  testis. 

The  Arterial  Supply. — The  arterial  supply  of  the  testis  is  from  the 
|><  rrnatic  artery  with  some  anastomotic  supply  from  the  artery  of  the 
The  veins  enter  the  spermatic  or  pampiniform  plexus.  When 
varicosity  of  this  plexus  occurs  before  adolescence,  or  when  it  exists 
for  a  long  lime,  it  may  cau  <  atrophy  of  the  testis.  The  elevation  of  the 
.linn,  practised  in  nil  inflammations  of  the  epididymis  and  the  testis, 
by  diminishing  the  congestion  by  favoring  the  venous  but  not  the 
arterial  circulation.  Tin-  lymphatics  enter  the  Lumbar  nodes.  Tin;  rare 
instances  where  affections  of  tin-  testis  involve;  tin;  inguinal  nodes,  with- 
out, first  involving  the  scrotal  coverings,  are  to  be  explained  by  lymphatic 


472  PELVIS  AND  PERINEUM 

anastomoses  accompanying  the  vascular  anastomoses  which  we  know 
are  present  along  the  scrotal  ligament,  etc. 

The  Nerve  Supply. — The  association  of  the  spermatic  plexus,  accom- 
panying the  spermatic  artery  and  derived  from  the  renal  and  aortic 
plexuses,  with  the  abdominal  sympathetic  nerve  centres  explains  (1)  the 
pain  in  and  retraction  of  the  testis  during  the  passage  of  a  renal  calculus, 
and  (2)  the  sickening  pain,  nausea,  faintness,  and  collapse  or  syncope 
which  result  from  a  blow  on  or  inflammation  (orchitis)  of  the  testis. 
The  pain  from  such  a  blow  extends  into  the  loins,  and  pain  in  the  back, 
often  felt  in  orchitis,  after  the  injection  of  a  hydrocele  or  from  the  drag- 
ging of  a  tumor  of  the  testis,  depends  upon  the  fact  that  its  chief  source 
of  innervation  is  the  tenth  thoracic  segment.  The  sickening  pain 
due  to  slight  pressure  on  the  testis  is  so  characteristic  as  to  be  diag- 
nostically  useful  in  determining  the  presence  or  position  of  the  testis 
in  a  swelling  in  the  inguinal  region  or  scrotum.  Pressure  on  the  ovary 
causes  a  somewhat  similar  pain. 

Fetal  Remains. — Two  structures  go  under  the  name  of  hydatids  of 
Morgagni:  (1)  a  pediculated,  pear-shaped,  serous  sac  filled  with  a  clear 
fluid,  attached  to  the  upper  pole  of  the  globus  major  and  not  always 
present,  and  (2)  a  fairly  constantly  present  sessile,  flattened,  and  often 
lobulated  structure,  containing  in  its  centre  a  canal  which  may  end 
blindly  or  on.  the  surface.  The  sessile  hydatid  is  attached  to  the  upper 
end  of  the  testis,  in  front  of  the  globus  major,  and  represents  the  end 
of  the  duct  of  Miiller;  hence  it  is  homologous  with  the  fimbriated  ex- 
tremity of  the  Fallopian  tube.  The  paradidymis,  or  organ  of  Giraldes, 
probably  derived  from  the  tubules  of  the  Wolffian  body,  usually  disap- 
pears in  early  childhood.  It  appears  as  a  yellowish-white  patch,  which 
lies  outside  of  the  parietal  layer  of  the  tunica  vaginalis,  on  the  lower  part 
of  the  spermatic  cord,  in  front  of  the  spermatic  plexus,  and  posterior 
to  the  globus  major. 

;  The  above  fetal  remains,  together  with  the  vas  aberrans,  are  of  prac- 
tical importance  because  they  may  give  rise  to  cystic  tumors,  including 
the  true  spermatic  cysts  containing  seminal  fluid.  The  latter  are  most 
often  formed  from  the  tube  of  the  epididymis,  especially  the  globus 
major.  The  above  cysts  may  project  free  into  the  cavity  of  the  tunica 
vaginalis. 

In  addition  to  tuberculosis  and  syphilis  the  testis  may  be  the  seat  of 
almost  any  newgrowth  except  lipoma.  Sarcoma  and  chondroma  are 
particularly  common,  and  tumors  of  the  testis,  like  those  of  the  parotid, 
are  very  liable  to  be  "mixed,"  consisting  of  several  kinds  of  newgrowth. 
Newgrowths  usually  spring  from  the  testis  proper,  seldom  from  the  epi- 
didymis. Removal  of  the  testes  diminishes  the  size  of  the  prostate,  which 
is  much  atrophied  in  eunuchs;  hence  the  employment  of  castration  in 
the  treatment  of  hypertrophy  of  the  prostate,  but  the  result  appears  to 
be  only  temporary.  As  division  of  the  vas  deferens  causes  atrophy 
of  the  testis,  it  has  also  been  employed  for  the  same  purpose. 

The  Spermatic  Cord.— The  spermatic  cord  consists  of  (1)  the  vas 
deferens,  (2)  the  artery  of  the  vas  deferens,  (3)  the  spermatic  artery, 


THE  MALE  URETHRA  AND  EXTERNAL  GENITALS  473 


(4)  sympathetic  nerves  accompanying  the  arteries,  (5)  the  veins  ac- 
companying the  two  arteries,  (6)  lymphatics  running  with  the  veins, 
7i  the  remains  of  the  processus  vaginalis,  sometimes  present,  and  (8) 
the  internal  cremaster  fibers  of  Henle.  All  these  structures  are  joined 
together  by  a  fatty,  connective  tissue,  continuous  with  the  subperitoneal 
tissue,  which  may  give  origin  to  inguinal  or  scrotal  lipoma,  simulating 
true  herniae. 

The  vas  deferens  lies  to  the  inner  side  and  behind  the  epididymis  at 
the  commencement  of  the  cord,  and  bears  the  same  relative  position  to 
the  other  elements  of  the  cord  above,  where  its  hard,  cord-like  feeling 

Fig.  162 

vas  deferens 

AND   ITS 
ARTERY 


GLOBUS    MAJOR 
OF    EPIDIDYMIS 


DIGITAL   FOSSA 


SPERMATIC 
ARTERY 


PAMPINIFORM 
PLEXUS 


VAS    DEFERENS 


GLOBUS  MINOR 
OF    EPIDIDYMIS 


Left  teetU  with  spermatic  cord.     Lateral  view.     (Joeasel.) 

enables  it  to  be  readily  found  or  avoided  as  occasion  requires  (seep.  430). 
In  castration  for  tuberculosis  or  tumor  of  the  testis,  vie,  especially  if 

the  cord  is  involved,  it  is  often  advisable  to  remove  it  as  high  up  as 
pot  lible.  Thi^  may  be  done  by  incising  as  far  as  the  internal  abdominal 
ring   down    to    the    peritoneum    mid    stripping   it    from    the    underlying 

The  two  arteries  and  their  accompanying  veins  require  ligation, 
and  it  is  well  to  ligate  them  separately  rather  than  to  ligate  the  cord 
en  in. i 

11m-  cord  is  covered  by  the  same  layers  thai  envelop  the  testis,  except 
the  tunica  vaginalis.  Superiorly  the  dartos  is  replaced  by  superficial 
fa  da,  between  which  and  the  skin  is  a  layer  of  subcutaneous  fat.      In 


474  PELVIS  AND  PERINEUM 

reaching  the  cord,  as  in  operations  for  varicocele,  branches  of  the  external 
pudic,  cremasteric  and  superficial  epigastric  arteries  are  likely  to  be 
divided,  and  perhaps  some  branches  of  the  superficial  perineal  arteries. 

The  veins  of  the  spermatic  or  pampiniform  plexus,  to  the  number  of 
five  or  six,  lie  in  front  of  and  surround  the  spermatic  artery  and  present 
frequent  anastomoses.  They  coalesce  to  three  or  four  plexiform  trunks 
in  the  inguinal  canal,  which  unite  into  two  or  three  and  finally  near  their 
termination  into  a  single  vein  accompanying  the  spermatic  artery  in 
the  abdomen.  The  frequency  of  varicosities  of  the  spermatic  veins, 
or  varicocele,  is  explained  by  their  length,  dependent  position,  few  and 
imperfect  valves,  lack  of  external  support  from  the  loose  surrounding 
tissue,  pressure  in  their  passage  through  the  inguinal  canal,  and  their 
large  size  as  compared  with  the  arteries,  which  renders  the  blood  current 
sluggish.  The  aid  furnished  to  many  veins  by  muscular  contraction 
is  also  wanting.  Those  with  a  normally  active  dartos  seldom  have 
varicocele.  Several  facts  may  be  given  to  explain  the  greater  frequency 
(90  per  cent.)  of  varicocele  on  the  left  side,  i.  e.,  the  greater  length  of  the 
left  spermatic  cord,  the  pressure  of  the  sigmoid  colon,  especially  in  cases 
of  constipation,  on  the  left  spermatic  vein,  and  the  passage  of  the  latter 
at  a  right  angle  into  the  renal  vein,  while  the  right  vein  enters  the  cava 
at  an  acute  angle.  Congenital  defects  of  development  may  also  help 
to  explain  the  above  features  of  varicocele,  but  this  explanation  is  a 
supposition  and  needs  explanation  itself.  Varicocele  is  especially  an 
affection  of  early  adult  life,  and  often  spontaneously  diminishes  with  the 
diminution  of  sexual  vigor  in  old  age.  Of  the  two  sets  of  veins  it  is  the 
anterior  set,  or  the  spermatic  plexus  accompanying  the  spermatic  artery, 
which  is  principally  or  solely  involved. 

In  ligation  or  excision  of  these  veins  we  must  avoid  the  smaller  set 
accompanying  the  vas  deferens,  which  are  sufficient  to  carry  on  the 
venous  circulation.  The  spermatic  artery  need  not  be  spared  from  among 
the  veins,  even  if  it  can  be,  for  the  anastomoses  with  the  artery  of  the 
vas  deferens  and  the  scrotal  arteries  are  sufficient  to  supply  the  testis. 
It  is  important,  however,  to  spare  the  genitocrural  nerve,  which  supplies 
the  cremaster  muscle,  for  otherwise  this  muscle  would  be  paralyzed  and 
the  testis  would  hang  lower  than  before.  At  the  internal  abdominal 
ring  the  cord  is  formed  by  the  coming  together  of  the  vas  deferens  and 
its  vessels  with  the  spermatic  vessels. 


THE  PERINEUM. 

This  corresponds  to  the  outlet  of  the  pelvis  and  includes  the  structures 
between  the  skin  below  and  the  pelvic  floor  above. 

Boundaries  and  Surface  Landmarks. — Its  bony  and  fibrous  boun- 
daries form  a  lozenge-shaped  figure  with  the  symphysis  in  front,  the 
coccyx  behind,  and  the  ischiopubic  rami,  the  ischial  tuberosities,  and 
the  great  sacrosciatic  ligaments  on  the  sides.  By  deep  pressure  we 
can  feel  the  bony  landmarks,  and  in  thin  subjects  the  sciatic  ligaments, 


THE  PERINEUM  475 

beneath  the  inner  margins  of  the  glutei  maximi.  In  the  erect  position 
the  sciatic  ligaments  are  overlapped  by  the  internal  borders  of  these 
muscles,  but  not  in  the  sitting  or  lithotomy  position.  The  bony  boun- 
daries are  seen  to  correspond  with  the  pelvic  outlet,  and  hence  vary  in 
size  in  the  two  sexes  (see  p.  401).  In  the  male  the  transverse  diameter 
between  the  ischial  tuberosities,  usually  9  cm.  (3^  in.),  is  sometimes 
so  narrow,  5  cm.  (2  in.),  as  to  interfere  with  lateral  perineal  incisions. 
The  average  anteroposterior  diameter  in  the  male  is  9  cm.  (3^  in.), 
but  owing  to  the  convexity  of  the  parts  the  surface  measures  10  cm. 
(4  in.). 

Superficially,  the  male  perineum  is  limited  by  the  scrotum  in  front, 
the  buttocks  behind,  and  the  thighs  laterally.  With  the  thighs  together 
and  extended  the  perineum  appears  as  a  furrow  between  them,  but 
with  the  thighs  flexed  and  abducted  (lithotomy  position)  the  perineum 
appears  as  bounded  above.  The  median  raphe  of  the  skin  extends 
forward  from  the  anus  to  the  scrotum  and  thence  onto  the  penis.  As 
it  represents  the  embryonic  cutaneous  seam  of  the  two  halves  of  the 
perineum,  no  large  vessels  cross  it,  hence  it  is  chosen  for  incisions  when 
possible.  It  is  well  to  remember  that  it  may  be  displaced  to  one  side 
by  adhesions.  The  centre  of  the  anus  lies  in  a  line  connecting  the  tips 
of  the  ischial  tuberosities  and  about  4  cm.  (1^  in.)  from  the  tip  of  the 

coccyx. 

The  depth  of  the  perineum,  or  the  distance  between  the  surface  and 
the  pelvic  floor,  varies  individually  with  the  amount  of  subcutaneous 
fat,  and  locally  in  the  different  parts  of  the  area.  Thus  in  the  pos- 
terior and  lateral  parts  it  measures  5  to  7.5  cm.  (2  to  3  in.),  but  less 
than  2.5  cm.  (1  in.)  anteriorly.  It  is  important  to  bear  in  mind  this 
distance  in  operating  on  the  pelvic  viscera  through  the  perineum,  as  in 
opening  the  bladder,  etc.  The  central  tendinous  point  of  the  perineum 
lies  in  the  median  line,  midway  between  the  centre  of  the  anus  and  the 
perineoscrotal  junction  and  2.5  cm.  (1  in.)  in  front  of  the  anus.  It  is 
the  meeting  point  of  the  bulbocavernous,  superficial  transversus  perinei, 
sphincter  ani  and  a  few  fibers  of  the  levator  ani  muscles,  and  the  super- 
ficial and  deep  perineal  fasciae.  As  it  corresponds  to  the  centre  of  the 
posterior  edge  of  the  deep  perineal  fascia  (triangular  ligament)  the  bulb 
and  its  artery  are  just  in  front  of  it.  Hence  in  lithotomy  and  similar 
operations  the  incision  should  not  commence  much  in  front  of  this  point. 
(  orresponding  to  the  bulb  and  the  perineal  portion  of  the  corpus  spongi- 
osum, the  surface  is  somewhat  elevated  in  the  median  line  in  front  of  the 
centra]  point,  and  this  elevation  may  serve  as  a  guide  to  the  position 
of  the  bulb. 

At:  i    line  inclined  somewhat  forward  from  the  anterior  pari 

of  each  ischial  tuberosity,  passing  through  the  "central  point,"  divides 
tin-  region  into  an  anterior  or  urethral  triangle  (perineum  proper)  and 
;i  posterior  or  anal  triangle. 

The  "Perineum  Proper."  The  "perineum  proper"  has  the  form 
of  .hi  equilateral  triangle,  measuring  about  8  cm.  (-U  in.)  on  all  sides. 
The  base  i     nol  <|uii<-  Straight,  but  inclines  forward  from  either  side  to 


476 


PELVIS  AND  PERINEUM 


the  middle  line,  at  the  central  point  of  the  perineum.  The  skin  is  freely 
movable  on  the  subjacent  parts,  and  is  dark  and  thin,  readily  showing 
any  extravasation  of  blood  beneath  it.  The  superficial  layer  of  the 
superficial  fascia  contains  little  or  no  fat  in  the  middle  line,  but  more  fat 
laterally  and  posteriorly,  where  it  is  continuous  with  the  subcutaneous 
fat  of  the  thighs,  of  the  ischiorectal  fossse,  and  of  the  buttocks.  The 
superficial  lymphatics  run  into  the  superior  inguinal  nodes. 

Apart  from  the  preceding  layers,  the  perineum  proper  consists  of  a 
triangular  ledge  of  tissue,  composed  of  three  strong  layers  of  fascia  stretch- 
ing nearly  horizontally  between  the  ischiopubic  rami  and  enclosing  two 
interfascial  spaces.  It  is  pierced  by  the  urethra  and,  in  the  female,  by 
the  vagina. 

Fig.  163 


Muscles  of  the  male  perineum.      (Gerrish,  after  Testut.) 

The  deep  or  membranous  layer  of  the  superficial  fascia,  the  fascia  of 
Colles  or  "perineal  fascia,"  turns  up  behind  the  superficial  transversus 
perinei  muscle  to  join  the  base  of  the  triangular  ligament,  and  thus  helps 
to  form  the  free  posterior  border  of  the  "perineal  ledge."  It  thus  shuts 
off  a  subfascial  space  (the  superficial  perineal  interspace)  from  the 
ischiorectal  fossa  behind  it.  This  space  is  separated  from  the  thighs 
on  either  side  by  the  attachment  of  the  fascia  to  the  ischiopubic  rami, 
and  from  the  pelvis  by  the  attachment  of  the  triangular  ligament  to 
the  same  parts.  Hence  there  is  only  one  outlet  for  urine  extravasated 
into  this  space,  from  rupture  of  the  urethra  contained  within  it,  and 
that  is  forward  to  the  scrotum  and  penis  and  thence,  between  the  two 
pubic  spines,  onto  the  abdomen  beneath  the  deep  layer  of  the  super- 


THE  PERINEUM  477 

ficial  fascia,  with  which  this  perineal  fascia  is  continuous  (see  p.  270). 
Extravasation  of  urine  from  rupture  of  the  urethra  is  especially  liable  to 
occur  in  this  space,  beneath  the  perineal  fascia,  for  it  contains  the  bul- 
bous urethra.  The  products  of  inflammation  and  other  fluid  collections 
take  the  same  course. 

From  the  perineal  fascia  to  the  pelvic  floor  we  find  alternate  layers 
of  fascia  and  muscle,  etc.  Thus  in  the  subfascial  space,  beneath  the 
perineal  fascia  and  superficial  to  the  triangular  ligament,  we  find  the 
root  of  the  penis  and  its  muscles,  vessels,  and  nerves,  together  with 
the  superficial  transversus  perinei  muscles  and  their  vessels  and  nerves. 
The  latter  muscles,  lying  along  the  posterior  boundary  or  base  of  this 
region,  together  with  their  accompanying  vessels  and  nerves,  serve  as 
landmarks,  and  are  liable  to  be  cut  into  or  across  in  lateral  incisions, 
as  -in  lateral  lithotomy.  They  may  be  cut  with  impunity.  Forming 
the  root  of  the  penis  we  find  laterally  the  crura  penis  covered  by  the 
ischiocavernosi  muscles  and  attached  to  the  ischiopubic  rami,  and 
mesially  the  bulb  covered  by  the  bulbocavernosus.  The  space  is 
divided  by  the  bulbocavernosus  into  two  lateral  muscular  triangles, 
bounded  laterally  by  the  erectores  penis,  covering  the  crura  penis,  and 
posteriorly  by  the  two  superficial  transversus  perinei  muscles.  Some- 
times these  muscles  cover,  or  nearly  cover,  the  entire  area,  and  again 
they  may  leave  a  considerable  gap  between  them,  showing  the  next 
deeper  layer,  the  triangular  ligament,  which  forms  the  roof  (often  called 
the  floor)  of  this  space. 

The  triangular  ligament  measures  about  3.7  cm.  (l£  in.)  from  the  sub- 
pubic ligament  to  the  middle  of  its  base,  at  the  central  point  of  the 
perineum.  Its  principal  function  is  to  support  the  urethra  in  its  course 
beneath  the  symphysis.  Along  its  base  its  two  layers  fuse  with  one 
another  and  with  the  perineal  fascia,  and  thereby  inclose  the  perineal 
interspaces  posteriorly  and  form  the  free  border  of  the  perineal  ledge. 
This  border  is  incised  in  lateral  and  median  lithotomy  and  in  the  perineal 
operations  on  the  urethra,  bladder,  prostate,  etc.  The  two  layers  of 
the  triangular  ligament  separate  from  one  another  anteriorly  to  inclose 
the  wedge-shaped  deep  perineal  interspace. 

The  superficial  layer  of  the  triangular  ligament  is  pierced  by  the  urethra 
about  2..")  cm.  I  I  in.  |  behind  the  symphysis,  and  behind  and  at  the  sides 
of  this  opening  are  closely  attached  the  bulb  of  the  urethra  and  its  sheath, 
while  the  tir/eri/  of  the  hull)  pierces  it  on  either  side  of  the  urethral  open- 
ing. It  is  also  pierced  by  the  ducts  of  Cowper's  glands  on  each  side  of 
and  somewhat  behind  the  urethral  aperture,  and  by  the  vessels  of  the 
corpora  cavernosa  more  anteriorly  and  close  to  the  lateral  attachment  of 

the  ligament.  Anteriorly  "  small  gap  is  left  between  this  layer  and  the 
lubpubic  ligament,  through  which  the  dorsal  vessels  and  nerves  of  the 
penis  pas  from  the  deep  to  the  superficial  perineal  interspace.  The 
anterior  part  of  this  layer,  forming  the  posterior  boundary  of  the  aper- 
ture for  the  dorsal  vessels,  etc.,  is  somewhat  thickened  and  is  sonic- 
time,  called  the  pre-urethral  ligament  (Joessel,  Waldeyer).  Later- 
ally this  layer  i  firmly  attached  to  the  ischiopubic  rami,  above  (lie 
attachment  of  the  perineal  fascia. 


478 


PELVIS  AND  PERINEUM 


The  deep  perineal  interspace,  between  the  two  layers  of  the  trian- 
gular ligament,  is  wedge-shaped,  with  the  apex  behind,  where  the  two 
layers  come  together.  It  contains  the  membranous  urethra  (see  p. 
454),  Cowper's  glands  (see  p.  454),  the  deep  transversus  perinei  or 
compressor  urethrse  muscle,  the  internal  pudic  vessels,  nerves,  and 
lymphatics  with  their  terminal  and  deep  branches  (i.  e.,  to  the  bulb,  the 
corpora  cavernosa,  and  the  dorsum  of  the  penis).  The  deep  transversus 
perinei  or  compressor  urethrse  muscle  is  a  voluntary  muscle  whose  inner 
circular  fibers  surround  the  membranous  urethra  and  are  continuous 
with  the  external  sphincter  vesicae  at  the  lower  end  of  the  prostatic 


Fig.  164 


DEEP    LAYER    OF 
SUPERFICIAL 
FASCIA 


AREA    OF  CONTACT 

WITH    BULB,    RIGHT 

SIDE 

SUPERFICIAL    LAYER 

OF    TRIANGULAR 

LIGAMENT 


SYMPHYSIS 


deep  transverse 
perinei  muscle 

cowper's  gland 
(within  muscle) 


VAS    DEFERENS   AND 
SEMINAL    VESICLES 


Deep  layer  of  muscles  of  the  male  perineum.  On  the  left  side  of  the  subject  the  superficial 
layer  of  the  triangular  ligament  has  been  removed,  on  the  right  side  it  is  in  place  over  the  com- 
pressor urethrae  or  deep  transversus  perinei  muscle.  The  central  part  of  the  levator  ani  is 
removed,  exposing  the  prostate,  etc.      (Testut.) 


urethra.  The  greater  part  of  its  fibers  pass  transversely  and  join  an 
indistinct  median  raphe,  while  a  few  run  obliquely  and  sagittally.  They 
compress  and  help  to  expel  the  contents  of  the  membranous  urethra  and 
of  Cowper's  glands,  as  in  emission,  they  assist  the  external  sphincter 
vesicae,  and  aid  the  erection  of  the  penis  by  compression  of  the  veins  from 
the  bulb,  the  corpora  cavernosa,  and  the  dorsum  of  the  penis,  which 
pass  through  it.  Some  of  its  fibers  are  cut  in  lateral  lithotomy,  and,  to 
a  less  extent,  in  many  median  perineal  operations. 

The  artery  of  the  bulb  runs  inward  in  this  interspace  about  12  mm. 
(i  in.),  sometimes  less,  in  front  of  the  base  of  the  ligament,  or  3  to  3.7  cm. 


THE  PERINEUM  479 

(1?  to  lh  in.)  in  front  of  the  anus.  Hence  the  incision  in  lateral  lith- 
otomy, etc.,  should  not  be  commenced  more  than  3  cm.  (1^  in.)  in  front 
of  the  anus,  to  avoid  wounding  this  artery. 

The  superior  or  deep  layer  of  the  triangular  ligament  is  continuous 
with  the  obturator  fascia  along  the  upper  lip  of  the  inner  edge  of  the 
ischiopubic  rami,  where  both  these  fasciae  are  attached.  It  joins  the 
superficial  layer  anteriorly,  at  the  pre-urethral  ligament,  and  posteriorly 
along  the  posterior  edge  of  the  perineal  ledge.  Superiorly  it  forms 
the  floor  of  the  anterior  recess  of  the  ischiorectal  fossa,  on  either  side 
of  the  prostate.  The  apex  of  the  prostate  rests  upon  it  mesially,  and 
its  fibrous  capsule,  derived  from  the  rectovesical  fascia,  fuses  with  it. 
The  dorsal  vein  passes  between  it  and  the  subpubic  ligament,  the  pudic 
vessels  and  nerves  pierce  it.  Incision  through  the  posterior  part  of 
this  layer  on  either  side  opens  the  anterior  recess  of  the  ischiorectal 
fossa,  and  then,  being  continued  more  deeply,  cuts  the  levator  ani 
with  the  anal  fascia  below  and  the  rectovesical  fascia  above  it,  and  thus 
enters  the  pelvic  cavity.  Median  incision  through  this  layer  involves 
the  prostate  above  it. 

In  lateral  lithotomy  the  5  to  7.5  cm.  (2  to  3  in.)  long  incision,  commenced 
about  3  cm.  (l\  in.)  in  front  of  the  anus  and  a  little  to  the  left  of  the 
median  line  (to  avoid  the  bulb  and  its  artery),  is  carried  backward  and 
outward  to  a  point  somewhat  behind  and  external  to  the  midpoint 
between  the  anus  and  the  ischial  tuberosity.  Through  the  anterior 
and  deeper  part  of  the  incision  the  knife  is  carried  into  the  membranous 
urethra  and,  along  the  staff,  through  this  and  the  prostate  into  the  bladder. 
The  prostate  is  divided  obliquely  backward  and  outward.  We  divide 
the  skin,  the  superficial  fasciae,  the  transversus  perinei  muscle,  vessels, 
and  nerve,  the  inferior  hemorrhoidal  vessels  and  nerves,  the  base  of 
the  triangular  ligament  and  compressor  urethrse  muscle,  the  membran- 
ous and  prostatic  urethral,  the  anterior  fibers  of  the  levator  ani,  and  the 
left  lateral  lobe  of  the  prostate. 

Parts  to  be  Avoided. — We  avoid  wounding  the  bulb  by  commencing 
the  incision  to  one  side  of  the  median  line  and  by  drawing  the  staff, 
and  with  it  the  bulb,  well  forward  under  the  pubes.  The  artery  of  the 
bulb  is  avoided  by  commencing  the  incision  not  more  than  3  cm. 
(1J  in.)  in  front  of  the  anus.  The  rectum  is  easily  avoidable  if  it  is  not 
distended  and  if  the  posterior  part  of  the  incision  is  not  carried  too  far 
back  or  too  near  the  median  line.  On  the  other  hand,  the  pudic  vessels 
may  possibly,  though  not  probably,  be  wounded  if  the  incision  is  carried 
far  to  the  side.  If  the  incision  in  the  prostate  passes  beyond  the  prostatic 
capsule,  jo  a  to  incise  the  rectovesical  fascia, it  lays  open  the  subperitoneal 
le  of  the  pelvic  cavity,  the  ischiorectal  fossa,  and  the  neck  of  the 
bladder  into  one  large  space.  This  is  most  likely  to  occur  in  incising 
the  vesical  outlet,  for  the  incision  into  the  lower  end  of  the  gland  is 
below  the  reflection  of  the  rectovesical  fascia  from  the  pelvic  floor  onto 
the  prostate.  If  the  prostatic  incision  is  too  vertical,  the  lef t  ejaculatory 
duct  Ls  in  danger  of  being  incised.     The  lower  pari  of  the  prostatic 


480 


PELVIS  AND  PERINEUM 


venous^  plexus  cannot  escape.  When  the  accessory  pudic  artery  is  pres- 
ent, it  is  likely  to  be  injured,  as  it  passes  forward  along  the  side  of  the 
prostate.  In  children  lateral  lithotomy  or  any  form  of  perineal  approach 
to  the  bladder  is  more  difficult  and  objectionable,  because  the  pelvis 
pelvic  outlet,  and  perineum  are  narrow;  the  bladder  is  higher  up,  more 
movable,  and  less  strongly  attached,  and  the  prostate  is  rudimentary,  so 


Fig.  165 


RAPHI  OFBULBOCAV- 
ERNOSUS   MUSCLE 


DEEP   PERINEAL. 
FASCIA 


CENTRAL   POINT  OF 
PERINEUM 


BULBOCAVERNOSUS 
MUSCLE 

ISCHIOCAVERNOSUS 
MUSCLE 

TRIANGULAR  LIGA- 
MENT, SUPERFICIAL 
LAYER 

SUPERFICIALTRANS- 
VERSUS    PERINEI 
MUSCLE 

RECTO- URETHRA  LIS 
MUSCLE 

SPHINCTER  ANI 
MUSCLE 


EXT.  SPHINCTER  ANI 
—  MUSCLE, TURNED  BACK 


Male  perineum. 

that  more  of  the  vesical  outlet  itself  has  to  be  cut,  while  the  peritoneal 
pouch  descends  lower  and  may  be  wounded.    The  suprapubic  route,  on 
the  other  hand,  is  easier  on  account  of  the  high  position  of  the  bladder 
so  that  it  is  to  be  preferred. 

In  median  lithotomy  or  cystotomy,  or  the  similar  incision  in  external 
urethrotomy,  perineal  section,  etc,  the  parts  divided  are  (1)  the  skin  in 


THE  PERINEUM  481 

the  median  raphe"  in  front  of  the  anus  for  3  cm.  (1\  in.),  (2)  superficial 
fascia,  (3)  sphincter  ani,  (4)  the  central  point  of  the  perineum,  (5)  the 
base  of  the  triangular  ligament  and  of  (6)  the  compressor  urethrse  muscle, 
and  (7)  the  membranous  urethra.  One  finger  in  the  rectum  to  guide 
the  upwardly  directed  knife  diminishes  the  risk  of  wounding  the  gut. 
There  is  less  cutting  and  more  dilating  in  median  cystotomy,  for  the  pros- 
tatic urethra  and  vesical  outlet  are  only  dilated  and  not  cut.  The  advan- 
tages of  the  median  operation  consist  in  (1)  the  little  bleeding,  owing 
to  the  slight  vascularity  of  the  raphe  and  median  line  of  the  perineum, 
and  (2)  the  little  danger  of  wounding  the  ejaculatory  ducts  or  the  pelvic 
fascia,  for  the  prostate  and  vesical  outlet  are  stretched  and  not  cut.  It 
is  an  excellent  operation  for  the  extraction  of  small  stones.  On  the 
other  hand,  it  possesses  disadvantages  in  (1)  the  danger  of  wounding  the 
bulb,  which,  however,  does  not  bleed  much  if  incised  in  the  exact  median 
line,  and  (2)  the  little  space  obtained  for  the  extraction  of  a  stone.  More- 
over, in  children  it  is  contra-indicated,  for,  owing  to  the  small  size  of  the 
prostate  and  vesical  outlet  and  the  slight  attachments  of  these  parts,  the 
bladder  may  be  torn  from  the  urethra  in  attempting  to  reach  its  cavity 
with  the  finger. 

When  we  wish  to  expose  the  prostate  or  seminal  vesicles,  other  perineal 
incisions  are  useful,  such  as  the  anterior  curved  transverse  incision  of 
Zuckerkandl,  the  inverted  V  or  Y  incision  of  Young,  and  the  median 
incision  encircling  the  anus  on  one  side,  as  in  v.  Dittel's  lateral  prosta- 
tectomy. Zuckerkandl's  incision  is  concave  toward  the  rectum.  The 
greater  part  of  these  incisions  is  in  the  ischiorectal  region.  They  aim  to 
expose  the  prostate  after  dividing  the  anterior  fibers  of  the  levator  ani 
muscle.  The  seminal  vesicles  may  then  be  exposed  by  separating  the 
rectum  from  the  prostate  and  bladder.  In  these  incisions  we  expose 
the  recto-urethralis  muscle  (see  Fig.  165),  a  short  muscle  with  rather 
indefinite  margins,  which  joins  the  rectum  and  the  membranous  urethra 
in  the  median  line.  To  expose  the  membranous  urethra  and  the  apex 
of  the  prostate  by  a  transverse  incision  this  muscle  must  be  divided. 
Its  division  allows  the  rectum  to  drop  back  and  the  prostate  to  be  sepa- 
rated from  it.  If  not  divided,  the  rectum  is  liable  to  be  torn.  It  is  made 
prominent  by  retracting  the  central  point  of  the  perineum  forward.  In 
all  perineal  operations  on  the  male  bladder  it  should  be  remembered 
that  the  vesical  outlet  lies  6.5  to  7.5  cm.  (2^  to  3  in.)  from  the  surface, 
in  the  lithotomy  position.  But  this  distance  may  be  so  increased  in 
some  cases  of  prostatic  hypertrophy  as  to  make  the  perineal  route  to 
the  bladder  difficult  or  even  contra-indicated. 

The  Perineum  in  the  Female. — The  perineum  in  the  female  differs 
from  that  in  the  male  in  the  perforation  of  all  the  layers  in  the  median 
line  by  the  vulvovaginal  passage  and  the  resulting  necessary  adaptation 
of  the  muscles.  It  is  as  if  the  bulbocavernosi  and  the  bulb  were  cleft  in 
two  halves  through  their  median  raphe*.  The  median  cleft  thus  formed 
represents  the  vulva  and  the  lower  end  of  the  vagina,  while  the  two 
halves  of  the  bulb  and  of  the  bulbocavernosi  represent  the  bulbi  ves- 
tibuli  and  the  attenuated  compressor  or  sphincter  vaginae  respectively. 


482 


PELVIS  AND  PERINEUM 


The  corpora  cavernosa,  the  ischiocavernosi,  and  the  superficial  transverse 
perinei  muscles  differ  only  in  their  smaller  size.  The  deep  transversus 
perinei  muscle,  like  the  two  layers  of  the  triangular  ligament  is  of  course 
partly  cleft  by  the  vagina. 

The  "perineal  body,"  triangular  on  sagittal  section  and  bounded  in 
front  by  the  vulvovaginal  wall,  behind  by  the  anterior  rectal  wall,  and 
below  by  the  cutaneous  surface  between  the  anus  and  the  posterior 
vulvar  commissure,  is  peculiar  to  the  female.     Besides  the  central  point 


Fig.  166 


OBTURATOR 
OR  PELVIC 
FASCIA 


RECTOVESI- 
CAL   FASCIA 
ANAL  FASCIA 
OBTURATOR 
FASCIA 
INT.    PUDIC 
ARTERY 
INF.   HEMOR- 
RHOIDAL ART 


PERITO- 
NEUM 


Frontal  section  of  the  ischiorectal  space,  passing  through  the  ischial  tuberosities.      (Tillaux.) 

of  the  perineum  and  the  muscles  that  meet  here,  it  contains  a  meshwork 
of  connective  tissue  and  elastic  fibers,  and  unstriped  muscle  tissue. 
Thus  it  is  fitted  to  stretch  in  parturition,  as  it  does  to  a  remarkable 
degree  during  the  passage  of  the  head.  It  is  in  this  part  and  the  pos- 
terior vulvovaginal  wall  that  ruptures  of  the  perineum  occur  during 
labor.  Such  ruptures  may  be  superficial  or  they  may  even  extend 
entirely  through  into  the  rectum.  It  is  the  ischiorectal  regions  and  the 
portion  of  the  perineum  behind  the  vulva,  not  the  firmer  anterior  part, 
that  yield  most  in  parturition,  so  as  to  allow  the  passage  of  the  fetal 


THE  PERINEUM  483 

head.  The  cutaneous  base  of  the  perineal  body,  between  the  anal 
and  vaginal  orifices,  is  often  spoken  of  as  the  "perineum."  It  measures 
.'•>  cm.  (ly  in.)  anteroposteriorly  and  extends  laterally  between  the  two 
ischial  tuberosities. 

The  Anal  Triangle  or  Ischiorectal  Region. — The  superficial  fascia 
contains  a  great  abundance  of  fat  which  fills  the  two  pyramidal  ischio- 
rectal fossae,  lying  one  on  either  side  of  the  anus  (Fig.  166).  These 
fossa?  are  bounded  above  and  internally  by  the  obliquely  directed  levator 
ani  and  coccygeus  muscles  (pelvic  floor),  lined  beneath  by  the  ischio- 
rectal or  anal  fascia,  and  externally  by  the  vertical  obturator  internus, 
covered  by  the  obturator  fascia.  In  front  each  fossa  ends  superficially 
at  the  base  of  the  perineal  ledge,  but  more  deeply  it  extends  forward, 
nearly  as  far  as  the  symphysis,  as  the  anterior  recess.  This  lies  on  top 
of  the  perineal  ledge,  beneath  the  levator  ani,  and  extends  forward  on 
either  side  of  the  prostate,  between  it  and  the  ischiopubic  rami  laterally. 
Posteriorly  each  fossa  ends  superficially  along  the  great  sacrosciatic 
ligament,  but  deeply  it  extends  backward  a  variable  distance  toward 
the  sacrum  between  the  ligament  and  the  pelvic  floor,  as  the  posterior 
recess. 

The  apex  of  the  fossa  is  along  the  white  line  on  the  obturator  fascia, 
or  a  little  below  it,  so  that  its  depth  is  about  5  cm.  (2  in.)  behind,  less  in 
front.  The  base  measures  2.5  cm.  (1  in.)  in  breadth  and  5 cm.  (2  in.)  from 
before  backward.  Crossing  this  space  about  its  centre,  from  the  lateral 
wall  to  the  anus,  are  the  inferior  hemorrhoidal  vessels,  while  the  external 
angle  is  crossed  by  the  superficial  perineal  vessels  and  nerves  and  along 
the  posterior  border  runs  the  fourth  sacral  nerve.  The  presence  of  these 
mrves,  especially  the  hemorrhoidal,  explains  the  great  pain  which  usually 
accompanies  ischiorectal  abscess.  In  opening  an  ischiorectal  abscess 
the  structures  to  avoid  are  the  pudic  and  inferior  hemorrhoidal  vessels 
and  the  rectum.  We  incise  in  a  line  radiating  from  the  anus,  being  care- 
ful not  to  incise  too  deeply  near  the  anus,  on  account  of  the  rectum,  or 
too  far  toward  the  tuber  ischii,  where  the  pudic  vessels  run  in  a  canal 
Alcock's)  in  the  obturator  fascia,  2.5  to  3.7  cm.  (1  to  1^  in.)  above  the 
lower  end  of  the  tuberosity.  Early  incision  should  be  practised  to  pre- 
vent the  inflammation  from  extending  throughout  the  entire  fossa. 

Inflammation  in  the  ischiorectal  fossa  is  favored  by  the  poor  blood 
supply  of  the  contained  fat  and  by  the  tendency  to  congestion,  due  to 
the  dependent  position  and  the  lack  of  support  of  the  veins,  especially  in 
patients  suffering  from  venous  congestion  or  feeble  circulation,  such  as 
occurs  in  diseases  of  the  liver  (cirrhosis),  heart,  and  lungs  (phthisis). 
The  inflammation  is  also  favored  by  sitting  on  a  cold,  wet  seat,  by  injury, 
and  by  the  pa  age  of  infection  through  the  rectal  wall,  preceded  per- 
haps by  an  ulcer  of  the  lower  rectum.  Ischiorectal  abscess  bulges  and 
tends  to  break  where  resistance  is  least,  i.  e.,  in  the  rectum,  or  on  the 
skin  beside  the  anus  or  along  the  border  of  the  gluteus  maximus.  If  it 
perforates  both  on  the  4.  in  and  in  the  rectum,  :i  complete  fistula  in  ano 
!t  whose  internal  opening  is  usually  within  12  nun.  (\  in.)  of  the 
anu  .    Owing  to  the  constant  dragging  aparl  of  the  walls,  toward  the 


484 


PELVIS  AND  PERINEUM 


anus  by  the  sphincter  and  from  the  anus  by  the  levator  ani,  and  the 
re-infection  of  the  tract  from  the  rectum,  spontaneous  cure  is  rare  and 
operation  is  required  (see  also  p.  416). 

The  pad  of  fat  filling  the  ischiorectal  fossa  serves  as  an  elastic  cushion 
to  the  rectum  and  allows  its  descent  and  expansion  during  defecation. 
The  anal  portion  of  the  rectum  occupies  the  space  between  these  two 
fossae.  The  ischiorectal  fossa  is  opened  into  in  lateral  lithotomy  and 
in  the  lateral  and  the  transversely  curved  incisions  to  expose  the  pros- 
tate, seminal  vesicles,  etc. 


CHAPTER    VI. 

tTHE   LOWER   EXTREMITY. 

The  lower  extremity  is  especially  adapted  to  bear  the  weight  of  the 
body  by  its  stronger  and  heavier  build  and  the  stronger  and  less  movable 
connection  of  its  first  segment,  the  thigh,  as  compared  with  the  upper 
extremity. 

THE  HIP. 

The  upper  segment,  the  region  of  the  hip,  will  be  studied  in  two 
sections:  (1)  a  posterior  or  gluteal  region,  the  buttocks,  and  (2)  aD 
anterior  region,  including  the  hip  joint. 

The  Posterior  or  Gluteal  Region,  the  Buttocks. 

This  region  is  bounded  above  by  the  iliac  crest,  below  by  the  gluteal 
fold,  internally  by  the  sacrum  and  coccyx,  and  externally  by  a  line 
From  the  anterior  superior  iliac  spine  to  the  great  trochanter. 

Surface  Markings  and  Landmarks. — The  iliac  crest  and  its  an- 
terior superior  spine  are  readily  felt.  The  posterior  superior  spine  is  less 
distinct,  especially  in  stout  subjects,  in  whom  its  position  is  indicated 
by  a  small  depression.  The  great  trochanter  is  a  prominent  landmark, 
especially  when  the  thigh  is  adducted  or  rotated  out.  In  very  stout 
subjects  a  slight  depression  marks  its  position.  Its  upper  border  is 
made  less  sharply  defined  by  the  tendon  of  the  gluteus  medius  which 
passes  over  it.  Tlie  ischial  tuberosities  are  readily  felt  on  the  border- 
line between  the  buttocks  and  the  perineum.  When  the  thighs  are  ex- 
tended  they  are  covered  by  the  fleshy  fibers  of  the  lower  borders  of  the 
glutei  tnaximi,  which  rise  above  them  when  the  thighs  are  flexed.  The 
•  tic  natch  can  only  be  felt  in  those  greatly  emaciated.  The  transverse 
gluteal  fold,  or  "fold  of  the  buttocks,"  is  neither  due  to  nor  does  it  cor- 
respond with  the  lower  border  of  the  gluteus  inaximus,  which  is  lower 
and  more  oblique  than  the  fold.  The  fold  is  due  to  a  creasing  of  the 
-.kin  in  extension  of  the  hip.    Inflexion  of  the  hip  joint  the  buttocks 

are  flattened  and   the  fold  becomes  Oblique  and   is  finally  obliterated.     Its 

disappearance  and  the  flattening  of  file  bullocks  in  early  hip  disease 
are  u  eful  diagnostic  ign  ,  and  are  due  to  (lie  flexion  of  the  hip  joint, 
which  is  almost  constantly  present.  They  are  not  due  to  but  precede 
the  wasting  <>\'  die  gluteal  muscles,  which  exaggerates  these  symptoms. 
The  (jrrdi  iocroeeiaHc  ligament  can  be  felt  <>n  deep  pressure  beneath  the 


4S6  THE  LOWER  EXTREMITY 

lower  edge  of  the  gluteus  maximus.  The  tensor  fasciae  latce  (vaginae 
femoris)  forms  a  slight  prominence  extending  from  a  point  just  outside 
the  anterior  superior  spine  downward  and  somewhat  backward  to  the 
ilio tibial  band,  on  the  outer  aspect  of  the  thigh,  7.5  to  10  cm.  (3  to  4  in.) 
below  the  great  trochanter. 

Topography. — The  posterior  superior  iliac  spine  is  on  a  level  with 
the  second  sacral  spine  and  the  centre  of  the  sacro-iliac  joint.  In  this 
connection  it  may  be  noted  that  the  lowest  limit  of  the  spinal  membranes 
and  the  cerebrospinal  fluid  corresponds  to  the  second  (or  third)  sacral 
spine  and  the  upper  border  of  the  great  sacrosciatic  notch.  The 
spine  of  the  ischium  is  on  a  level  with  the  first  piece  of  the  coccyx. 
The  level  of  the  upper  border  of  the  great  trochanter  is  about  2  cm. 
(f  in.)  below  the  top  of  the  femoral  head,  at  or  just  below  the 
centre  of  the  hip  joint,  and  nearly  on  a  level  with  the  pubic  spine. 
The  atrophy  of  the  gluteus  medius  and  minimus  muscles,  which  fill 
up  the  hollow  between  the  ilium  and  the  trochanter  and  render  the 
prominence  of  the  latter  comparatively  slight,  makes  the  trochanter 
very  conspicuous. 

Nelaton's  line,  which  is  drawn  from  the  anterior  superior  iliac  spine 
to  the  most  prominent  part  of  the  tuber  ischii,  normally  crosses  the 
centre  of  the  acetabulum  and  touches  the  top  of  the  great  trochanter 
in  the  extended  position.  Its  relation  to  the  trochanter  is  used  in  the 
diagnosis  of  fractures  of  the  neck  of  the  femur,  dislocations  of  the  hip 
and  late  stages  of  hip-joint  disease,  in  which  the  trochanter  is  displaced 
upward.  A  still  more  convenient  line  for  this  purpose  is  Bryant's  line, 
the  upper  line  of  Bryant's  triangle.  This  line  is  drawn  vertically  back- 
ward (in  the  horizontal  posture)  from  the  anterior  superior  iliac  spine, 
and  the  distance  from  this  line  to  the  top  of  the  great  trochanter,  as 
compared  with  that  on  the  opposite  side,  indicates  any  displacement 
upward  of  the  trochanter.  Rob  son's  line  is  practically  the  same,  and  is 
drawn  vertically  from  the  anterior  superior  spine  to  a  transverse  line 
touching  the  top  of  the  great  trochanter. 

Position  of  the  Vessels  and  Nerves. — The  gluteal  artery  and  the 
nerve  just  below  it,  as  they  emerge  from  the  pelvis,  correspond  about 
to  the  middle  of  the  superior  border  of  the  sciatic  notch.  This  point 
is  indicated  by  the  junction  of  the  upper  and  middle  thirds  of  a  line 
drawn  from  the  posterior  superior  iliac  spine  to  the  top  of  the  great 
trochanter,  when  the  thigh  is  slightly  flexed  and  rotated  inward.  In- 
cising in  this  line,  and  splitting  the  gluteus  maximus  muscle,  the  top  of 
the  sciatic  notch  is  felt  for  and  the  vessel  is  there  found,  if  its  ligature 
is  required.  The  sciatic  artery,  with  the  great  sciatic  nerve  external 
to  it  emerges  from  the  sciatic  notch  at  a  point  corresponding  to  the 
junction  of  the  middle  and  lower  thirds  of  a  line  drawn  from  the  pos- 
terior superior  iliac  spine  to  the  outer  part  of  the  tuber  ischii.  This 
line  crosses  the  posterior  inferior  iliac  spine  5  cm.  (2  in.)  below  the  upper 
end  and  the  ischial  spine  10  cm.  (4  in.)  below.  The  latter  spine  is  crossed 
by  the  internal  pudic  artery  as  it  passes  from  the  great  to  the  small 
sacrosciatic  foramen. 


THE  POSTERIOR  OR  GLUTEAL  REGION  4S7 

The  Great  Sciatic  Nerve. — The  great  seiatie  nerve,  emerging  from  the 
pelvis  at  the  point  mentioned,  passes  thence  down  the  middle  of  the  back 
of  the  thigh  in  a  line  to  the  middle  of  the  popliteal  space,  and  crosses  the 
line  from  the  tuber  ischii  to  the  outer  side  of  the  great  trochanter  at  the 
junction  of  its  middle  and  inner  thirds.  At  this  point  the  nerve  emerges 
from  beneath  the  lower  border  of  the  gluteus  maximus  and  is  most 
accessible,  being  covered  only  by  the  skin  and  fascia,  before  it  is  crossed 
by  the  long  head  of  the  biceps.  It  may  be  exposed  by  an  incision  having 
this  point  as  its  centre  and  running  either  in  the  line  of  the  nerve  or  along 
the  lower  border  of  the  gluteus  maximus,  across  this  line.  The  latter 
muscle  is  retracted  upward  and  outward  and  the  nerve  is  found  as  a 
white  cord  in  the  loose  tissue  separating  this  muscle  from  the  hamstring 
muscles.  This,  its  most  superficial  point,  is  apt  to  be  a  "tender  point" 
in  sciatica  (see  also  page  489). 

We  may  now  study  this  region  by  layers.  The  skin  is  thick,  coarse,  and 
firmly  connected  with  the  underlying  fascia,  so  that  it  is  not  freely  movable. 
It  is  often  the  seat  of  furuncles,  which  are  apt  to  be  very  painful,  owing 
to  its  plentiful  nerve  supply.1  The  subcutaneous  tissue  contains  a  large 
amount  of  fat,  to  which,  even  more  than  to  the  development  of  the  glu- 
teus maximus,  the  buttocks  owe  their  prominence  and  roundness.  This 
tissue  is  a  favorite  site  for  lipomata,  and  its  laxity  allows  large  effusions 
of  pus  and  blood  to  occur. 

The  Deep  Fascia. — The  deep  fascia  is  attached  to  the  iliac  crest  above, 
the  sacrum  and  coccyx  mesially,  and  splits  to  inclose  the  gluteus  maximus 
in  a  sheath.  The  deep  layer  of  this  sheath  covers  the  gluteus  medius, 
over  which  the  fascia  is  thicker  than  over  the  maximus,  especially  in 
front  of  the  latter.  By  means  of  this  fascia  the  glutei  medius  and 
minimus  are  enclosed  in  an  osseo-aponeurotic  space,  which  is  only 
open  below  toward  the  thigh  and  internally  toward  the  pelvis  at  the 
sciatic  foramina.  Effusions  of  blood  or  pus  pent  up  in  this  space  press 
upon  the  contained  nerves  and  explain  the  severe  pains  associated  with 
them.  Such  abscesses  may  extend  into  the  pelvis  or  a  pelvic  abscess 
may  extend  into  this  space,  through  the  sciatic  foramina.  Pus  or  blood 
beneath  the  deep  fascia  often  travels  for  some  distance  down  the  thigh 
before  it  <;m  reach  the  surface,  and  in  one  case,  related  by  Farabeuf, 
the  abscess  reached  the  ankle  before  it  broke.  Extravasations  of  blood 
beneath  tin-  fascia  may  fluctuate  and  be  mistaken  for  abscess,  as  they 
may  occur  without  any  discoloratioD  of  the  skin,  at  least  for  some  time, 
and  then  perhaps  at  some  distance  down  the  thigh.  Tli£  deep  or  gluteal 
fascia  is  continuous  below  with  the  fascia  lata  of  the  thigh,  and  later- 
ally with  that  thickened  pari  of  it  known,  from  its  attachments,  as  the 
iliotibial  band.      Tin-  latter    i  the  insertion  of  the  tensor  vaginae 

femoris  and  the  anterior  expanded  pari  of  the  gluteus  maximus  ten- 
don, both  of  which  increase  the  thickness  of  the  band.    Across  the 

p  between  the  iliac  cresl  and  the  great  trochanter  this  Wand  is  tightly 

includee  fil  ion  ol  *lii-  liinilj.'ir  .-mil  Micial  oervM,  the  lateral 

branch  >>i  the  last  thoi  'in-  iliac  brush  of  the  LUohypogaetrk  nerve,  large 

brunch'  end  flliunenl  tenia]  outaoeoua  nerve. 


4gg  THE  LOWER  EXTREMITY 

stretched,  so  as  to  firmly  resist  the  pressure  of  the  fingers.  If,  however, 
the  trochanter  is  raised  this  band  is  relaxed,  a  fact  that  may  be  useful 
in  the  diagnosis  of  fractures  of  the  neck  of  the  femur,  etc. 

The  Muscles. — The  muscles  of  the  buttocks  may  be  divided  into 
three  layers,  between  the  outer  of  which,  consisting  of  the  gluteus  maxi- 
mus,  and  the  middle,  comprising  the  gluteus  medius,  pyriformis,  obtura- 
tor internus  and  quadratus  femoris,  lie  most  of  the  important  nerves  and 
vessels.  Most  incisions  in  this  region  are  made  parallel  with  the  fibers  of 
the  gluteus  maximus,  which  run  obliquely  downward  and  forward.  This 
muscle  may  then  be  split  instead  of  cut.  The  gluteus  maximus  does  not 
act  to  maintain  the  erect  position,  but  only  in  rising  to  that  position,  in 
climbing  stairs,  etc.,  in  jumping,  and  in  carrying  heavy  weights  on  the 
back.  Hence  when  this  muscle  is  paralyzed  the  patient  can  walk  on  a 
level  surface,  but  has  difficulty  in  rising  from  a  seat,  in  climbing  stairs, 
etc.  In  paralysis  of  the  gluteus  medius  there  is  difficulty  in  maintain- 
ing the  erect  position  on  the  side  paralyzed. 

Of  the  bursae  in  this  region,  three  at  least  are  over  the  great  tro- 
chanter, separating  the  latter  from  each  of  the  three  gluteal  muscles. 
Only  that  between  the  trochanter  and  the  gluteus  maximus  is  of  much 
practical  importance,  for  it  may  be  inflamed  and  render  painful  the 
movements  of  the  thigh.  Hence  in  the  inflammation  of  this  bursa  the 
thigh  is  kept  flexed  and  adducted,  to  rest  or  relax  the  gluteal  muscles, 
whose  action  is  to  extend  and  abduct  it.  A  bursa  over  the  tuber  ischii 
separates  that  process  from  the  skin  and  subcutaneous  tissues,  in  the 
sitting  posture  (see  pp.  394  and  485).  Among  those  whose  occupa- 
tion requires  much  sitting  this  bursa  is  often  inflamed  and  enlarged, 
forming  what  is  known,  according  to  circumstances,  as  "weaver's," 
"coachman's,"  "drayman's,"  or  "lighterman's"  "bottom."  When 
enlarged  it  may  press  upon  the  inferior  pudendal  nerve. 

Vessels. — The  gluteal  artery  is  usually  the  largest  of  this  region,  being 
of  the  size  of  the  ulnar,  hence  its  wounds  are  serious  and  have  been 
rapidly  fatal.  Wounds  of  this  artery  usually  involve  only  its  branches, 
for  the  portion  of  its  trunk  outside  of  the  pelvis  is  not  longer  than 
5  mm.  (Bouisson).  Hence  in  place  of  extrapelvic  ligature  of  the  vessel 
for  aneurysm,  ligation  of  the  internal  iliac  artery  is  usually  performed. 
Gluteal  aneurysm  is  not  very  uncommon.  To  cure  it,  compression  of 
the  internal  iliac  artery,  through  the  rectum,  has  been  tried  by  Dr. 
Sands  (Am.  Jour.  Med.  Sci.,  1881),  but  not  effectively.  If  the  aneurysm 
involves  the  trunk  of  the  gluteal  artery,  which  runs,  near  its  commence- 
ment, between  the  lumbosacral  cord  and  the  first  sacral  nerve,  nerve 
symptoms  from  pressure  can  hardly  fail  to  occur.  The  gluteal  and 
sciatic  arteries  can  be  and  have  been  ligated  for  wounds,  through  an 
incision  in  the  buttocks  over  their  course  (see  p.  486).  The  size  of 
the  accompanying  veins  and  their  close  attachment  to  the  artery  increase 
the  difficulty  of  ligation  of  the  gluteal  artery.  There  are  several  cases 
recorded,  of  which  Henle  collected  six,  where  the  greatly  enlarged  sciatic 
artery,  running  alongside  of  the  sciatic  nerve,  took  the  place  of  the  femoral 
artery  to  the  popliteal  space,  in  the  absence  of  the  latter  vessel.     The 


PLATE  XLVII 


FIG.  167 


POSTERIOR- 


LUTEAL    ARTERY 


UP.    GLUTEAL 

NERVE 
NF.    GLUTEAL 

NERVE 
CIATIC    ARTERY 
NT.     PUDIC 

ARTERY 
NT.     PUDIC 

NERVE 
MALL    SCIATIC 

NERVE 
REAT   SACRO-SCIATIC 

LIGAMENT 
REAT    SCIATIC 
NERVE 


Gluteal    Region   of  the  Left  Side   after   Removal   of  the   Gluteus 
Maximus  and  Part  of  the  Gluteus  Medius.     (Joessel.) 


THE  ANTERIOR  OR  SUB1NGUINAL  REGION  489 

sciatic  artery  is  most  important  in  the  collateral  circulation  after  ligature 
of  the  femoral. 

The  superficial  lymphatics  of  the  buttocks  run  to  the  inguinal  nodes, 
the  deep  lymphatics  accompany  the  bloodvessels  to  the  internal  iliac 
or  hypogastric  nodes  after  traversing  some  small  and  inconstant  nodes 
beneath  the  pyriformis  muscle. 

The  Great  Sciatic  Nerve. — The  great  sciatic  nerve,  after  emerg- 
ing from  the  pelvis  at  the  point  indicated  above,  is  covered  by  the  gluteus 
maximus  and  lies  upon  the  obturator  internus  and  the  quadratus  femoris. 
In  spite  of  its  close,  relation  to  the  hip-joint,  it  is  almost  never  injured  in 
hip-joint  dislocations.  In  two  or  three  cases  only  it  has  been  hooked  up 
in  front  of  the  head  of  the  femur.  Neuralgia  in  this  nerve  is  known  as 
sciatica,  a  condition  due  to  a  variety  of  causes.  Within  the  pelvis  aneurysm 
of  some  of  the  branches  of  the  internal  iliac  artery,  engorgement  of 
some  of  the  pelvic  veins  lying  in  front  of  it  (Erb),  fecal  accumulation 
in  the  rectum,  the  fetal  head  in  tedious  labors  and  various  forms  of 
pelvic  tumor,  usually  palpable  through  the  rectum,  may  cause  sciatica 
by  pressure.  Pelvic  or  spinal  tumor  should  be  suspected  in  the  pres- 
ence of  a  double  sciatica.  Outside  of  the  pelvis  it  is  near  enough  to  the 
surface  to  be  affected  by  cold. 

Stretching  the  nerve  has  been  employed  in  the  treatment  of  this  con- 
dition, for  excision  is  unjustifiable  owing  to  its  great  importance.  The 
so-called  bloodless  or  dry  stretching  consists  in  forcibly  flexing  the  hip 
while  the  knee  is  kept  extended.  But  this  stretches  not  only  the  nerve, 
but  also  the  hamstring  muscles,  hence  wet  stretching  is  usually  employed, 
the  nerve  being  first  exposed  by  an  incision  (see  pp.  487  and  510).  Trom- 
betta  found  that  a  weight  of  183  pounds  was  required  to  break  the  great 
sciatic  nerve,  representing  a  force  not  likely  to  be  equalled  in  stretching. 
But  the  nerve  can  be  torn  away  from  the  soft  spinal  cord  by  a  force  not 
at  all  sufficient  to  rupture  the  nerve,  hence  care  must  be  exercised  in 
making  traction  on  its  proximal  side.  A  safe  rule  is  to  use  only  enough 
force  to  raise  the  limb  from  the  table,  the  patient  being  in  the  prone 
position. 

The  possibility  of  wounding  the  pelvic  viscera  through  the  sciatic 
foramina,  in  wounds  of  the  buttocks,  should  be  remembered.  Treves 
mentions  a  fatal  case  of  peritonitis  due  to  a  stab  wound  of  the  bladder 
through  the  buttock,  and  the  rectum  has  been  injured  in  like  manner. 
We  operate  upon  the  pelvic  viscera  through  the  great  sacrosciatic  foramen 
after  division  of  the  great  sacrosciatic  ligament,  with  or  without  removal 
of  the  coccyx  and  part  of  the  sacrum.  The  former  is  the  method  of 
Kraske  in  resection  of  flic  rectum. 


The  Anterior  or  Subinguinal  Region,  the  Region  of  Scarpa's 

Triangle. 

This  is  bounded  above  \>y  Poupart's  ligament,  below  by  a  line  12  to 
1  '>  (in.  (5  to  6  in.)  below  it,  on  a  level  with  the  gluteal  fold. 


490  THE  LOWER  EXTREMITY 

Surface  Markings  and  Landmarks. — The  anterior  superior  iliac 
spine,  the  pubic  spine,  and  Poupart's  ligament  are  most  important 
landmarks  and  readily  made  out  (see  p.  268).  The  sartorius  muscle 
is  rendered  visible  or  palpable  when  the  thigh  is  raised  and  adducted, 
the  adductor  longus  when  it  is  adducted  in  spite  of  resistance.  The 
former  runs  obliquely  downward  and  inward  from  the  anterior  supe- 
rior iliac  spine,  the  latter  downward  and  outward  from  just  below  the 
pubic  spine,  hence  it  may  be  used  as  a  guide  to  that  spine  in  stout 
females.  These  two  muscles,  crossing  12  to  15  cm.  (5  to  6  in.)  below 
Poupart's  ligament  (10  cm.  [4  in.]  in  muscular  subjects),  bound,  with 
the  latter,  Scarpa's  triangle.  This  triangle  may  appear  as  a  slight  hollow 
below  the  fold  of  the  groin.  In  thin  subjects  the  superficial  inguinal 
lymph  nodes  can  be  felt  near  the  base  of  the  triangle;  if  enlarged  they  are 
readily  felt.  In  emaciated  subjects  a  prominence  sometimes  appears 
below  the  outer  half  of  Poupart's  ligament,  corresponding  to  the  head 
of  the  femur,  which  may  be  indistinctly  felt  in  extension  and  outward 
rotation  of  the  thigh. 

Topography. — The  femoral  ring  lies  on  the  horizontal  line  connect- 
ing the  pubic  spine  and  the  top  of  the  great  trochanter,  2.5  cm.  (1  in.) 
from  the  former.  It  is  also  12  mm.  (^  in.)  internal  to  the  femoral  artery 
just  below  Poupart's  ligament.  The  artery  is  a  little  internal  to  the 
middle  of  the  ligament,  or  midway  between  the  anterior  superior  iliac 
spine  and  the  symphysis.  From  thence  the  line  of  the  artery  is  drawn  to 
the  adductor  tubercle,  or  the  back  of  the  inner  condyle,  the  thigh  being 
slightly  flexed  and  abducted.  The  upper  two-thirds  of  this  line  corre- 
sponds to  the  position  of  the  femoral  artery.  Its  profunda  branch  is  given 
off  about  3.5  cm.  (1^  in.)  below  Poupart's  ligament,  and  the  artery  is 
covered  by  the  sartorius  about  7.5  to  10  cm.  (3  to  4  in.)  below  the  same 
point.  The  femoral  vein  bears  a  relation  to  the  artery  just  the  reverse  of 
the  sartorius  muscle  throughout  its  extent.  The  saphenous  opening  lies 
with  its  centre  3.5  cm.  (1^  in.)  below  and  also  external  to  the  pubic  spine, 
where  its  position  is  sometimes  indicated  by  a  slight  depression.  In  those 
without  much  subcutaneous  fat  the  long  saphenous  vein  can  be  seen  or 
felt  running  up  to  the  saphenous  opening.  This  vein  penetrates  the 
cribriform  fascia  to  join  the  femoral  vein  3  to  4  cm.  (1-g-  to  If  in.)  below 
Poupart's  ligament.  Just  below  its  passage  through  the  fascia  it  some- 
times presents  a  dilatation  which  might  even  be  mistaken  for  a  femoral 
hernia.  This  vein  and  its  tributaries  are  often  the  seat  of  varices, 
commonly  the  result  of  congenital  conditions.  Trendelenburg's  opera- 
tion for  varicose  veins  of  the  leg  consists  of  the  double  ligature  and  divi- 
sion of  this  vein  just  below  its  upper  end. 

The  Skin. — The  skin  is  thin  and,  below  Poupart's  ligament,  very 
movable  on  account  of  its  loose  attachment.  Incisions  parallel  with 
Poupart's  ligament  do  not  gape,  hence  in  opening  abscesses  here  a 
vertical  incision  affords  better  drainage  by  reason  of  the  resulting  separa- 
tion of  the  edges.  After  burns  and  other  loss  of  substance  of  the  skin  of 
this  region,  the  resulting  cicatrix  may  cause  flexion  of  the  hip  by  cicatricial 
contraction.     Supernumerary  mammary  glands  are  sometimes  found  in 


THE  ANTERIOR  OR  SUBINGUINAL  REGION 


491 


this  region,  and  Treves  refers  to  a  case,  related  by  Jessieu,  of  a  woman 
who  nursed  her  child  from  a  breast  so  placed. 

The  Superficial  Fascia. — The  superficial  fascia  is  usually  described 
in  two  layers,  of  which  the  superficial  one  contains  the  subcutaneous  fat, 
which  may  be  so  thick  as  to  make  operations  here  more  difficult.  This 
region  is  a  favorite  situation  for  fatty  tumors  in  the  superficial  fascia, 
which  here  show  a  tendency  to  travel  in  the  direction  of  gravity,  owing 
to  the  looseness  of  the  tissue  and  of  the  attachment  of  the  capsule  of 
the  tumor. 

Between  the  two  layers  are  the  superficial  inguinal  nodes.  They  may 
be  conventionally  divided  into  four  groups,  by  a  vertical  and  a  hori- 
zontal line  drawn  through  the  point  where  the  long  saphenous  vein 


Fig.  168 


SUPERIOR 
EXTERNAL 

lOUP 


SUPERIOR 

INTERNAL 

GROUP 

INFERIOR 

INTERNAL 

GROUP 


INFERIOR 
EXTERNAL 
GROUP 


r  icial  inguinal  glands.      Cribriform  fascia  has  been  removed  so  as  ,to  expose  the 
femoral  vessels.      (Poirier  and  Charpy.) 


pierces  the  cribriform  fascia.  The  upper  two  groups  correspond  more 
n  less  with  the  convenient  subdivision,  the  horizontal  group,  lying  just 
below  and  parallel  with  Poupart's  ligament,  the  lower  two  groups  with 
the  vertical  group, parallel  with  and  along  the  Long  saphenous  vein.  The 
jrertical  group  receives  lymphatics  from  the  surface  of  the  lower  extremity, 
the  perineum,  and  some  from  the  external  genitals  and  the  inner  pari  of 
die  buttocks.  The  horizontal  nodes  from  without  inward  receive  the 
lymphatics  of  the  outer  part  of  the  buttocks,  the  lower  abdomen,  the 
e\t.  in;,!  genitals,  and  the  inner  pari  of  the  buttocks.  Although  this  is 
true  in  a  general  way,  yet  do  node-,  constantly  receive  a  definite  set  of 
lymphatics,  and  all  the  node.-,  are  connected  in  a  plexiform  manner. 
How<    '  i,  when  these  glands  arc  enlarged  or  are  the  seat  of  abscess,  as 


492  THE  LOWER  EXTREMITY 

often  occurs,  we  should  look  to  the  parts  named  for  the  primary  lesion. 
The  efferents  of  the  superficial  nodes  pass  to  the  deep  inguinal  and  iliac 
nodes. 

The  cribriform  fascia  is  variously  described.     English  and  American 
authors,  for  the  most  part,  consider  it  as  belonging  to  the  deep  layer 
of  the  superficial  fascia  and  as  covering  an  oval  area  which  is  supposed 
to  intervene  between  the  anterior  or  iliac  portion  and  the  deeper  or 
pectineal    portion  of  the  fascia    lata.     German  and  French   authors 
consider  it  as  a  part  of  the  deep  fascia  (fascia  lata)  which  divides  below 
Poupart's  ligament  into  two  triangular  layers,  one  of  which  passes  in 
front  and  the  other  behind  the  femoral  vessels  to  unite  together  exter- 
nally in  front  of  the  iliopsoas,  internally  in  front  of  the  pectineus  and  below 
around  the  sheath  of  the  vessels,  3  to  4  cm.  (1|  to  If  in.)  below  Poupart's 
ligament.     In  either   case   the   cribriform   fascia  refers  to  the  fascia 
covering  an  oval  area,  the  fossa  ovalis  or  saphenous  opening,  measuring 
2.5  cm.  (1  in.)  in  its  long  or  vertical  diameter.     This  fascia  is  thin  and 
perforated  by  superficial  bloodvessels,  lymphatic  vessels  passing  from 
the  superficial  to  the  deep  nodes,  and,  at  its  lower  end,  by  the  long 
saphenous  vein  as  it  passes  back  to  empty  into  the  femoral  vein.     The 
perforations  give  rise  to  the  name  cribriform   (sieve-like)  fascia.     It 
lies  immediately  in  front  of  the  lower  end  of  the  femoral  canal,  forms  one 
of  the  coverings  of  a  femoral  hernia,  offers  little  resistance  to  the  passage 
of  pus,  and  on  it  lie  some  of  the  superficial  lymph  nodes.     The  femoral 
canal  and  the  vascular  and  muscular  compartments  have  been  already 
referred  to   (see  pp.  302-3).     The   density  of  the  deep  fascia   (fascia 
lata)  affects  the  extension  of  underlying  growths  and  abscesses  and  the 
opening  of  the  latter.     If  a  psoas  abscess  breaks  through  the  sheath  of 
the  iliopsoas  muscle  below  Poupart's  ligament,  it  may  travel  in  the  line 
of  gravity  far  down  the  thigh  before  it  opens  on  the  surface.     The 
firmness  of  this  fascia  also  modifies  the  surface  appearance  and  feel  of 
underlying  growths. 

Within  Scarpa's  triangle,  and  at  a  deeper  level,  is  a  second  triangle 
or  a  groove  between  the  iliopsoas  and  the  pectineus  (fossa  iliopectinea), 
in  which  lie  the  femoral  vessels.  The  iliopsoas  and  an  underlying  layer 
of  fatty  and  areolar  tissue  intervenes  between  the  vessels  and  the  hip 
joint  so  that  in  amputation  at  or  excision  of  the  hip  joint  the  vessels  are 
protected  from  injury  in  freeing  the  head  of  the  bone.  Between  the 
iliopsoas  muscle  and  the  thinnest  part  of  the  capsule  of  the  hip  is  a  bursa 
which  may  communicate  with  the  joint.  This  "psoas  bursa"  may  form 
a  large  visible  tumor  below  the  middle  of  Poupart's  ligament,  when 
chronically  inflamed.  Inflammation  of  this  bursa  may  extend  to  the 
hip  joint,  or  vice  versa.  It  causes  flexion  of  the  thigh,  to  relieve  the 
pressure  of  the  muscle  on  the  bursa  and  on  account  of  reflex  irritation 
of  the  iliopsoas.  Sprain  or  even  partial  rupture  of  one  or  more  of  the 
adductor  group  of  muscles,  especially  the  adductor  longus,  often  occurs 
in  horseback  exercise.  The  lesion  is  usually  close  to  their  pelvic  attach- 
ments. It  may  be  accompanied  by  much  effusion  of  blood,  and  may 
sometimes  be  followed  by  the  ossification  of  the  tendon  of  the  adductor 


PLATE  XLVIII 


FIG.    169 


LIAC    FASCIA 

ANTERIOR 
CRURAL 
NERVE 


FASCIA    LATA 

INTERNAL 

SAPHENOUS 

VEIN 
PROFUNDA 

FEMORIS 

ARTERY 


Region  of  Scarpa's  Triangle,  leftside.     (Joessel.) 


THE  ANTERIOR  OR  SUBINGUINAL  REGION  493 

longus  or  magnus,  to  the  extent  of  1  to  7.5  cm.  (£  to  3  in.),  a  condition 
known  as  "rider's  bone,"  and  seen  most  often  in  cavalrymen. 

Vessels. — The  femoral  artery  bisects  Scarpa's  triangle  from  its  base 
to  its  apex.  The  line  of  its  course  has  already  been  given.  Where  it 
crosses  the  pelvic  margin,  just  below  Poupart's  ligament  and  3^  cm. 
(H  in.)  external  to  the  pubic  spine  (Richet),  it  is  only  separated  from 
the  iliopectineal  eminence  by  a  thin  layer  of  the  iliopsoas.  Hence 
compression  of  the  artery,  which  has  often  been  successful  in  popliteal 
aneurysm,  is  here  most  easily  made  by  pressure  backward.  A  little 
lover  it  lies  in  front  of  the  head  of  the  femur,  from  which  it  is  separated 
by  a  thicker  layer  of  the  iliopsoas.  Still  lower  it  lies  in  front  of  and 
internal  to  the  neck  of  the  femur  and  the  hip  capsule.  In  applying 
pressure  to  the  artery  we  should  avoid  pressure  on  the  vein  internal  to 
it,  because  of  the  possible  danger  of  phlebitis.  The  anterior  crural  nerve 
is  separated  from  the  artery  by  the  iliac  fascia,  so  that,  although  it  lies 
only  G  mm.  (\  in.)  external  to  it,  just  below  Poupart's  ligament,  it  is 
not  in  much  danger  of  injury  by  pressure  in  compression  of  the  artery. 

The  length  of  the  common  femoral  artery,  or  that  part  above  the  pro- 
funda, may  practically  be  taken  to  be  the  distance  between  the  origins 
of  the  deep  epigastric  and  of  the  profunda  femoris  branches.  Although 
this  is  about  4  cm.  (If  in.)  in  the  majority  of  cases,  Vignerie  found  that 
in  about  16  per  cent,  the  distance  was  2  cm.  (-f  in.)  or  less.  The  common 
femoral  may,  therefore,  be  so  short  as  to  render  its  ligature  difficult. 
Before  the  days  of  antisepsis  and  asepsis  the  nearness  of  a  large  collat- 
eral branch  was  most  important  in  the  ligature  of  large  arteries,  on  account 
of  the  danger  of  secondary  hemorrhage  if  the  wound  became  infected,  so 
that  it  was  advised  to  tie  the  external  iliac  instead  of  the  common  fem- 
oral, when  ligature  of  the  latter  was  indicated.  Nowadays  a  long  clot, 
or  indeed  any  clot,  between  the  point  of  ligature  and  the  nearest  large 
branch  is  not  considered  necessary,  so  that  this  objection  to  tying  the 
common  femoral  no  longer  holds  good.  However,  the  femoral  is  com- 
mon/;/ ligaied  at  the  apex  of  Scar  pa's-  triangle,  unless  ligature  at  this  point 
is  contra-indicated.  Here  the  sartorius  crossing  it  serves  as  a  guide, 
the  vein  is  behind  and  somewhat  adherent,  the  saphenous  vein  is  internal, 
and  the  long  saphenous  nerve  is  external.  The  femoral  artery,  from  its 
superficial  position  in  Scarpa's  triangle,  is  liable  tobe  wounded.  Aneurysm 
is  relatively  common  in  the  common  femoral,  for  the  artery  is  affected  by 
the  movements  of  the  hip,  is  exposed  to  injury  from  its  superficial  posi- 
tion, and  it  bifurcates  into  two  large  trunks.     Arteriovenous  aneurysms 

from  wounds  may  also  occur  here. 

the  tributaries  of  the  common  femoral  vein,  or  that  portion  of  the 
femoral  vein  above  the  entrance  of  the  long  saphenous  vein,  are  pro- 
vided with  valves  which  should  normally  prevent  the  backward  flow 
from  the  femoral  through  U>  tributaries  to  the  tributaries  of  the  pelvic 

vein,  anastomosing  with   them,  it   would  appear  as  if  the  femoral  vein 
lie  only  outlet    to   the  pelvis  of  the  blood  of  the  lower  extremity. 

Prom  tin,  premise  it  was  argued  thai  the  ligature  of  tin-  common  femoral 

vein   alone    would    had    to   gangrene,   and    should    not    be  done    without 


494  THE  LOWER  EXTREMITY 

simultaneous  ligature  of  the  artery,  to  prevent  the  inflow  of  too  much 
blood  into  the  limb.  In  fact,  formerly  many  ligated  the  artery  only  in 
case  of  a  wound  of  the  vein.  But  many  cases  of  isolated  ligature  of  the 
common  femoral  vein  are  on  record  without  gangrene  resulting.  In 
fact,  Braun  found  from  statistics  that  the  ligature  of  the  common  femoral 
vein  alone  was  less  often  followed  by  gangrene  of  the  extremity  than  either 
ligature  of  the  artery  alone  or  of  both  artery  and  vein.  Experimentally 
Braun  found  that  in  85  per  cent,  the  valves  of  the  tributaries  gave  way 
before  a  pressure  of  180  mm.  of  mercury.  The  greater  the  pressure 
the  better  the  chance  of  venous  collateral  circulation,  hence  the  artery 
should  not  be  ligated,  unless  necessary,  in  order  to  increase  the  pressure 
in  the  veins.  According  to  Richet  and  Verneuil  the  collateral  circula- 
tion occurs  especially  between  the  external  pudic  veins  and  the  veins 
of  the  pelvis  and  between  the  internal  circumflex  veins  and  the  veins  of 
the  buttocks.  It  is  quite  probable  that  there  are  more  collateral  anas- 
tomoses than  are  known,  and  that  the  valves  are  often  wanting  or  insuffi- 
cient. In  wounds  of  this  vein  lateral  ligature  has  been  successful  in  a 
number  of  cases  and  should  be  employed  when  possible. 

Thrombophlebitis  involves  the  femoral  vein  not  infrequently  as  a  sequela 
of  typhoid  and  other  fevers,  as  well  as  of  operations  like  appendectomy, 
hysterectomy,  etc.,  even  when  they  are  apparently  aseptic.  The  cause  is 
probably  a  slight  degree  of  infection,  a  sluggish  circulation,  the  dependent 
position  of  the  part  in  bed,  and  in  fevers  the  altered  constitution  of  the 
blood;  and  the  result  is  pain,  usually  followed  by  edema  of  the  leg. 

The  deep  lymphatic  nodes,  one  to  three  in  number,  lie  in  front  of  and 
internal  to  the  femoral  vein,  and  receive  the  deep  lymphatics  of  the  lower 
extremity.  The  upper  one,  the  node  of  Cloquet  (or  Rosenmiiller),  lies 
upon  the  septum  crurale  (see  p.  304),  and  really  belongs  to  the  iliac 
nodes.  The  pathology  of  elephantiasis,  which  is  more  common  in  the 
lower  extremity  than  elsewhere,  is  concerned  with  the  lymphatics  of  this 
region  which  are  obstructed  by  the  filaria  sanguinis  hominis,  a  small 
thread-worm.  This  obstruction  leads  to  an  enormous  increase  in  size 
of  the  extremity  from  distention  of  the  lymph  channels  and  hypertrophy 
of  the  connective  tissue. 

The  crural  branch  of  the  genitocrural  nerve  gives  sensory  filaments 
to  the  skin  over  Scarpa's  triangle,  the  irritation  of  which  causes  the 
"cremasteric  reflex,"  which  consists  of  the  retraction  of  the  testis,  and 
is  due  to  the  contraction  of  the  cremaster  muscle,  which  is  supplied  by 
the  genital  branch  of  this  nerve.  This  reflex  is  most  marked  in  children 
and  young  adults,  and  indicates  the  condition  of  the  second  lumbar 
segment  of  the  cord,  which  is  the  spinal  centre  of  this  nerve. 


THE  HIP  JOINT. 

Topography. — The  centre  of  the  acetabulum  lies  in  Nekton's  line,  on 
or  just  above  the  level  of  the  top  of  the  great  trochanter  and  a  little  below 
the  horizontal  level  of  the  upper  border  of  the  symphysis.     The  tuber 


THE  HIP  JOINT  495 

ischii  lies  below  and  behind  it.  The  centre  of  the  head  of  the  femur 
lies  about  5  cm.  (2  in.)  directly  below  the  anterior  inferior  iliac  spine, 
and  on  a  line  drawn  at  right  angles  to  the  centre  of  the  line  connecting 
the  anterior  superior  iliac  spine  and  the  spine  of  the  pubis,  about  5  cm. 
(2  in.)  from  the  latter  line.  At  this  point  it  may  sometimes  be  felt  in 
emaciated  subjects.  The  top  of  the  head  of  the  femur  is  18  mm.  (f  in.) 
above  the  upper  border  of  the  great  trochanter.  The  portion  of  the 
greed  trochanter  which  is  most  external  and  subcutaneous  is  about 
2..")  cm.  (1  in.)  below  its  upper  margin.  According  to  Hueter  the  top 
of  the  great  trochanter  is  relatively  higher  in  the  child,  owing  to  the 
relative  shortness  of  the  neck. 

The  cartilage-covered  portion  of  the  femoral  head  is  somewhat  more 
than  a  hemisphere,  and  has  a  radius  of  about  2.5  cm.  (1  in.).  The 
superior  and  anterior  aspects  of  the  head  are  rather  more  covered  by 
cartilage  than  the  inferior  and  posterior.  The  depression  for  the  liga- 
mentum  teres,  behind  and  below  the  centre  of  the  head,  is  a  little  below 
the  point  reached  by  the  prolongation  of  the  axis  of  the  neck.  The  articu- 
lar or  cartilage-covered  surface  of  the  acetabulum  is  horseshoe-shaped, 
12  to  25  mm.  (V  to  1  in.)  in  width,  and  encloses  a  thin,  non-articular 
ana  of  bone.  The  latter  area  is  seldom  fractured,  for,  in  spite  of  its 
thinness,  it  does  not  receive  the  direct  impact  of  the  femoral  head,  on 
account  of  the  shape  of  the  cavity.  According  to  Tillaux,  one  of  the 
chief  functions  of  the  ligamentum  teres,  as  indicated  by  its  oblique 
direction  upward  and  inward  from  the  acetabulum  to  the  head  of  the 
femur,  is  to  arrest  the  pressure  of  the  head  against  the  bottom  of  the 
acetabulum.  In  rare  eases  suppuration  in  the  hip  joint  may  reach  the 
pelvis,  or  vice  versa,  by  perforating  this  thin  area.  Before  the  eighteenth 
year,  when  the  Y-shaped  cartilage  uniting  the  three  bones  which 
meet  in  the  acetabulum  ossifies,  perforation  may  occur  through  the 
cartilage  and  the  acetabulum  may  be  broken  up  into  its  three  parts  by 
disease  or  injury.  The  bone  just  above  the  acetabulum  is  very  thick 
to  transmit  the  weight  of  the  trunk  to  the  head  of  the  femur  (seep.  397). 
The  acetabulum  measures  3  to  3.5  cm.  {\\  to  1^  in.)  in  depth  in  the 
male,  somewhat  less  in  the  female,  and  it  averages  5  cm.  (2  in.)  in  diam- 
eter at  its  rim. 

The  strength  of  the  hip  joint  depends  not  only  upon  the  shape  of  the 
biiiics,  but  also  on  the  strength  of  the  thickenings  of  the  capsule  and  of 
the  surrounding  mu  cles  and  tendons.  The  strongest  part  of  the  capsule 
i-,  the  iliofemoral  band  or  Y  ligament,  which  is  6  mm.  ( ',  in.)  (hick  in  its 
thickest  part,  and  is  one  of  the  strongest  ligaments  of  the  body,  being 
capable  of  sustaining  ;i  strain  of  from  251)  to  750  pounds  (Bigelow  ). 
This  ligament  is  of  the  utmost  importance  in  dislocations  of  the  hip 
joint  in  determining  both  the  position  of  the  limb  and  (he  mechanism 
of  reduction  by  manipulation,  and  it  is  almost  never  torn.  The  thinnest 
and  weakest  'parts  of  the  capsule  ace  on  either  side  of  the  pubofemoral 
band.      The  ihin    purl   in  front  of  and    external   to  il    is    just    below    and 

ial  to  the  iliopubic  eminence,  between  the  pubo-  and  iliofemoral 
bands,  and  under  the  bursa  between  the  iliopsoas  muscle  and  the  joint 


496 


THE  LOWER  EXTREMITY 


capsule.  There  is  often  a  defect  in  this  thin  area,  so  that  the  bursa  and 
the  joint  are  only  separated  by  synovial  membrane,  and  the  latter  is 
also  sometimes  wanting,  making  a  direct  communication  between  the 
two.  This  explains  how  pus  in  the  joint  can  readily  perforate  or  extend 
into  the  bursa  and  so  come  to  lie  beneath  the  iliopsoas,  and  also  how  a 
psoas  abscess  may  occasionally  invade  the  joint.  The  thin  area  behind 
and  internal  to  the  pubofemoral  band  is  at  the  lower  end  of  the  postero- 
internal part  of  the  capsule.  The  rupture  of  the  capsule  in  dislocation  of 
the  hip  occurs  most  commonly  in  this  area.  When  the  joint  is  distended 
with  effusion  the  swelling  naturally  first  appears  at  these  two  thin  areas, 
which  are  accessible  to  palpation  and  correspond  to  the  most  marked 

Fig.  170 


THIN  AREA  OFCAPSULE 

ON  WHICH    RESTS  THE 

BURSA    BENEATH    THE 

PSOAS 

PUBO-FEMORAL 

BAND 


DON    OF    REC- 
S    FEMORIS 

PERFICIAL  PART  OF 
LIO-FEMORAL  BAND 
DISSECTED    AWAY 


ILIO-FEMORAL 
BAND 


Ligaments  of  the  hip  joint  of  the  left  side.      Anterior  view.      (Joessel.) 


and  earliest  tenderness  and  swelling.  In  general  the  outer  (upper)  and 
anterior  parts  of  the  capsule  are  thick  and  strong,  the  inner  (lower)  and 
posterior  parts  thin  and  weak.  The  pressure  on  and  tension  of  the  cap- 
sule are  greatest  near  its  pelvic  attachment  where  the  head  impinges 
upon  it  most. 

The  cotyloid  ligament  closely  embraces  the  head  of  the  femur  external 
to  its  greatest  diameter,  and,  by  preventing  the  entrance  of  air,  holds 
the  head  in  place  by  atmospheric  pressure,  when  the  capsule  and  the 
surrounding  muscles  are  divided.  Hence  in  excision  or  amputation 
of  the  hip  joint  this  ligament  is  divided  to  permit  the  removal  of  the  head 
from  the  socket.  Opening  an  abscess  connected  with  the  hip  joint 
does  not  increase  the  risk  of  pathological  dislocation,  unless  the  abscess 


THE  HIP  JOINT  497 

also  communicates  with  the  space  between  the  head  and  the  socket  and 
has  destroyed  the  continuity  of  the  cotyloid  ligament  or  has  eroded 
the  head  embraced  by  it.  The  cotyloid  ligament  levels  over  the  slight 
depressions  of  the  margin  of  the  acetabulum,  where  the  pubis  joins  the 
ilium  and  the  latter  the  ischium.  Hence  these  slight  depressions  can 
have  no  influence  upon  the  mechanism  of  dislocation,  as  supposed  by 
Malgaigne. 

Xo  definite  function  is  agreed  upon  for  the  ligamentum  teres.  Ac- 
cording to  Hyrtl,  the  vessels  which  it  was  supposed  to  carry  to  the  head 
of  the  femur  do  not  reach  the  latter,  but  bend  around  into  the  efferent 
veins.  In  childhood  they  may  reach  and  nourish  the  head,  and  this  may 
be  its  chief  function.  Although  put  on  the  stretch  by  flexion  combined 
with  adduction  or  outward  rotation,  these  movements  are  limited  by 
other  and  stronger  ligaments  (vide  infra).  In  operations  it  must  first 
be  cut  before  the  head  can  be  removed  from  the  socket.  Unless  abnor- 
mally long,  it  is  always  torn  in  dislocations,  except  in  the  congenital 
variety,  in  which  it  is  lengthened,  even  to  6  or  8  cm.  (2^  to  3j  in.). 

Owing  to  the  direction  of  the  neck  of  the  femur  the  two  most  important 
movements  of  the  hip,  flexion  and  extension,  are  accompanied  by  a  rota- 
tion of  the  head  in  the  socket  without  its  projecting  far  from  the  latter  and 
thus  pressing  unequally  upon  the  capsule.  Hence  the  hip  joint  is  very 
secure  in  these  two  principal  movements.  In  the  other  movements  the 
head  projects  from  the  socket  on  the  side  opposite  that  toward  which 
the  movement  takes  place.  As  one  of  the  factors  leading  to  rupture 
of  the  capsule  is  the  pressure  of  a  projecting  portion  of  the  head  against 
a  weak  part  of  the  tense  capsule,  dislocation  is  not  likely  to  occur  during 
simple  flexion,  although  the  thin  posterior  part  of  the  capsule  is  then 
tense,  but  in  flexion  combined  with  adduction,  abduction,  or  rotation. 
In  rotation  the  head  projects  from  the  socket,  for  the  axis  of  rotation  does 
not  coincide  with  that  of  the  neck,  but  is  assumed  to  pass  through  the 
head  and  the  intercondylar  notch. 

The  movements  of  the  hip  joint  are  limited  as  follows:  Extension  by 
the  iliofemoral  band;  flexion  by  contact  of  the  soft  parts  in  the  groin 
when  the  knee  is  bent,  and  by  the  hamstring  muscles  when  the  knee 
tended;  abduetion  by  the  pubofemoral  band;  adduction  by  the  outer 
part  of  the  iliofemoral  band  and  capsule;  rotation  outward  by  the  ilio- 
femoral band  (its  inner  part  during  extension,  its  outer  part  during 
flexion);  rotation  inward  by  the  ischiofemoral  band,  and  in  addition 
by  the  iliofemoral  band,  during  extension. 

The  hip  joint,  owing  to  its  deep  position  and  thick  covering  of  soft 
parts,  is  not  very  liable  to  attacks  of  acute  inflammation  from  injury, 

■  Hie,  etc.,  to  which  other  joints  arc  liable.      It  seems,  however,  par- 
ticularly susceptible  t<>  chronic  inflammation.     Thus  it  is  a  favorite  site 

for  senile  rheumatoid,  arllirilis,  in  which  the  cartilages  ami  bony  surfaces 

are  eroded,  the  hitter  eburnated,  and  osteophytic  processes  developed 
around  the  joint  surfaces,  so  u  to  impede  its  movements. 

"Hip  Disease"  or  Coxitis.     Still   more  common  and  important  i 
the  occurrence  of  tuberculous  inflammation  of  the  joint  known  as  hip 


498  THE  LOWER  EXTREMITY 

disease  or  coxitis.  It  usually  begins  in  the  upper  epiphysis  or  the  syno- 
vial membrane.  Its  frequency  and  gravity  are  partly  accounted  for 
by  (1)  the  exposure  of  the  joint  to  strains  and  injury  on  account  of 
its  function  in  carrying  the  weight  of  the  body  and  in  locomotion;  (2) 
the  intracapsular  pressure,  which  is  easily  set  up  after  the  disease  has 
begun,  is  readily  increased  on  account  of  the  firmness  of  the  cap- 
sule and  the  strength  of  the  surrounding  muscles;  (3)  the  intracapsular 
position  of  the  upper  epiphysis.  In  the  great  majority  of  cases  it 
commences  in  early  childhood.  In  this  condition  there  is  swelling  and 
tenderness,  first  and  most  easily  demonstrable  beneath  the  middle  of 
Poupart's  ligament  and  behind  the  trochanter,  corresponding  to  the 
thinnest  parts  of  the  capsule  (pp.  495-6),  and  the  limb  assumes  certain 
characteristic  positions  at  various  stages. 

In  the  first  stage  the  thigh  is  flexed,  abducted,  and  slightly  everted. 
This  is  the  position  of  greatest  ease,  and  is  that  assumed  by  the  limb 
when  fluid  is  forcibly  injected  into  the  joint,  as  in  it  the  joint  holds  the 
most  fluid.  Hence  it  depends  upon  the  effusion  and  the  fact  that  the 
capsule  is  still  intact,  and  is  assumed  to  diminish  the  tension  and  thereby 
relieve  the  pain.  This  is  borne  out  by  the  fact  that,  in  cases  where  the 
primary  lesion  is  within  the  bone  and  there  is  no  effusion  at  first  into 
the  joint,  this  first  position  of  flexion,  abduction,  and  eversion  is  not 
observed,  but  the  limb  becomes  at  once  adducted  and  rotated  in.  The 
position  in  the  first  stage  relaxes  the  strongest  part  of  the  capsule,  the 
Y  ligament,  the  iliotibial  band,  and  the  iliopsoas  muscle.  According  to 
some  this  position,  as  well  as  that  assumed  later  on,  is  due  to  the  reflex 
contraction  of  muscles  which  are  supplied  by  branches  of  the  same 
nerves  that  supply  the  joint,  i.  e.,  anterior  crural,  obturator,  and 
branches  of  the  sacral  plexus. 

The  flexed  thigh  is  made  to  appear  straight  by  lordosis,  or  the  exten- 
sion of  the  lumbar  spine,  which  tilts  backward  the  pelvis  and  therewith 
the  femur  without  any  movement  in  the  sensitive  diseased  joint.  By 
flexing  the  sound  thigh  the  patient  can  then  stand  or  lie  with  both  limbs 
in  the  same  coronal  plane.  The  lordosis  can  be  detected  by  moving  the 
affected  thigh  when  the  patient  lies  on  a  table.  When  the  thigh  is  flexed 
to  the  angle  at  which  it  is  fixed  (in  flexion)  the  lordosis  disappears;  in 
other  words,  when  the  lordosis  is  made  to  disappear  the  degree  of  flexion 
is  shown.  If  we  continue  to  flex  the  thigh  the  spine  becomes  still  more 
straightened,  so  as  to  squeeze  the  hand  paced  between  it  and  the  table. 
When  the  thigh  is  again  extended  the  lordosis  can  be  felt  to  return. 

To  overcome  the  abduction  and  to  restore  the  parallelism  of  the  limbs, 
without  movement  in  the  diseased  and  painful  joint,  the  pelvis  is  tilted 
down  on  the  diseased  side  and  up  on  the  sound  side,  which  causes  a 
lateral  curvature  of  the  lumbar  spine  with  its  concavity  on  the  sound 
side.  This  would  abduct  the  sound  limb,  which  is  corrected  by  its  being 
adducted.  Owing  to  the  tilting  of  the  pelvis  the  diseased  side  is  lowered 
and  appears  lengthened,  the  sound  side  appears  shortened  (Fig.  137). 
If  the  tilting  of  the  pelvis  be  corrected,  the  limb  on  the  side  of  the  disease 
is  found  abducted,  the  sound  limb  adducted.    Hence  on  measurement 


THE  HIP  JOINT  499 

from  the  anterior  superior  iliac  spine  (see  p.  402)  we  get  measured  short- 
ening on  the  diseased  side,  though  at  this  stage  there  is  no  difference  in 
length.  The  measured  shortening  is  also  increased  by  the  flexion. 
Thus  we  get  apparent  lengthening,  measured  shortening,  and  real  equal- 
ity of  the  limb  on  the  affected  side  as  compared  with  the  opposite  side. 
This  is,  then,  the  stage  of  apparent  lengthening .  The  tilting  of  the  pelvis 
backward  and  downward  not  only  restores  the  parallelism  of  the  limbs, 
but  reduces  the  strain  on  the  muscles  and  ligaments  which  hold  the 
affected  limb  in  its  abnormal  position.  Muscular  wasting  is  usually  an 
early  symptom,  due  at  first  to  a  reflex  atrophy,  from  the  association  of 
the  nerves  of  the  joint  and  of  the  muscles,  and  later  due  to  disuse. 
The  thigh  and  gluteal  muscles  are  most  affected;  the  atrophy  of  the 
latter  exaggerates  the  obliteration  of  the  gluteal  fold. 

Second  Stage. — After  a  variable  time  the  capsule  becomes  softened,  so 
that  the  tension  is  diminished  and  the  thigh  becomes  adducted  and  rotated 
inward,  still  remaining  flexed.  This  is  probably  due  to  reflex  mus- 
cular contraction.  The  adductor  muscles  are  supplied  by  one  of  the 
principal  nerves  (obturator)  that  supply  the  hip  joint,  but  the  inversion 
is  perhaps  less  easily  accounted  for. 

Again  in  this  position,  to  conceal  the  adduction  and  to  restore  the  paral- 
lelism of  the  limbs,  the  pelvis  is  tilted  up  on  the  affected  side  and  the 
opposite  thigh  is  abducted,  causing  a  lateral  curvature  of  the  lumbar 
spine  with  its  concavity  on  the  diseased  side.  Hence  there  is  apparent 
shortening  and  measured  lengthening  (in  adduction)  on  the  sound  side. 
The  actual  length  of  the  limb  may  or  may  not  be  affected,  but  if  the  disease 
progresses  the  limb  is  shortened  by  the  absorption  of  the  head  of  the 
bone,  or  by  its  dislocation  onto  the  dorsum  ilii.  This  dislocation  is 
favored  by  the  erosion  of  the  upper  and  posterior  margin  of  the  ace- 
tabulum, and  the  softening  of  the  capsule.  This,  then,  is  the  stage  of 
apparent  shortening  and  later,  perhaps,  of  real  shortening. 

On  account  of  the  deep  position  of  the  hip  joint,  pus  found  in  the 
course  of  hip  disease  does  not  soon  reach  the  surface,  but,  remaining 
pent  up,  it  is  apt  to  burrow  in  various  directions  and  become  very 
destructive  in  its  results.  Intra-articular  abscess  may  work  forward 
through  the  thin  part  of  the  capsule  to  a  point  beneath  the  tensor  vaginae 
femoris,  or  backward  through  the  thin  part  of  the  capsule,  beneath  the 
gluteal  muscles,  to  a  point  behind  the  trochanter,  or  through  the  cotyloid 
notch  to  the  region  of  Scarpa's  triangle,  or  through  the  acetabulum  into 
the  pelvis.  The  epiphysis  that  forms  the  head  is  wholly  within  the 
joint,  and  the  conjugal  cartilage  that  unites  it  with  the  diaphysis,  and 
ossifies  about  the  nineteenth  year,  is  usually  involved  when  the  primary 
lesion  is  in  the  bone.  This  may  cause  a  separation  of  the  epiphysis,  or 
it  may  arrest  the  growth  of  the  bone  at  this  end  and  thus  lead  to  a  short- 
ening of  the  limb,  unless  compensated  by  increased  growth  at  the  lower 
cud,  where  the  principal  increase  in  length  occurs. 

The  well-known  fact  that  patients  with  hip  disease  often  complain 
of  pain  in  the  knee,  in  excess  of  or  to  the  exclusion  of  pain  in  the  hip, 
is  readily  explained  as  a  reflex.    Thus  both  hip  joint  and  knee  joint  are 


500        '  ~    -"  THE  LOWER  EXTREMITY 

supplied  by  filaments  from  the  obturator,  anterior  crural,  and  sciatic 
nerves,  and  the  irritation  of  the  hip-joint  filaments  is  referred  to  those 
of  the  knee. 

Dislocation  of  the  Hip. — The  comparative  rarity  of  this  injury  is  due 
to  the  great  strength  of  the  joint.  In  spite  of  the  tremendous  leverage 
of  the  long  femur,  it  forms  less  than  2  per  cent,  of  all  dislocations.  A 
considerable  proportion  (nearly  50  per  cent.,  Prahl)  occur  before  the 
age  of  twenty.  The  traumatic  dislocations  may  be  practically  divided 
into  (1)  the  backward,  including  (a)  the  ischiatic  and  (b)  that  onto  the 
dorsum  ilii,  and  (2)  the  forward  or  inward,  including  (a)  the  obturator 
and  (b)  the  iliopectineal  and  pubic.  The  backward  dislocations  are 
by  far  the  most  common.  The  prerequisites  for  a  dislocation  are  rupture 
of  the  capsule,  almost  always  of  the  ligamentum  teres,  and,  to  a  less  ex- 
tent, of  the  cotyloid  ligament.  Naturally  the  thinner  and  weaker  parts 
of  the  capsule  are  those  generally  torn;  the  iliofemoral  band  is  almost 
never  torn,  a  fact  of  the  utmost  importance,  which  is  due  to  its  strength 
and  the  fact  that  it  is  relaxed  when  the  luxation  is  produced.  The 
position  of  the  limb  in  which  (backward)  dislocation  most  often  occurs 
is  that  of  flexion,  adduction,  and  inward  rotation.  In  this  position  the 
head  of  the  bone  presses  upon  the  thin  postero-inferior  part  of  the  cap- 
sule. When  violence  is  received  in  this  position,  approximating  the 
knee  and  the  pelvis,  as  in  a  fall  from  a  height  or  the  fall  of  a  heavy  object 
upon  the  back,  this  part  of  the  capsule  tears  and  allows  the  head  to 
be  dislocated  downward  over  the  lower  and  least  prominent  portion  of 
the  cotyloid  rim.  The  primary  displacement  is  therefore  downward. 
The  secondary  displacement  is  such  as  may  be  allowed  by  the  intact 
portion  of  the  capsule,  and  especially  the  iliofemoral  band,  which  is 
now  rendered  tense.  The  attachment  of  the  latter  ligament  to  the  femur 
forms  a  new  centre  of  motion,  or  the  fulcrum  of  a  lever  of  which  the  head 
and  neck  are  the  short  arm  and  the  rest  of  the  femur  the  long  arm; 
The  capsule  is  either  primarily  torn  at  different  parts  in  the  different 
varieties  or  secondarily  torn  in  different  directions  from  the  primary 
tear,  to  allow  the  different  forms  to  occur  from  a  primary  downward 
displacement.  Thus  in  obturator  dislocations  the  capsule  is  torn  on 
the  inner  and  lower  side,  in  the  iliopectineal  form  antero-internally, 
while  the  everted  dorsal  dislocation  depends  upon  a  tear  of  the  outer 
branch  of  the  Y  ligament. 

If  the  thigh  be  partly  lowered  (extended),  while  the  adduction  and 
inward  rotation  remain  unchanged,  the  head  glides  up  behind  the  ace- 
tabulum to  a  dorsal  or  backward  position.  If,  on  the  other  hand,  the 
thigh  is  abducted  or  rotated  out  as  it  is  lowered,  the  head  and  neck, 
moving  on  the  new  centre  of  motion,  are  forced  in  the  opposite  direc- 
tion to  the  shaft  and  are  displaced  inward  and  forward.  This  is  exempli- 
fied in  the  reduction  of  dislocations.  When  there  is  a  backward  disloca- 
tion the  head  of  the  bone  is  brought  below  the  acetabulum  by  increasing 
the  flexion,  and  it  may  readily  be  converted  into  an  inward  dislocation 
by  too  much  abduction  or  outward  rotation,  especially  if  upward  (for- 
ward) traction  on  the  thigh  is  omitted.     In  the  reduction  of  an  obturator 


THE   HIP  JOINT  501 

dislocation  Bigelow  gives  preference  to  converting-  it  into  the  dorsal  form 
by  the  reverse  of  the  above  process. 

Dorsal  or  Backward  Dislocations. — In  dorsal  or  backward  dislocations 
the  head  of  the  bone  lies  behind  or  behind  and  above  the  centre  of 
the  acetabulum,  either  just  behind  the  latter  and  in  front  of  the  spine  of 
the  ischium,  (a)  ischiatic  form,  or  higher  up  on  the  ilium,  (b)  dislocation 
onto  the  dorsum  ilii,  as  high  up  as  in  front  of,  but  seldom  above,  the  apex 
of  the  great  sciatic  notch.  In  the  recumbent  position  the  latter  lies 
directly  behind  the  anterior  superior  iliac  spine.  The  head  can  be 
obscurely  felt  in  the  buttocks,  above  the  tuber  ischii,  beneath  the  gluteus 
maximus.  The  great  trochanter  is  rotated  forward  and  approaches 
Dearer  the  iliac  crest  than  normally.  It  lies  from  2  to  3  cm.  (|  to  lj  in.), 
above  Nelaton's  line  in  the  ischiatic  form,  and  from  3  to  7  cm.  (1^  to 
2|  in.)  in  the  iliac  form.  The  real  shortening  varies  within  these  limits; 
the  measured  shortening  is  increased  by  the  flexion  present,  but  may 
be  decreased  or  even  wholly  lacking  by  reason  of  the  adduction;  the 
apparent  shortening  is  increased  by  the  flexion  and  adduction.  The  head 
may  pass  above  or  below  the  obturator  internus  tendon.  Although 
Bigelow  classed  all  cases  in  which  the  head  was  below  the  tendon  as 
ischiatic  and  all  above  as  iliac,  many  if  not  most  of  those  called  iliac 
pass  below  and  beneath  the  tendon.  The  flexion  and  inversion  are 
greater  when  the  head  lies  below  the  obturator  tendon.  The  higher  up 
the  head  rests,  the  farther  up  on  the  postero-external  aspect  is  the  capsule 
torn.  Usually  the  quadratus  femoris  and  sometimes  the  obturator 
internus  and  even  the  pyriformis  tendons  are  torn.  The  limb  is  held 
somewhat  flexed,  adducted  and  rotated  in.  This  position  can  be  readily 
exaggerated,  but  the  attempt  to  give  it  the  opposite  position  is  resisted. 
The  tension  of  the  iliofemoral  band  and  of  the  iliopsoas  muscle  and  the 
position  of  the  head  and  neck,  which  must  accommodate  themselves  to 
the  plane  on  which  they  lie,  are  largely  responsible  for  the  position  as- 
sumed and  the  resistance  to  movement  in  the  opposite  direction.  The 
normal  depression  behind  the  trochanter  is  lost  and  the  depressibility 
of  the  soft  parts  below  the  outer  half  of  Poupart's  ligament,  where  the 
head  normally  lies,  is  increased. 

Inward  or  Forward  Dislocations. — If  after  the  primary  displacement 
the  thigh  is  abducted  the  head  of  the  bone  may  pass  inward  and  forward 
from  below  the  acetabulum,  along  its  inner  edge,  until  it  reaches  the 
thyroid  foramen,  (a)  thyroid  form,  or,  if  the  limb  is  further  extended  and 
everted,  it.  may  pass  forward  and  come  to  lie  upon  or  near  the  iliopubic 
eminence,  <bj  iliopectineal  form,  or,  more  rarely,  nearer  the  symphysis,  (c) 
pubic  form.  While  this  mode  of  production  may  occur  in  a  number  of 
,  i Ik-  obturator  form  is  most,  often  due  to  violence  received  on  the 

back  of  (lie  hij)  while  the  limb  is  Hexed  and  abducted,  and  the  iliopec- 

tineal  form  to  hyperextension  while  the  limb  is  everted.  In  both  forms 
the  head  can  be  distinguished  by  touch  or  even  by  sight  in  its  new  posi- 
tion, especially  in  the  pubic  variety.  In  the  latter  varieties  the  femoral 
artery  can  be  fell  pulsating  directly  over  it,  m  its  inner  or  its  outer  side 
(pubic  form).    The  great  trochanter  is  displaced   inward   toward  the 


502  THE  LOWER  EXTREMITY 

acetabulum,  over  which  it  may  be  felt.  The  outer  and  posterior  portions 
of  the  hip  are  flattened.  Both  the  obturator  and  anterior  crural  nerves 
have  suffered  from  pressure.  The  posture  of  the  limb  varies.  In  the 
thyroid  variety  it  is  flexed,  abducted,  and  usually  rotated  out.  There  is 
apparent  lengthening  by  reason  of  the  tilting  of  the  pelvis,  to  bring  the 
abducted  limb  into  line.  The  measurement  may  show  lengthening  on 
account  of  the  downward  position  of  the  head,  in  spite  of  the  shortening 
due  to  abduction.  In  some  cases  the  head  has  passed  over  the  ramus  into 
the  perineum  (perineal  form).  In  the  iliopectineal  variety  the  limb  is  but 
little  if  at  all  abducted,  markedly  everted,  and  but  little  if  at  all  flexed.  In 
this  form  the  apparent  lengthening  of  the  thyroid  form  may  be  wanting, 
if  there  is  no  abduction,  and  there  is  measured  and  actual  shortening. 
From  its  position  (eversion)  and  the  presence  of  shortening  it  may  be 
mistaken  for  fracture  of  the  neck  of  the  femur,  but  it  can  be  distinguished 
from  it  by  the  presence  of  the  head  in  its  new  position,  the  depression 
and  inward  displacement  of  the  trochanter,  and  the  marked  flattening  of 
the  outer  aspect  of  the  hip.  In  the  pubic  form  the  thigh  is  abducted, 
everted,  and  flexed,  and  the  vessels  lie  externally. 

In  the  reduction  of  dislocations  of  the  hip  we  may  lay  down  the  general 
rule  that  the  head  should  be  made  to  take,  in  the  reverse  direction,  the 
route  it  took  in  becoming  dislocated.  The  chief  obstacle  to  reduction 
is  the  tension  of  the  Y  ligament  in  the  partly  extended  position,  and 
to  overcome  this  the  thigh  is  first  flexed.  This  flexion  also  brings  the 
head  down  to  the  lower  part  of  the  socket,  where  it  escaped.  As  a  general 
rule  we  may  direct  to  first  (1)  increase  the  deformity  and  then  (2)  make 
the  opposite  movements  with  forward  traction.  (1)  Relaxes  the  Y  liga- 
ment, releases  the  head  and  brings  it  below  the  socket,  while  (2)  forces 
the  head  through  the  tear  in  the  capsule  into  the  acetabulum.  It  is 
virtually  a  circumduction  with  forward  traction.  In  the  dorsal  form 
increasing  at  first  the  adduction  and  inversion  lifts  the  head  of  the 
femur  away  from  the  pelvis  and  the  projecting  rim  of  the  acetabu- 
lum. Unless  we  make  forward  traction,  after  flexing  and  otherwise 
increasing  the  deformity,  a  backward  dislocation  is  likely  to  be  con- 
verted into  a  forward  one,  and  vice  versa  by  the  "opposite  movements." 
In  other  words,  the  reduction  is  to  be  made  largely  by  traction  rather  than 
by  manipulation.  The  spasmodic  contraction  of  the  muscles  opposes 
this  forward  traction,  hence  the  value  of  anesthesia.  Stimson's  method, 
in  backward  dislocations,  of  placing  the  patient  on  the  face  with  the 
flexed  thigh  hanging  over  the  end  of  the  table  enables  us  to  dispense  with 
anesthesia,  as  a  rule;  for  the  weight  of  the  limb,  tiring  out  and  overcoming 
the  contraction  of  the  muscles,  serves  instead  of  traction,  so  that  a  slight 
rocking  of  the  flexed  limb  accomplishes  the  reduction.  The  obturator 
form  may  be  reduced  by  first  converting  it  into  the  backward  form  by 
increasing  the  deformity  and  then  making  the  opposite  movements 
without  traction.  The  obturator  form  may  also  be  reduced  by  increasing 
the  deformity  and  then  making  the  opposite  movements  with  traction 
forward,  avoiding  too  free  inward  rotation,  for  fear  of  producing  a 
backward  dislocation;  or  it  may  be  reduced  by  flexion,  traction,  and 


THE  HIP  JOINT  503 

outward  rotation  (Kocher).  The  iliopectineal  form  is  best  reduced  by 
flexion,  traction,  and  inward  rotation.  The  rule  to  increase  the  deform- 
ity, i.  e.,  the  extension,  etc.,  should  not  be  followed  here.  It  may  be 
convenient  to  remember  that  the  internal  condyle  looks  nearly  in  the 
same  direction  as  the  head  of  the  femur. 

Congenital  Dislocations  of  the  Hip. — The  hip  on  one  or  both  sides 
may  be  congenitally  dislocated  from  lack  of  development  of  the  acetab- 
ulum, especially  its  upper  or  iliac  portion.  In  congenital  dislocations 
the  capsule  is  stretched  and  thickened,  the  neck  is  short,  and  the  head 
is  flat  and  rests  on  the  dorsum  of  the  ilium,  when  the  child  walks.  If 
reduced,  there  is  nothing  to  keep  it  from  slipping  out  again.  The  tro- 
chanters can  be  seen  beneath  the  glutei,  above  Nelaton's  line,  and  there 
is  usually  lordosis  of  the  lumbar  spine  to  compensate  for  the  backward 
displacement  of  the  centre  of  gravity.  When  long  displaced  the  muscles 
become  shortened  so  that  the  head  cannot  be  reduced  without  dividing 
or  stretching  them.  A  new  socket  may  form  on  the  ilium  from  osteo- 
phyte outgrowths.  The  ligamentum  teres  is  usually  stretched  and  not 
torn. 

Fractures  of  the  Neck  of  the  Femur. — The  long  axis  of  the  neck 
measures  3.5  to  4  cm.  (If  to  If  in.),  its  vertical  diameter  averages  36  mm. 
(1^-  in.),  its  anteroposterior  25  mm.  (1  in.)  The  latter  diameter  is  much 
less  than  that  of  the  great  trochanter,  and  these  two  parts  are  so  joined 
that  a  considerable  part  of  the  trochanter  extends  behind  the  posterior 
surface  of  the  neck.  In  falls  on  the  feet  the  neck  transmits  the  weight 
of  the  body  in  such  a  manner  as  to  receive  a  cross-strain,  favoring  fracture, 
on  account  of  the  angle  which  it  forms  with  the  shaft,  averaging  125 
degrees  in  the  adult.  This  angle  is  greater  in  the  infant,  but  does  not 
decrease  after  adult  life  is  reached.  Hence  the  theory  that  the  frequency 
of  fractures  of  the  neck  of  the  femur  in  old  age  depends  upon  a  decrease 
of  this  angle  to  one  nearer  a  right  angle,  a  position  that  would  favor  frac- 
ture, is  not  sustained  by  facts  and  has  been  abandoned.  Nor  is  the  angle 
sufficiently  less  or  the  trochanter  enough  more  prominent  in  those  of 
small  stature  and  in  the  average  female  to  account  for  the  more  frequent 
occurrence  of  this  injury  in  that  sex  (two  and  a  half  times  more  frequent 
than  in  men,  over  fifty). 

The  fact  remains,  however,  that  this  fracture  is  essentially  a  lesion  of 
old  age,  is  more  common  in  women  than  in  men,  and  is  often  the  result 
of  slight  causes,  a  stumble,  a  misstep,  or  a  slight  fall.  These  facts  in- 
dicate  the  existence  of  senile  changes  as  a  predisposing  cause,  and  it  is 
found  that  all  parts  of  the  bone  are  much  rarefied  and  the  cortical  sub- 
itance  is  much  thinner  in  the  aged.  These  changes  begin  and  advance 
most,  quickly  in  the  femoral  neck  (Humphry).  This  osteoporosis 
affects  the  cortex  of  the  under  and  forepart  of  the  neck,  in  the  line 
of  greatest  pressure,  and  also  two  plates  of  compact  bone  which 
ngthen  the  neck,  (1)  the  calcar  jemorale,  a  nearly  vertical  plate 
projecting  into  the  .spongy  substance,  toward  the  great  trochanter, 
from  a  little  in  front  of  the  small  trochanter,  and  (2)  a  thin  dense 
plate,  continuous  with  the  posterior  surface  of  the  neck,  which   extends 


504  THE  LOWER  EXTREMITY 

in  the  spongy  tissue  toward  the  outer  surface  of  the  shaft  and  of  the 
trochanter. 

As  the  capsule  is  attached  in  front  to  the  base  of  the  neck  (the  inter- 
trochanteric line)  and  behind  12  mm.  (^  in.)  or  more  internal  to  the 
posterior  intertrochanteric  line,  it  follows  that  there  can  be  no  strictly 
extracapsular  fractures  of  the  neck,  for  the  latter  is  entirely  intracapsular 
in  front.  A  more  scientific  classification  of  these  fractures  than  that  into 
intracapsular  and  extracapsular  is  the  division  into  (a)  fractures  through 
the  neck  and  (6)  fractures  at  the  base  of  the  neck. 

(a)  Fractures  through  the  Neck. — Fractures  through  the  neck  may  occur 
at  any  point  between  the  junction  of  the  head  and  neck  and  the  base  of 
the  latter,  though  they  are  said  to  be  more  common  near  the  head.  It  is 
this  variety  especially  that  occurs  from  slight  violence  in  the  aged.  As 
a  rule,  there  is  angular  displacement  at  the  fracture,  from  the  crushing 
of  the  bone  or  the  penetration  of  one  fragment  into  the  other  posteriorly 
and  inferiorly,  so  that  the  neck  is  bent  at  an  angle  directed  upward  and 
forward.  This  causes  eversion  and  adduction  of  the  thigh,  elevation  of 
the  trochanter,  and  decrease  of  the  angle  of  the  neck.  If  the  fracture  is 
near  the  head  the  latter  may  be  penetrated  by  the  smaller  and  more 
compact  neck,  but  true  impaction  is  rare.  The  thick  periosteum  is 
usually  untorn  over  a  portion  of  the  circumference  of  the  neck,  especially 
along  its  upper  part,  where  it  is  very  vascular.  The  periosteum  is  rein- 
forced by  fibers  reflected  from  the  femoral  attachment  of  the  capsule 
toward  the  head  in  three  bands  or  retinacula,  one  behind  and  one  at 
either  end  of  the  anterior  intertrochanteric  line.  The  untorn  portion  of 
the  periosteum  not  only  holds  the  fragments  together,  but  furnishes  a 
source  of  blood  supply  to  the  smaller  fragment,  to  assist  in  the  process 
of  repair.  The  only  other  source  of  blood  supply  of  the  head,  after 
fracture,  is  the  ligamentum  teres.  Movements  that  may  tear  the  untorn 
portion  of  the  periosteum  are  to  be  carefully  avoided  in  diagnosis  and 
treatment.  Hence  crepitus  should  not  be  sought  for  by  rotation  or 
longitudinal  movements. 

(6)  Fractures  at  the  Base  of  the  Neck. — Fractures  at  the  base  of  the  neck 
usually  follow  the  line  of  junction  of  the  neck  and  shaft  quite  closely, 
but  other  lines  of  fracture  traverse  the  great  trochanter,  as  a  rule.  The 
neck  is,  as  a  rule,  bent  backward  by  the  crushing  of  its  posterior  and 
more  fragile  part,  or  by  its  penetration  into  the  trochanter  posteriorly. 
In  this  latter  way  the  trochanter  may  be  split  into  two  or  many  pieces. 
According  to  Stimson  true  impaction,  or  penetration  with  fixation,  is 
the  exception,  but  it  is  more  common  than  in  fractures  through  the  neck. 
In  this  form  the  cause  is  usually  a  fall  on  the  trochanter.  The  violence 
is  greater  than  in  the  preceding  form.  This  form  includes  most  of  those 
cases  where  fracture  occurs  before  old  age.  According  to  Whitman,  it 
is  more  common  in  childhood,  and  it  is  also  found  to  be  more  common 
in  early  and  middle  adult  life  than  was  formerly  supposed.  The  axis 
of  the  neck  and  of  the  great  trochanter  are  not  in  the  same  plane,  but 
meet  in  an  angle,  open  posteriorly,  at  the  anterior  trochanteric  line.  In 
a  fall  on  the  trochanter  this  angle  is  exaggerated  and  the  bone  gives  way 


THE  HIP  JOINT  505 

here  at  its  weakest  and  most  spongy  portion.  By  this  mechanism  the 
fragments  tend  to  be  separated  in  front  and  driven  together  behind, 
causing  penetration  posteriorly,  angular  deformity  of  the  neck,  and  out- 
ward rotation  (eversion)  of  the  thigh. 

The  essential  point  in  the  functional  prognosis,  and  the  reason  for 
attempting  to  distinguish  between  these  two  forms,  lies  in  the  vitality  and 
power  of  repair  of  the  upper  fragment.  This  depends  not  so  much  upon 
impaction  or  the  situation  of  the  fracture  as  upon  the  preservation  of 
the  blood  supply,  which  runs  toward  the  head  in  the  thick  cervical 
periosteum.  These  vessels  are  not  much  injured  in  fractures  at  the  base 
of  the  neck,  and  in  those  through  its  narrow  part  we  have  seen  that 
enough  of  the  periosteum  is  usually  untorn  to  preserve  the  vitality  of 
the  fragment.  The  number  of  specimens  of  undoubted  bony  union 
after  fracture  of  the  narrow  part  of  the  neck  is  sufficiently  large  not 
only  to  demonstrate  its  possibility,  but  to  indicate  that  it  is  probably 
common  enough,  with  proper  treatment,  to  justify  the  attempt  to  obtain 
it  whenever  possible. 

Symptoms  and  Signs.— "The  symptoms  and  signs  of  fracture  of  the  neck 
of  the  femur,  upon  which  the  diagnosis  depends,  are  (1)  interference  with 
function,  (2)  localized  pain  on  movement,  (3)  position  of  the  limb, 
(4)  crepitus,  in  a  few  cases,  (5)  enlargement  or  widening  of  the  great 
trochanter  from  comminution,  especially  in  fractures  at  the  base  of  the 
neck,  and  from  infiltration  of  the  overlying  soft  parts,  (6)  elevation  of 
the  trochanter  and  its  approach  to  the  median  line,  (7)  swelling  and 
diminished  depressibility  of  the  region  below  the  outer  half  of  Poupart's 
ligament.  In  addition  to  these  the  cause  of  the  injury  is  important, 
especially  if  it  be  trifling  and  in  an  aged  person.  As  to  the  posture,  the 
injured  limb  is  almost  always  everted,  slightly  flexed,  abducted,  and  it 
may  appear  shortened.  The  eversion  is  largely  the  effect  of  gravity 
in  connection  with  the  diminished  activity  of  the  muscles;  it  also 
depends  upon  the  angular  displacement  from  crushing  and  penetration 
posteriorly,  with  or  without  impaction.  In  addition  the  upward  dis- 
placement relaxes  the  internal  rotator  muscles  more  than  the  external, 
so  that  the  former  can  act  only  at  great  disadvantage.  It  is  well  to  bear 
in  mind  that  eversion  and  loss  of  function  may  be  due  to  a  simple  con- 
tusion. Exceptionally  inversion  is  present  instead.  Shortening  is  due 
(1)  to  over-riding  and  (2)  to  alteration  of  the  angle  of  the  neck,  from 
Crushing  or  penetration  interiorly;  it  varies  from  'J.  to  0  em.  (|  to  2\  in.), 
ft  is  usually  greater  in  fractures  at  the  base  of  the  neek.  In  those  through 
the  narrow  part  of  the  neek  it  may  be  slight  or  even  wanting  at  first, 
and  increases  gradually,  or  sometimes  suddenly,  after  a  few  hours  or  days. 
Adiglit  primary  shortening  and  its  subsequent  gradual  increase  is  thought 
by  many  to  be  pathognomonic  of  fractures  through  the  neek.  The  short- 
ening also  causes  a  broadening  and  thickening  of  the  upper  part,  of  the 

thigh.     Allis  has  called  attention  to  the  relaxation  of  the  fascia  lata 

between  the  cresl  of  the  ilium  and  the  great  trochanter  as  a  result  of  the 
elevation  of  the  trochanter.  Rotation  of  the  trochanter  upon  a  shorter 
radius  than  normal,  in  rotation  of  the  thigh,  is  a  theoretical  rather  than 
a  practical  sign. 


506  THE  LOWER  EXTREMITY 

An  exact  diagnosis  in  all  cases  between  "intracapsular"  and  "extra- 
capsular" fractures  is  both  impossible  and  useless.  Some  cases  of  frac- 
ture at  the  base  of  the  neck  (extracapsular)  can  be  positively  recognized 
by  the  splitting,  broadening,  and  sensitiveness  to  pressure  of  the  trochanter 
and  by  the  immediate  and  considerable  shortening.  Likewise,  slight 
violence,  advanced  age,  great  disability,  and  slight  shortening  point  to 
fracture  through  the  narrow  part  of  the  neck. 

Treatment. — In  general  the  treatment  should  aim  to  secure  union, 
by  means  of  fixation  and  traction.  The  full  restoration  of  form  and 
function  is  not  often  to  be  expected.  Fairly  good  function  is  not  un- 
commonly present  after  such  injuries,  even  without  bony  union.  Bony 
union  is  almost  always  accompanied  by  some  deformity,  shortening, 
eversion,  and  adduction,  owing  to  the  angle  in  the  neck  which  points 
upward  and  forward,  due  to  the  crushing  and  impaction  below  and 
behind.  The  adduction  prevents  the  compensatory  abduction  which 
would  overcome  the  shortening,  hence  the  patient  limps.  This  may 
be  largely  obviated  by  treating  the  fracture  by  traction  in  the  abducted 
position.  In  those  not  too  old  or  infirm  a  still  -better  result  may  be  ob- 
tained by  the  method  advocated  by  Whitman  of  first  reducing  the  shorten- 
ing and  the  angular  deformity  of  the  neck  by  traction  in  inversion  and 
extreme  abduction  and  maintaining  extension  in  this  position  by  a  plaster 
spica. 

Excessive  violence  that  may  tear  the  untorn  portion  of  the  periosteum 
of  the  neck  should  be  strictly  avoided;  but  traction  in  abduction  produces 
no  cross-strain,  but  is  in  line  with  this  periosteum  and  has  little  tendency 
to  tear  it,  unless  the  traction  is  very  excessive. 

Separation  of  the  epiphysis,  whose  conjugal  cartilage  adjoins  the 
head,  and  is  entirely  intracapsular,  has  been  demonstrated  by  specimens 
in  a  few  cases,  but  it  is  even  rarer  than  fracture  of  the  neck  at  the  corre- 
sponding age,  i.  e.,  before  nineteen,  when  bony  union  occurs  (see  p.  499). 

The  great  trochanter  is  formed  as  a  separate  epiphysis,  which  in  a 
few  cases  has  been  observed  to  be  separated  from  the  shaft,  sometimes 
as  the  result  of  osteomyelitis.     Bony  union  occurs  in  the  eighteenth  year. 

Coxa  vara  is  an  affection  of  adolescence,  usually  rachitic  in  origin. 
Under  the  weight  of  the  body  the  neck  yields,  its  angle  with  the  shaft 
is  reduced  to  90  degrees  or  less,  the  limb  is  shortened,  and  the  trochanter 
is  elevated  and  made  more  prominent.  Hence  it  may  be  mistaken  for 
hip  disease  or  congenital  dislocation  of  the  hip. 

Excision  of  the  head  of  the  femur  is  sometimes  called  for  in  hip  disease. 
The  chief  anatomical  interest  in  the  operation  concerns  the  method  of 
reaching  the  deeply  placed  joint.  An  external  incision  (Langenbeck's 
operation)  has  been  much  employed.  With  the  thigh  flexed  at  an  angle 
of  45  degrees  and  rotated  a  little  inward,  an  incision  of  10  to  11  cm.  (4  to 
4|-  in.)  is  made  in  the  long  axis  of  the  limb,  so  that  one-third  of  the  in- 
cision is  over  the  great  trochanter,  a  little  behind  its  centre,  the  remaining 
two-thirds  over  the  ilium,  reaching  up  to  the  top  of  the  great  sciatic  notch. 
In  the  position  in  which  the  limb  is  placed  the  incision  would  meet  the 
posterior  superior  spine,  if  prolonged.     The  gluteal  muscles  are  split  in 


PLATE  XLIX 


FIG.  171 


Hip  Joint.      Anteroposterior  strongly    rotated    outward.      Male, 
aged  twenty-four  years. 

1,  border  of  acetabulum;  2,  neck  of  femur;  -i,  apex  of  greal  trochanter. 


THE  HIP  JOINT  507 

line  with  their  fibers,  and  the  capsule  is  opened  in  the  same  line,  and  also 
transversely  near  the  acetabulum.  By  cutting  the  cotyloid  ligament  air  is 
admitted  behind  the  head,  thereby  equalizing  the  atmospheric  pressure  on 
its  two  sides,  so  that  it  is  readily  separated  from  the  acetabulum.  This 
same  procedure  is  carried  out  in  exarticulation  at  the  hip  joint,  but  in  the 
latter  operation  the  ligamentum  teres  requires  division,  while  in  excisions 
it  has  usually  disappeared  as  a  result  of  the  lesion  for  which  the  operation 
is  required.  Among  the  disadvantages  of  the  external  incision  is  the 
fact  that  many  large  and  important  muscles  and  many  of  the  arteries 
that  meet  about  the  great  trochanter  are  split  or  divided. 

The  method  of  anterior  incision  of»Hueter,  Parker,  or  Barker  is  an  excel- 
lent one  anatomically  and  practically.  This  is  carried  downward  from 
12  mm.  Q  in.)  below  the  anterior  superior  iliac  spine;  the  tensor  vaginae 
femoris  and  the  glutei  muscles  are  retracted  outward  and  the  sartorius 
and  rectus  inward,  exposing  the  capsule.  No  muscles  and  no  vessels  or 
nerves  of  any  importance  are  divided. 

Amputation  or  exarticulation  of  the  thigh  at  the  hip  joint  is  performed 
by  various  methods.  The  control  of  hemorrhage  is  the  essential  feature 
of  the  operation  and  may  be  accomplished  in  several  ways:  (1)  The 
femoral  artery  may  be  ligated  before  the  flaps  are  cut,  or  while  they  are 
being  formed,  as  in  the  "  anterior- racket"  incision.  (2)  The  femoral 
may  be  compressed  in  the  flap  by  the  fingers  of  an  assistant,  just  before 
the  vessels  are  cut.  The  fingers  are  introduced  behind  the  vessels, 
which  are  compressed  between  them  and  the  thumb,  which  is  on  the 
surface.  These  methods  do  not  control  the  bleeding  from  the  branches 
of  the  internal  iliac.  Hence  (3)  pressure  on  the  lower  end  of  the  aorta 
by  Lister's  tourniquet  has  been  used  and  also  (4)  pressure  on  the  common 
iliac  against  the  pelvic  brim  by  Davy's  lever  introduced  into  the  rectum. 
Both  3  and  4  have  been  generally  abandoned.  (5)  Pressure  on  the 
common  iliac  by  the  Angers  of  an  assistant  introduced  through  an  inter- 
muscular- incision  in  the  iliac  region  (McBurney)  I  have  found  very 
serviceable.  <lj  The  elastic  tourniquet  around  the  upper  end  of  the 
limb,  with  or  without  the  use  of  long  needles,  or  skewers,  thrust  through 
the  upper  cud  of  the  thigh,  to  prevent  the  rubber  tubing  or  bandage 
from  slipping  down,  is  the  method  most  generally  used.  In  order  to 
control  the  gluteal  and  sciatic  vessels  the  tourniquet  must  be  carried 
internal  to  the  tuber  isehii,  so  as  to  compress  them  as  they  emerge  from 
thegreai  sacrosciatic  foramen.  By  passing  over  the  groin  it  compresses 
the  femoral  vessels,  and  by  being  carried  above  the  iliac  crest  it  is  pre- 
vented from  slipping  downward. 

The  varieties  of  incision  are  numerous.  We  may  make  an  "external 
i"  or  oval  incision,  with  the  summit  5  cm.  (2  in.)  above  the  tro- 
chanter; an  "anterior-racket"  incision,  with  the  centre  at  the  middle  of 
Poupart's  ligament;  or  a  circular  amputation  of  the  thigh  combined 
with  an  external  vertical  incision  extending  up  5  cm.  (2  in.)  above  the 
trochanter,  etc.  The  various  incisions  have  their  own  advantages,  and 
di  advantages.  The  vessels  divided  are  the  femoral,  profunda,  gluteal, 
idatic,  and   branches  of  tin    external  and  internal  circumflex,  and  the 


508  THE  LOWER  EXTREMITY 

long  saphenous  vein.  Their  position  at  the  point  of  section  varies  with 
the  form  and  length  of  the  flaps.  In  those  methods  with  long  flaps 
the  branches  of  the  gluteal  and  sciatic  arteries  are  small  and  unimpor- 
tant. In  the  "anterior-racket"  incision  no  tourniquet  or  compression 
is  used,  the  vessels  are  tied  as  they  are  met  with,  as  in  removing  a  tumor, 
and  very  little  blood  need  be  lost.  The  muscles  attached  to  the  great 
trochanter  and  the  upper  end  of  the  shaft  are  divided  close  to  the  bone; 
the  other  muscles,  sartorius,  rectus,  adductors,  gracilis  and  hamstring 
muscles,  are  divided  at  varying  levels. 


THE  THIGH. 

Limits. — Under  this  term  is  included  the  region  lying  below  the 
regions  last  described,  i.  e.,  below  the  level  of  the  gluteal  fold,  and 
above  the  subcrural  bursa  at  the  knee,  i.  e.,  a  line  5  to  8  cm.  (2  to  3^  in.) 
above  the  patella.  It  is  more  or  less  conical  in  shape,  and  slightly 
curved  with  its  convexity  in  front  and  externally.  On  cross-section  it 
is  round  in  the  female,  by  reason  of  the  subcutaneous  fat,  triangular 
in  the  male,  with  its  base  behind.  The  thigh  is  directed  obliquely 
downward  and  inward,  the  inward  obliquity  being  more  marked  in  the 
female,  on  account  of  the  wider  separation  of  the  acetabula,  and  also  in 
those  of  short  stature,  on  account  of  the  shortness  of  the  femora. 

Surface  Markings  and  Landmarks. — The  rectus  muscle  forms  a  promi- 
nence in  front,  most  noticeable  when  the  muscle  is  in  action,  in  flexion 
of  the  hip  or  extension  of  the  knee.  On  either  side  of  this  prominence, 
and  most  conspicuous  in  the  lower  half  of  the  thigh,  is  a  slight  eminence 
formed  by  the  vasti  muscles,  the  inner  one  being  the  more  marked. 
Along  the  inner  aspect  of  the  thigh,  from  the  apex  of  Scarpa's  triangle 
downward,  is  a  groove  indicating  the  interval  between  the  adductors 
and  the  quadriceps  femoris.  In  this  groove  lie  the  femoral  vessels  and, 
more  superficially,  the  sartorius  muscle.  The  outer  surface  of  the  thigh 
is  flattened  or  slightly  depressed  by  the  iliotibial  band  of  the  fascia  lata. 
At  the  junction  of  the  external  and  posterior  aspects  of  the  thigh  the 
position  of  the  external  intermuscular  septum,  corresponding  to  the 
interval  between  the  hamstring  muscles  and  the  vastus  externus,  is 
indicated  by  a  slight  depression,  and  is  perceptible  to  palpation.  The 
bone  cannot  be  plainly  palpated. 

Topography. — The  line  of  the  femoral  vessels  (see  p.  490)  and  of  the 
sciatic  nerve  (see  p.  487)  have  already  been  given.  The  long  saphenous 
vein  follows  the  course  of  the  inner  border  of  the  sartorius  muscle  in  a 
line  from  the  saphenous  opening  (see  p.  490)  to  the  posterior  border  of 
the  muscle  at  the  level  of  the  internal  condyle.  It  is  not  infrequently 
double  in  the  thigh.  The  long  saphenous  nerve  follows  the  femoral 
artery,  crossing  to  its  inner  side,  in  front  of  the  artery,  in  Hunter's 
canal.  Emerging  through  the  anterior  wall  of  this  canal,  it  passes 
under  cover  of  the  sartorius  in  the  lower  fourth  of  the  thigh,  and  lies 
to  the  inner  side  of  the  knee. 


PLATE  L 


FIG.   172 


VASTUS    EXT 
MUSCLE 


FASCIA     LATA — * 


EXT.    INTERMUS- 
CULAR   SEPT 


l)     RECTUS-FEMO- 
RIS    MUSCLE 
K|£Z   VASTUS    INT. 

'/^Jr)  \jj>  '^r"  muscle 

«n&\  •  V':\V~>^'SARTOR'US    M' 
^^"W\\>ife^"'^^FEMORAL    ART. 

iPHE- 

I    VEIN 

iPHE- 

NERVE 

DUCTOR 

INGUS   M. 

EP   FEMO- 

»AL    ART. 

ADDUCTOR 

MAGNUS 

MUSCLE 


SEMITENDI- 

NOSUS    MUS. 


GREAT    SCIATIC  POST.    INTERMUS- 

NERVE  CULAR    SEPTUM 


Cross-section  of  the  Middle  or  the  Right  Thigh.     Upper  segment 
of  the  section.     (Tillaux.) 


THE  THIGH  509 

The  Skin. — The  skin  of  the  thigh  is  coarse  on  the  outer  side,  thin  and 
fine  internally,  and  is  often  used  in  skin  grafting.  Its  loose  attachment  to 
the  deep  fascia  fa  rors  the  performance  of  circular  amputations,  as  no  dis- 
section of  a  skin  flap  is  required,  merely  the  upward  retraction  by  an 
assistant.  Along  the  line  of  the  external  intermuscular  septum  it  is 
a  little  more  adherent,  and  may  require  freeing  with  the  knife.  The 
laxity  of  the  subcutaneous  tissue,  which  contains  a  very  variable  quantity 
of  fat,  allows  the  stripping  up  of  large  flaps  of  skin  or  the  formation  of 
extensive  extravasations  beneath  it,  in  case  of  injury.  The  long  saphe- 
nous vein  is  contained  in  this  subcutaneous  tissue. 

The  Fascia  Lata. — The  fascia  lata  resists  and  directs  the  extension 
of  tumors,  abscesses,  and  deep  extravasations  of  blood,  especially  on  the 
outer  aspect  of  the  thigh,  where  it  is  stronger.  Through  rents  or  cuts  in 
the  fascia  lata  the  underlying  muscle  has  occasionally  bulged  and  been 
caught,  forming  a  so-called  hernia  of  the  muscle.  The  quadriceps  and 
adductor  longus  have  been  thus  herniated.  From  the  deep  surface  of 
the  fascia  two  fibrous  septa  pass  inward  to  the  two  lips  of  the  linea  aspera 
and  divide  the  thigh  into  an  anterior  and  a  posterior  compartment.  This 
division  has  little  surgical  importance.  The  internal  intermuscular  septum 
separates  the  vastus  internus  from  the  adductors,  and  is  very  thin  and 
unimportant.  The  external  separates  the  vastus  externus  from  the  ham- 
string muscles.  According  to  Tillaux,  another  septum,  extending  from 
the  fascia  lata,  at  the  junction  of  its  inner  and  posterior  aspects,  outward 
to  the  external  intermuscular  septum,  separates  the  adductor  from  the 
hamstring  group  of  muscles  (Fig.  172). 

The  Femoral  Artery. — The  femoral  artery  may  be  ligated  at  any 
part  of  its  course,  which  has  already  been  given  (see  p.  490).  The 
"place  of  election"  is  at  the  apex  of  Scarpa's  triangle.  It  may  also  be 
ligated  at  the  base  of  the  triangle  (common  femoral)  or  in  Hunter's  canal. 
The  latter  lies  at  the  lower  end  of  the  middle  third  of  the  thigh,  beneath 
the  sartorius  muscle,  which  is  retracted  internally  to  reach  it.  It  measures 
5  to  6  cm.  (2  to  2o-  in.)  in  length,  and  is  bounded  by  the  adductor  longus  be- 
hind, the  vastus  internus  externally,  and  in  front  by  a  firm  membranous 
layer  of  oblique  tendinous  fibers  passing  from  the  adductors  longus  and 
magnus  downward  and  outward  to  the  vastus  internus.  The  vein  here 
lies  behind  and  somewhat  external  to  the  artery,  quite  closely  con- 
nected with  it,  and  an  extra  vena  comes  may  lie  in  front  of  the  artery 
and  complicate  its  ligation.  The  long  saphenous  nerve  lies  in  the  canal, 
in  front  and  slightly  external  to  the  sheath  of  the  vessels.  Within  the 
canal  it  crosses  in  front,  of  the  vessels,  which  it  accompanies  to  the 
opening  in  the  adductor  magnus,  where  it  perforates  the  canal  and 
passes  beneath  the  sartorius.  The  vastus  internus  separates  the  artery 
from  the  femur,  so  that  in  compression  of  the  artery,  which  must  be 
made  from  within  outward,  there  is  no  firm  bed  against  which  to  com- 
press it.  In  rare  instances  the  femoral  artery  is  replaced  by  two  trunks. 
It  is  occasionally  ligated  for  popliteal  aneurysm  or  for  wounds. 

The  Great  Sciatic  Nerve.  The  great  sciatic  nerve  usually  divides 
into  the  internal  and  external  popliteal  nerves  about  the  middle  of  the 


510  THE  LOWER  EXTREMITY 

thigh,  and  its  internal  popliteal  branch  continues  the  direction  of  the 
trunk;  not  infrequently  it  bifurcates  higher  up,  even  within  the  pelvis, 
and  occasionally  lower  down.  Below  the  lower  border  of  the  gluteus 
maximus  it  is  quite  superficial,  and  a  little  lower  is  crossed  by  the  biceps. 
At  the  middle  of  the  thigh  it  lies  between  the  biceps  behind  and  the  adduc- 
tor magnus  in  front,  beneath  or  anterior  to  the  thin  fascial  layer  separating 
the  hamstring  and  adductor  muscles.  Lower  down  it  lies  between  the 
hamstring  muscles  which  are  internal  and  external  to  it.  It  is  surrounded 
by  a  layer  of  loose  connective  tissue  and  fat,  continued  downward  from 
the  pelvis.  This  tissue  affords  a  favorable  pathway  for  the  sinking  of 
abscesses  from  the  pelvis,  even  to  the  lower  thigh  or  the  popliteal 
space.  The  place  of  election  for  opening  deep  abscesses  of  the  thigh 
or  the  removal  of  sequestra  from  the  femur  is  the  external  surface, 
for  here  the  bone  is  not  very  deep  and  there  are  no  important  vessels 
or  nerves. 

Fractures  of  the  Femur. — The  shaft  of  the  femur  may  be  frac- 
tured at  any  part,  but  most  commonly  in  the  middle  third,  which  is 
affected  by  the  leverage  of  both  ends.  The  fracture  is  usually  oblique, 
but  may  be  transverse,  especially  in  children  and  in  direct  fractures, 
which  are  most  common  in  the  lower  half.  Fractures  in  the  upper 
half  are  almost  always  oblique.  The  obliquity  usually  corresponds 
to  the  normal  curvature  of  the  bone.  Thus  it  commonly  runs  from 
behind  forward  and  downward  in  the  middle  third,  forward  and  out- 
ward in  the  upper  third.  The  displacement  is  marked  and  is  the  re- 
sult of  the  fracturing  violence,  the  contraction  of  the  thigh  muscles,  and 
the  swelling  beneath  the  firm  fascia  lata,  by  reason  of  which  the  thigh 
is  necessarily  shortened  at  the  same  time  that  it  is  broadened  by  the 
swelling.  In  addition  there  is  an  angular  displacement,  usually  directed 
forward,  or  forward  and  outward,  in  the  direction  of  the  natural  curve, 
and  attributed  to  the  contraction  of  the  adductor  muscles,  which  form  the 
chord  of  the  arc  of  the  curve.  The  lower  fragment  may  also  be  rotated 
out  by  gravity.  In  fractures  of  the  upper  third  the  usual  forward  and 
outward  displacement  of  the  lower  end  of  the  upper  fragment  is  largely 
due  to  muscular  action.  (1)  The  adductors  and  hamstring  muscles 
draw  the  lower  fragment  up  and  in,  behind  the  upper  fragment,  and  tilt 
the  latter  forward  and  outward,  or  according  to  the  obliquity  of  the  frac- 
ture. (2)  The  psoas  and  gluteal  muscles  also  draw  the  upper  fragment 
forward  and  outward.  The  sharp  ends  of  an  oblique  fracture,  especially 
the  lower  end  of  the  upper  fragment,  may  be  driven  into  and  caught  in 
the  surrounding  muscles,  which,  being  interposed  between  the  fragments, 
prevent  reduction  of  the  deformity  and  lead  to  delayed  union  or  non- 
union. The  artery  or  vein  are  rarely  torn  or  compressed  by  the  fragments, 
an  injury  leading  to  gangrene.  I  have  seen  one  such  case  in  the  lower 
third,  where  the  danger  of  this  complication  is  greatest.  In  fractures 
in  the  lower  third  the  lower  fragment  may  be  tilted  backward,  probably 
by  the  action  of  the  gastrocnemius.  This  tilting  is  the  most  difficult 
element  of  the  deformity  to  reduce  and  keep  reduced.  It  necessitates 
flexion  at  the  hip  and  knee  to  relax  the  muscles  concerned,  and  con- 


THE  REGION  OF  THE  KNEE  511 

tinued  flexion  of  the  knee  to  relax  the  gastrocnemius  and  prevent  recur- 
rence of  the  displacement. 

Except  in  rare  cases  of  transverse  or  incomplete  fractures,  the  limb  is 
always  shortened.  This  shortening  may  vary  from  0.5  to  10  or  even  15  cm. 
(|  to  4  or  even  6  in.),  and  is  due  to  the  over-riding  and  the  angular 
displacement  of  the  fragments.  A  principal  object  of  treatment  is  the  over- 
corn  ing  of  th is  shortening  by  continued  extension.  Practically  union  never 
occurs  without  slight  shortening,  though  the  possibility  of  union  without 
shortening  may  be  admitted.  The  average  amount  of  shortening  after 
union  is  18  mm.  (f  in.),  though  3.5  cm.  (1£  in.)  of  shortening  may  occur 
without  a  limp  in  the  gait,  the  shortening  being  compensated  by  the 
tilting  of  the  pelvis.  In  this  connection  it  may  be  noted  that  the  lower 
limbs  are  usually  of  unequal  length,  the  inequality  averaging  6  mm. 
(\  in.),  the  left  being  the  longer,  as  a  rule  (Wight).  In  only  about  10  per 
cent,  of  cases  are  they  of  equal  length,  so  that  using  one  limb  as  a  stand- 
ard of  length  for  the  other  is  inaccurate,  if  the  difference  in  length  is 
trifling.  In  the  treatment  of  fractures  of  the  upper  third  the  entire  limb 
should  be  flexed  and  abducted  to  coincide  with  the  forward  and  outward 
tilting  of  the  upper  fragment.  In  transverse  fractures  with  over-riding 
this  displacement  must  be  corrected  so  that  the  ends  may  come  in  apposi- 
tion. To  allow  this  replacement  anesthesia  should  be  given  to  cause 
complete  muscular  relaxation,  without  which  reduction  can  hardly  be 
accomplished  by  traction. 

In  amputation  at  or  below  the  mifldle  of  the  thigh  the  circular  method 
is  easy  and  gives  good  results.  The  ease  of  retraction  of  the  skin  flap 
has  been  referred  to,  and  the  thigh  is  seldom  so  conical  as  to  require  the 
splitting  of  this  flap.  The  muscles  retract  unevenly,  those  attached  to 
the  femur  retracting  but  little,  those  not  so  attached,  the  free  muscles 
(sartorius,  rectus,  gracilis,  and  hamstring  muscles),  retracting  consider- 
ably. Hence  the  stump  is  retracted  and  the  muscles  are  divided  a  second 
or  even  a  third  time. 


THE  REGION  OF  THE  KNEE. 

Limits. — This  includes  the  region  between  the  level  of  the  tubercle 
of  the  tibia  and  the  level  of  the  upper  end  of  the  subcrural  bursa,  3  to  4 
fingers'  breadth  or  5  to  8  cm.  (2  to  3\  in.)  above  the  patella. 

Landmarks  and  Surface  Markings. — (1)  Anterolateral  Region. — 
The  patella  is  plainly  seen  and  felt  in  front,  its  inner  border  being 
somewhat  tin-  more  prominent.  In  the  extended  position  of  the  limb 
the  patella  can  be  moved  to  ;md  fro,  when  the  quadriceps  is  relaxed,  but 
is  drawn  up  and  firmly  fixed  against  the  femur  when  the  muscle  is  con- 
tacted. When  tin-  knee  is  flexed  the  patella  occupies  the  hollow 
-n  the  two  bones,  and  is  not  so  readily  palpated.  In  this  position 
v.'   can  fed,  above  the  patella  mid  through  the  quadriceps  expansion, 

th<-  trochlear  m/rface  of  the  femur,  especially  its  prominent  outer  border. 
A   line   from    'he   upper  angle  of  this   border   to   the  adductor  tubercle 


512 


THE  LOWER  EXTREMITY 


marks  the  level  of  the  epiphyseal  line.  The  adductor  tubercle  is  felt  at 
the  upper  end  of  the  internal  condyle  posteriorly.  It  is  directly  above 
the  epiphyseal  line  and  is  the  favorite  situation  for  exostoses  in  adolescence. 
The  internal  condyle  and  its  tuberosity  are  more  prominent  than  the  outer, 
but  the  outer  tuberosity  of  the  tibia  is  more  prominent  than  the  inner. 
The  tubercle  of  the  tibia  is  plainly  felt  at  the  upper  end  of  the  anterior 
tibial  border,  and  at  the  lower  end  of  the  ligamentum  patellae.  About 
on  a  level  with  the  tubercle,  the  head  of  the  fibula  is  felt  on  the  postero- 
external aspect,  1  cm.  (-|  in.)  below  the  joint  line. 


FATTY  TISSUE 
BENEATH    LOWER 
END   OF    PATEL 


Fig.  173 
patella       prepatellar  bursa 


INTERNAL 

LATERAL 

LIGAMENT 


POSTERIOR 

CRUCIAL 

LIGAMENT 


SARTORIUS 
MUSCLE 


EXTERNAL  LATERA' 
LIGAMENT 


NTERIOR  CRUCIAL 
LIGAMENT 


EXTERNAL    POPLITEAL 
NERVE 


GRACILIS 
MUSCLE 
SEMIMEMBRA 

NOSUS  muscle'semitendi' 

WITH    BURSA  NOSUS 

MUSCLE 


GASTROC- 
NEMIUS 
TIBIAL  MUSCLE 

VE!N      NERVE 


GASTROC- 
NEMIUS 
MUSCLE 


Cross-section  of  the  right  knee  joint,  seen  from  above. 


In  the  semiflexed  position  of  the  knee,  when  the  quadriceps  muscle 
is  contracted,  the  ligamentum  patellae  can  be  plainly  felt,  and  often  seen, 
as  a  ridge  extending  from  the  apex  or  lower  end  of  the  patella  to  the 
tubercle  of  the  tibia.  In  this  position  there  is  a  slight  groove  on  either 
side  of  the  tendon,  but  in  the  extended  position,  when  the  quadriceps 
is  relaxed,  the  grooves  are  not  marked.  In  stout  subjects  the  grooves 
may  be  obliterated  by  fat,  which  in  all  cases  is  found  most  abundantly 
behind  the  upper  half  of  the  tendon,  separating  it  from  the  synovial 
cavity.  The  ligamentum  patellae  lies  in  the  axis  of  the  leg,  and  hence 
forms  a  slight  obtuse  angle  with  the  direction  of  the  quadriceps,  which 
lies  in  the  axis  of  the  thigh.  On  either  side  of  the  patella  is  a  slight  groove, 
which  is  obliterated  by  effusion  into  the  joint  and  may  be  filled  with  fat 
in  the  obese.     In  stout  subjects  the  patella  may  appear  to  He  in  the 


THE  REGION  OF  THE  KNEE  513 

bottom  of  a  groove  instead  of  on  a  ridge.  Above  the  patella  is  a  depres- 
sion which  is  converted  into  a  prominence  in  case  of  effusion  into  the 
joint.  On  both  sides,  but  particularly  on  the  inner  side,  the  interarticular 
line  between  the  tibia  and  femur  can  be  felt  as  a  slight  depression  in 
normal  conditions.  When  the  knee  is  extended  this  line  is  just  above 
the  level  of  the  apex  of  the  patella,  which  serves  as  a  convenient  land- 
mark to  it.  It  is  here  that  one  feels  for  a  displaced  semilunar  cartilage. 
The  iliotibial  band  of  the  fascia  lata,  descending  between  the  patella 
and  the  back  of  the  external  condyle  to  the  external  tuberosity  of  the 
tibia,  may  be  felt  as  a  rounded  band,  most  distinctly  when  the  joint  is 
forcibly  extended.  Its  insertion  is  about  midway  between  the  apex  of  the 
patella  and  the  head  of  the  fibula. 

Posterior  or  Popliteal  Region. — In  this  region  the  landmarks  are  best 
felt  when  the  knee  is  slightly  flexed.  In  this  position  the  concavity  of 
the  space  appears,  while  in  the  extended  position  it  is  flat  or  bulging. 
At  the  outer  side,  behind  the  iliotibial  band,  the  tendon  of  the  biceps  is 
felt  descending  to  the  head  of  the  fibula.  Directly  in  front  of  the  tendon 
the  upper  part  of  the  external  lateral  ligament  is  palpable  in  slight  flexion, 
and  close  to  the  inner  border  of  the  tendon,  posteriorly,  the  external 
popliteal  or  peroneal  nerve  is  readily  felt  as  a  rounded  cord.  In  its 
descent  the  nerve  crosses  the  neck  of  the  fibula,  where  it  may  be  rolled 
under  the  finger,  before  it  enters  the  peroneus  longus.  The  internal 
popliteal  nerve  may  be  felt  and,  in  thin  subjects,  even  seen  descending 
vertically  in  the  middle  of  the  space.  On  the  inner  side  from  without 
inward  we  can  feel  the  long,  slender,  and  more  superficial  tendon  of  the 
semitendinosus,  more  deeply  and  less  distinctly  the  thicker  and  less  promi- 
nent tendon  of  the  semimembranosus  and  the  gracilis.  The  last  two 
appear  as  one  tendon,  but  by  a  little  manipulation  we  can  insinuate  the 
finger  between  them.  The  popliteal  lymph  nodes  when  normal  cannot 
be  felt.  At  the  lower  end  of  the  space  we  can  feel  the  converging  fleshy 
heads  of  the  gastrocnemius.  In  the  flexed  position  a  crease  in  the  shin 
crosses  this  space  some  distance  above  the  joint  line.  It  disappears  in 
(■■.tension. 

Topography. — The  popliteal  artery,  passing  through  the  opening  in 
the  adductor  magnus,  enters  the  popliteal  space  beneath  (anterior  to) 
the  semimembranosus,  a  little  to  the  inner  side  of  the  middle  line, 
and  thence  runs  in  a  line  to  the  'interval  between  the  two  heads  of 
the  gastrocnemius  at  the  centre  of  the  lower  end  of  the  space.  It 
ads  al  first  obliquely  outward,  reaches  the  middle  line  opposite  the 
joint,  and  thence  runs  vertically.  It  bifurcates  on  a  level  with  the 
tubercle  of  the  tibia.  It  lies  against  the  back  of  the  femur,  the  pos- 
terior  ligament  of  the  knee,  and  the  popliteus  muscle,  and  can  be  com- 
pressed against  the  femur  in  (he  upper  partof  the~space,  where  also  its 
pulsations  can  be  felt.  The  popliteal  vein  lies  behind  or  superficial  to  it, 
to  H  outer  side  above,  bul  it  crosses  to  its  inner  side  below.  The  internal 
popliteal  nerve  descends  in  Hi*'  middle  line,  continuing  fli<-  course  of  the 
great  sciatic,  and  i;  superficial  to  the  vein,  by  which  it  is  separated 
from  the  artery, 


514  THE  LOWER  EXTREMITY 

The  superior  articular  arteries  run  transversely  just  above  the  con- 
dyles of  the  femur;  the  inferior  articular  arteries  are  just  above  the 
head  of  the  fibula  externally,  and  a  little  below  the  internal  tuberosity 
of  the  tibia  internally.  The  deep  branch  of  the  anastomotica  magna 
descends  in  front  of  the  adductor  magnus  to  the  internal  condyle,  the 
superficial  branch  runs  with  the  internal  saphenous  nerve.  The  short 
saphenous  vein  perforates  the  deep  fascia  at  the  lower  part  of  the  pop- 
liteal space  in  the  middle  line.  It  is  not  visible,  as  a  rule,  unless  vari- 
cose, and  it  has  been  suggested  (Herapat)  that  varices  of  this  vein  may 
depend  upon  a  narrowness  of  the  opening  in  the  fascia.  The  long 
saphenous  vein  passes  along  the  back  of  the  internal  condyle,  above 
which  it  lies  along  the  posterior  border  of  the  sartorius.  It  is  joined 
by  the  internal  saphenous  nerve  just  below  the  joint  line. 

Soft  Parts  in  Front  of  the  Knee. — The  skin  is  thick  and  very  movable, 
thus  protecting  the  joint  from  injuries  or  diminishing  their  gravity,  and 
permitting  incisions  into  the  joint  to  be  very  indirect  or  valvular,  which 
some  advise  in  the  removal  of  loose  bodies  in  the  joint.  The  deep 
fascia,  continuous  with  the  fascia  lata,  is  attached  to  the  two  tuberosities 
and  the  tubercle  of  the  tibia,  and  strengthens  the  joint  on  either  side  of 
the  patella.  This  part  of  the  joint  is  also  strengthened  by  the  lateral 
expansions  of  the  quadriceps  tendon,  which  are  connected  with  the  sides 
of  the  patella  and  the  ligamentum  patellae  anteriorly  and  reach  as  far  as 
the  lateral  ligaments  posteriorly.  Hence  they  are  called  lateral  patellar 
ligaments.  In  fractures  of  the  patella,  where  there  is  any  considerable 
separation  of  the  fragments,  there  is  always  more  or  less  of  a  tear  in  the 
lateral  expansion  on  either  side  of  the  line  of  fracture. 

There  are  two  bursse  in  this  region  that  require  mention:  (1)  The 
prepatellar  bursa  lies  in  front  of  the  lower  two-thirds  of  the  patella  and 
the  upper  end  of  the  ligamentum  patellae.  It  does  not  reach  the  internal 
border,  but  often  projects  over  the  external  border  of  the  patella. 
Although  it  is  often  described  as  separating  the  patella  from  the  skin, 
it  lies,  according  to  Tillaux,  beneath  the  deep  fascia.  Others  (Gruber, 
Joessel,  etc.)  describe  bursse  in  three  situations,  beneath  (1)  the  skin, 
(2)  the  superficial  fascia,  and  (3)  the  deep  fascia,  of  which  the  last, is  the 
most  constant.  When  more  than  one  is  enlarged,  they  are  separated 
wholly  or  partly  by  septa  which  easily  yield  to  inflammatory  changes, 
so  that  in  opening  a  purulent  prepatellar  bursitis  a  single  cavity  is  often 
found.  The  bursa  is  often  enlarged  and  not  infrequently  inflamed  in 
those  who  kneel  much,  such  as  housemaids,  etc.,  hence  prepatellar 
bursitis  is  commonly  known  as  "housemaids'  knee."  Suppurative 
bursitis  may  lead  to  caries  of  the  patella,  from  which  the  bursa  is  sepa- 
rated only  by  the  periosteum.  I  have  several  times  met  with  tuberculous 
inflammation  of  this  bursa.  (2)  The  small  bursa  between  the  patellar 
ligament  and  the  tubercle  of  the  tibia  is  separated  from  the  synovial  cavit) 
by  a  pad  of  fat  lying  behind  the  upper  end  of  the  ligament.  It  does  not 
communicate  with  the  joint  and  is  not  often  enlarged  or  inflamed, 
indistinct  feeling  of  fluctuation  on  either  side  of  the  upper  end  of  th( 
patellar  ligament  is  often  due  to  the  loose  fat  beneath  it  and  not  to  ai 


PLATE  LI 


FIG.  174 


SEMIMEMBRANOSUS 
MUSCLE 


Tl 


COMMUN 
NERVE 
EXTERNA 
SAPHENOUS 

VEII 


XTERNAL    POPLIT- 
EAL   NERVE 
ETERNAL    POPLIT- 
EAL   NERVE 
POPLITEAL    ARTERY 
POPLITEAL   VEIN 


ON.     COMMUNIC 
NERVE 


ON.     LONGUS 
MUSCLE 


Popliteal  Region  of  the  Right  Side.     (Joessel.) 


THE  REGION  OF  THE  KNEE  515 

enlargement  of  this  bursa.     This  fat  often  protrudes  a  little  on  either 
side  of  the  ligament,  and  thus  still  further  simulates  an  enlarged  bursa. 

Soft  Parts  at  the  Back  of  the  Knee. — The  soft  parts  at  the  back  of 
the  knee  either  bound  or  are  contained  in  the  popliteal  space.  The 
skin  covering  it  is  not  so  movable  as  in  front,  and  the  contraction  of  a 
cicatrix  resulting  from  burns,  ulcerations,  or  injury  may  result  in  a  bent 
knee.  In  straightening  a  knee,  long  ankylosed  in  the  flexed  position, 
the  skin  at  the  back  is  liable  to  be  torn.  The  deep  fascia,  continuous 
with  the  fascia  lata  above,  has  no  bony  attachments  here.  Its  firmness 
limits  the  extension  toward  the  surface  of  popliteal  tumors  or  abscesses. 
Hence,  being  pent  up  in  the  popliteal  space,  they  cause  severe  pain  and 
tend  to  spread  down  into  the  leg  or  up  into  the  thigh.  From  the  latter 
region  abscesses  may  extend  to  the  popliteal  space  through  the  opening 
for  the  femoral  vessels  in  the  adductor  magnus,  or  they  may  follow  the 
great  sciatic  nerve  from  the  thigh,  the  buttocks,  or  the  pelvis. 

The  Muscles. — The  muscles  which  bound  the  space,  and  give  it  a 
lozenge  shape,  are  the  biceps  above  and  externally,  the  semitendinosus 
and  semimembranosus  above  and  internally,  and  the  two  heads  of  the 
gastrocnemius  below  and  on  either  side.  The  upper  muscles,  known 
as  the  hamstring  muscles,  are  the  cause  of  flexion  of  the  knee  in  knee-joint 
disease,  from  the  irritation  of  articular  filaments  of  the  sciatic  nerve, 
motor  branches  of  which  supply  these  muscles.  Continued  flexion  in 
this  disease  leads  to  a  'partial  backward  luxation  of  the  tibia  and  to  the 
contracture  and  shortening  of  these  muscles.  According  to  Tillaux,  the 
biceps  and  semitendinosus  are  frequently  shortened  in  these  conditions, 
the  semimembranosus  rarely  so.  The  shortened  tendons  require 
tenotomy  prior  to  straightening  the  knee.  In  tenotomy  of  the  biceps 
the  relation  of  the  external  popliteal  nerve  just  internal  to  it  is  to  be  borne 
in  mind.  Contraction  or  contracture  of  the  muscle  renders  the  tendon 
more  superficial  and  increases  its  distance  from  the  nerve.  To  diminish 
the  risk  of  cutting  the  nerve  the  tendon  should  be  cut  from  within  out- 
ward about  3  cm.  (\\  in.)  above  the  head  of  the  fibula.  The  ham- 
string tendons,  especially  the  biceps,  may  be  ruptured  by  violence  in  the 
position  of  extreme  flexion  of  the  hip  while  the  knee  remains  extended, 
8  position  in  which  (hey  are  greatly  stretched. 

The  Popliteal  Vessels. — The  popliteal  vessels  lie  deeply  and  are 
well  protected,  hence  they  are  seldom  wounded.  The  artery,  however, 
i-  more  often  (he  seat  of  aneurysm  than  any  other,  with  the  exception  of 
the  thoracic  aorta.  Many  factors  have  been  adduced  to  account  for 
this  d  is  posit  inn.  (])  It  divides  into  two  large  vessels,  which  increases 
the  blood  pressure  above  the  bifurcation.  (2)  It  is  supported  by  the 
lax  tissue  of  the  popliteal  space  and  not  by  muscles.  (3)  Its  course  is 
curved,  in  the  flexed  position,  like  the  thoracic  aorta,  so  that  the  pressure 
i  unequally  distributed  (4)  It  is  subjected  to  the  strain  of  frequent 
and  extensive  movements.  Thus  forced  flexion  of  the  knee  diminishes 
or  arrests  the  flow  of*  blood  below  and  increases  the  pressure  above  the 
angle  in  the  artery.  When  the  artery  is  the  seat  of  an  aneurysm,  (he 
pres  lire  exerted  by  forced  flexion  of  the  knee  stops  the  circulation,  and 


516  THE  LOWER  EXTMEMITY 

popliteal  aneurysms  have  been  successfully  treated  in  this  way.  Extreme 
extension  of  the  knee  may  so  stretch  the  artery,  which  is  said  to  be  un- 
usually liable  to  atheromatous  changes,  that  the  inner  and  middle  coats 
may  become  thinned  or  ruptured.  The  relations  of  the  artery  to  the  vein 
and  the  internal  popliteal  nerve  explain  the  edema  of  the  leg  and  the 
nerve  symptoms  due  to  the  pressure  of  an  aneurysm  on  these  structures. 
The  close  relations  of  the  artery  to  the  posterior  ligament,  on  which  it 
lies,  explains  the  occasional  penetration  of  an  aneurysm  into  the  joint. 
In  straightening  the  bent  knee  in  cases  of  chronic  knee-joint  disease  the 
artery  may  be  ruptured.  In  this  respect  cuneiform  resection  of  the  knee 
is  a  safer  operation  than  forcible  straightening.  The  artery  is  more 
closely  connected  with  the  posterior  ligament  below  than  above  the  joint 
line,  hence  Tillaux  recommends  sawing  the  tibia  from  behind  forward  in 
resection  of  the  knee  to  avoid  accidental  wound  of  the  artery,  but  this 
is  not  necessary  with  ordinary  care.  A  backward  luxation  of  the  tibia 
has  occasionally  been  complicated  by  rupture  of  the  artery.  Anomalies 
of  the  artery  are  rare  and  consist  mainly  in  a  high  division. 

The  popliteal  vein  is  so  closely  adherent  to  the  artery  that  some  difficulty 
may  be  found  in  separating  the  two  in  ligature  of  the  latter.  In  spite  of 
its  more  superficial  position  than  the  artery,  the  vein  is  ruptured  by  vio- 
lence even  less  often  than  the  artery,  and,  according  to  Treves,  never 
alone.  This  may  be  owing  to  the  circumstance,  noted  by  Tillaux,  that 
it  is  so  thick  that  it  does  not  collapse  on  section,  and  thus  resembles  an 
artery  so  closely  that  it  may  readily  be  mistaken  for  it  in  operations 
on  the  cadaver. 

The  lymph  nodes  of  the  popliteal  space  consist  of  four  or  more  small 
nodes,  one  just  beneath  the  fascia  and  below  the  opening  for  the  short 
saphenous  vein,  the  others  situated  more  deeply  along  the  popliteal  vessels. 
They  are  rarely  swollen,  and,  when  involved,  form  a  median  tumor 
unlike  those  derived  from  the  bursae. 

Bursas. — The  bursse  at  the  back  of  the  knee  are  situated  on  either 
side,  two  on  the  inner  and  four  on  the  outer  side.  Many  of  these  are 
not  constant  and  are  unimportant  on  account  of  the  fact  that  they  never 
communicate  with  the  joint  and  are  seldom  enlarged. 

(1)  Between  the  internal  condyle  and  the  inner  head  of  the  gastroc- 
nemius, and  extending  between  the  latter  and  the  semimembranosus,  is 
the  largest  bursa  of  this  region  and  the  one  most  often  inflamed.  It  com- 
municates with  the  joint  in  fully  50  per  cent,  of  cases  (Gruber),  and 
more  often  in  adults  and  in  robust  subjects.  Its  slit-like  opening  into 
the  joint  may  become  closed  by  the  tightening  of  the  posterior  liga- 
ment in  extension,  which  may  explain  its  firm  feeling  in  extension,  in 
contrast  with  its  more  flabby  feeling  in  flexion.  In  the  latter  position 
it  may  sometimes  entirely  disappear  on  pressure.  It  may  become 
enlarged  in  effusions  into  the  joint,  or  independently.  (2)  A  small 
inconstant  bursa,  between  the  semimembranosus  and  the  internal 
tuberosity  of  the  tibia,  may  communicate  with  (1),  but  never  directly 
with  the  joint.  On  the  outer  side  there  is  (3)  a  bursa  between  the  popliteus 
tendon   and   the  external  lateral  ligament,   without  joint  connection 


THE  REGION  OF  THE  KNEE  517 

except  occasionally,  and  (4)  one  between  the  same  tendon  and  the 
external  tibial  tuberosity.  This  bursa  is  strictly  a  diverticulum  from 
the  joint  and,  by  occasionally  communicating  with  the  upper  tibiofibular 
joint  (in  about  14  per  cent,  of  cases,  Gruber),  connects  the  latter  with 
the  knee  joint.  (5)  A  bursa  between  the  outer  head  of  the  gastroc- 
nemius and  the  external  condyle  is  neither  constant  nor  connected  with 
the  joint.  (6)  One  between  the  biceps  and  the  external  lateral  ligament 
is  more  constant,  but  is  also  not  connected  with  the  joint.  It  is  closely 
related  to  the  peroneal  nerve.  Tumors  due  to  a  bursitis  are  situated 
laterally  and  usually  internally,  because  (1)  is  most  often  enlarged, 
but  median  cysts  may  occur  in  the  popliteal  space,  due  to  the  hernial 
protrusion  of  the  synovial  membrane  through  small  openings  in  the  pos- 
terior ligament.  Bursitis  may  cause  stiffness  of  the  joint  and  pain  on 
extension.  It  may  be  distinguished  from  aneurysm  by  its  lateral  position, 
its  lack  of  expansile  pulsation,  and  the  fact  that  compression  of  the  femoral 
does  not  affect  its  size. 

The  Knee  Joint. — The  knee  joint  owes  its  strength  to  that  of  the 
ligaments,  tendons,  and  fasciae  which  join  together  and  surround  its  com- 
ponent parts.  By  reason  of  its  strength  and  the  large  extent  of  its  oppos- 
ing surfaces,  traumatic  dislocation  is  uncommon  in  spite  of  its  exposure 
to  injury,  and  only  occurs  from  severe  violence.  The  most  common 
form  is  dislocation  of  the  tibia  forward  by  direct  violence  or  by  hyper- 
extension;  the  next  commonest  is  dislocation  of  the  tibia  backward. 
The  lesion  is  a  grave  one  because  of  the  great  violence  required  and  the 
frequency  of  compounding  and  of  injury  of  the  popliteal  vessels. 

\Vhen  the  femur  is  held  vertically  the  plane  of  the  lower  surfaces  of 
the  two  condyles  is  not  horizontal,  as  is  that  of  the  upper  surfaces  of  the 
tibia,  but  the  longer  inner  condyle  projects  lower  than  the  outer.  Hence 
to  make  the  joint  surfaces  parallel  the  lower  end  of  the  femur  must  be 
inclined  inward,  the  position  it  normally  occupies  in  the  body.  It  forms 
an  angle  with  the  tibia  of  about  172  degrees,  opening  outward.  [  Another 
result  of  this  inclination  is  to  bring  the  knees  together,  although  the  hips 
are  widely  separated,  and,  as  the  tibia  descends  nearly  vertically,  the 
ankles  are  also  in  contact.  In  the  normal  erect  position  the  line  of 
gravity  descends  through  the  external  condyle  and  tuberosity. 

In  the  condition  known  as  knock-knee  or  genu  valgum  the  knee  is 
unusually  prominent  internally.  This  condition  is  usually  bilateral. 
It  is  due  to  ;i  downwind  projection  of  the  internal  condyle,  due  to  an 
inward  bending  of  the  lower  end  of  the  diaphysis  of  the  femur,  causing 
an  obliquity  of  the  epiphyseal  line  (Mikulicz).  Jn  most  cases  there  is 
a  similar,  slighter,  upward  prominence  of  the  internal  tuberosity  of  the 
tibia.  In  addition,  there  Is  contraction  of  the  biceps,  the  capsule,  and  the 
ligaments  on  the  outer  side  and  relaxation  of  the  ligaments  on  the  inner 
side.  The  usual  cause  is  rickets,  in  which  the  distortion  of  the  bones  is 
commonly  the  primary  factor,  and  the  deformity  occurs  most  often 
between  the  ages  of  two  and  four  years.  But  it  may  occur  in  adolescents 
or  from  any  injury  or  disease  thai  weakens  or  relaxes  the  ligamentous 
icturej  on  the  inner  aspect  of  the  joint.      In  adolescents,  etc.,  the 


518  THE  LOWER  EXTREMITY 

weakness  of  the  supporting  muscles  causes  the  assumption  of  the  "atti- 
tude of  rest/'  with  the  feet  separated  and  everted.  This  transfers  the 
strain  of  standing  from  the  muscles  to  the  ligaments  and  causes  a  stretch- 
ing and  elongation  of  the  internal  lateral  ligament.  The  normal  pressure 
thus  removed  from  the  growing  bones  on  the  inner  side  by  their  slight 
separation  there  follows  an  overgrowth  of  the  diaphyses,  on  this  side, 
beyond  the  epiphyseal  lines  of  both  bones,  especially  of  the  femur. 
The  increase  of  pressure  on  the  outer  side  results  in  atrophy  of  the 
bones,  contraction  and  shortening  of  the  external  lateral  ligament,  of 
the  iliotibial  band,  and  of  the  biceps  tendon,  which  further  increase  the 
deformity.  The  prominence  of  the  internal  condyle  is  readily  recognized 
when  the  knee  is  sharply  flexed.  It  is  a  curious  fact  that  the  deformity, 
however  great,  disappears  completely  when  the  knees  are  flexed.  This  is 
because  the  deformity  is  due  to  the  downward  projection  of  the  internal 
condyle,  so  that  the  axis  of  the  hinge  motion  is  not  transverse  but  inclined 
outward  and  upward,  bringing  the  feet  away  from  one  another  when  the 
knees  are  extended,  but  together  when  they  are  flexed.  It  may  also  be 
due  to  the  outward  rotation  of  the  femur  that  accompanies  the  flexion. 

Besides  the  characteristic  deformity  of  knock-knee,  the  tibia  is  apt  to 
be  rotated  outward,  the  femur  inward,  and  flat-foot  (talipes  valgus) 
is  likely  to  result.  It  may  also  be  a  cause  of  genu  valgum.  In  walking 
the  knees  "interfere,"  and  in  extreme  cases  there  is  a  swaying  movement 
from  side  to  side  to  allow  the  knees  to  pass  one  another.  Knock-knee, 
when  well  established,  is  treated  by  osteotomy  of  the  femur  above  the 
condyles,  with  or  without  the  removal  of  a  wedge  of  bone  (cuneiform 
osteotomy),  and  then  by  straightening  the  limb.  In  Macewen's  oper- 
ation, the  one  usually  practised,  the  femur  is  divided  from  the  inner  side, 
transversely  to  its  long  axis,  in  a  line  12  mm.  (^  in.)  above  the  top  of 
the  external  condyle.  This  is  above  the  epiphyseal  line,  the  synovial 
membrane,  and  the  superior  articular  vessels;  below  and  in  front  of  the 
anastomotica  magna. 

Ligaments. — In  the  semiflexed  position  of  the  joint  most  of  the  liga- 
ments are  relaxed,  a  condition  that  favors  the  backward  displacement 
of  the  tibia  by  the  contracture  of  the  hamstring  muscles,  in  chronic 
knee-joint  disease  with  flexion.  Owing  to  the  relaxation  of  the  ligaments 
in  this  position  rotary  and  slight  lateral  motion  of  the  knee  is  allowed 
in  semiflexion.  Hence  if  we  wish  to  test  the  knee  for  abnormal  lateral 
mobility,  such  as  is  due  to  rupture  of  the  lateral  ligaments,  etc.,  the 
test  should  be  made  when  the  knee  is  extended.  All  except  the  anterior 
ligaments  are  taut  in  extension,  only  the  posterior  crucial  and  the  anterior 
ligaments  are  taut  in  extreme  flexion.  The  powerful  crucial  ligaments 
are  not  relaxed  in  any  position  of  the  joint.  The  anterior  crucial  not 
only  resists  hyper  extension  and  anterior  displacement  of  the  tibia, 
but  also  rotation  of  the  leg  inward.  The  posterior  crucial  ligament 
resists  forced  flexion  and  posterior  displacement  of  the  tibia.  The  lateral 
ligaments  lie  behind  the  centre  of  the  joint,  about  the  junction  of  its 
middle  and  posterior  thirds,  hence  they  are  taut  in  extension,  relaxed  in 
flexion.     In  the  latter  position  they  resist  outward  rotation  of  the  tibia. 


PLATE  LII 


FIG.    175 


Left  Knee  Joint.     Knee  slightly  flexed.     Internal  condyle  on  the 
plate.     Male,  aged  twenty-eight  years. 

1,  external  condyle;  2,  internal  condyle;  •'{,  external  tuberosity  <>f  tibia;   i.  internal 

i  uberoeil  v  of  t  il>i.-i 


THE  REGION  OE  THE  KNEE  519 

They  are  not  very  strong.  If  pus  within  the  joint  escapes  into  the  pop- 
liteal space  it  usually  does  so  through  the  thinnest  part  of  the  posterior 
ligament,  the  part  below  the  oblique  ligament  of  Winslow. 

When  one  is  in  the  act  of  falling  backward,  or  in  any  direction  with 
the  knees  bent,  an  instinctive  effort  is  made  to  avoid  the  fall  by  violently 
contracting  the  quadriceps  to  straighten  the  knee.  By  such  a  spasmodic 
contraction  of  the  quadriceps  one  of  four  lesions  may  be  caused:  (1) 
Fracture  of  the  patella;  (2)  rupture  of  the  ligamentum  patellae;  (3) 
rupture  of  the  quadriceps  tendon;  (4)  dislocation  of  the  patella. 

Fracture  of  the  Patella. — Fracture  of  the  patella  is  the  commonest 
of  these.  The  fall  of  the  patient  is  usually  only  indirectly  the  cause  of  the 
fracture,  and  it  is  often  the  result.  In  a  fall  on  the  bent  knee,  when  the 
hip  is  also  flexed,  the  tubercle  of  the  tibia  and  not  the  patella  comes  in 
contact  with  the  ground.  In  some  cases,  however,  the  patella  is  broken 
by  direct  violence,  as  by  a  blow  or  a  fall  directly  on  the  bone.  In  over 
SO  per  cent,  of  cases  the  fracture  is  due  to  muscular  action,  which  is  a 
more  common  cause  of  fracture  in  case  of  the  patella  than  in  any  other 
bone.  The  line  of  fracture  is  quite  uniformly  transverse  or  slightly 
oblique  when  due  to  muscular  action,  and  usually  at  or  just  below  the 
centre  of  the  bone.  Fractures  due  to  direct  violence  may  be  transverse, 
oblique,  comminuted,  or  even  longitudinal.  Another  important  differ- 
ence lies  in  the  fact  that  in  direct  fractures  there  may  be  little  or  no  sepa- 
ration of  the  fragments,  in  indirect  fractures  there  is  usually  some  and 
often  considerable  separation.  This  separation  depends  upon  the  amount 
of  effusion  into  the  joint,  and  of  the  transverse  laceration  of  the  lateral 
patellar  ligaments  and  the  capsule.  The  influence  of  the  latter  is  seen 
in  direct  fractures,  in  which,  though  there  may  be  considerable  effusion, 
there  is  often  little  or  no  separation,  for  the  lateral  patellar  ligaments 
are  practically  intact,  unless  vigorous  or  repeated  action  of  the  quadriceps 
extensor  has  followed  the  fracture.  Again,  in  fractures  due  to  muscular 
action  the  lateral  patellar  ligaments  are  more  or  less  extensively  torn, 
but  the  separation  disappears  or  may  be  easily  overcome  if  the  effusion 
is  gotten  rid  of.  With  the  knee  extended  to  relax  the  quadriceps  tendon 
the  pull  of  the  latter  is  not  an  important  factor  in  the  separation  until 
later  on,  after  atrophy  of  the  muscle  occurs. 

The  rupture  of  the  lateral  patellar  ligaments  and  the  capsule  on  the 
rides,  and  the  failure  of  bony  union  are  explained  by  the  mechanism 
of  fracture  by  muscular  action  (Fig.  170).  In  the  semiflexed  position, 
in  which  the  knee  is  usually  placed  when  the  violent  contraction  of  the 
quadriceps  occurs,  only  the  middle  of  the  back  of  the  patella  rests  on  the 
trochlear  surface  of  the  femur,  the  upper  and  lower  ends  of  the  bone  being 
unsupported.  Its  vertical  axis  is  in  line  with  the  taut  ligamentum 
patellar,  while  the  line  of  nation  of  the  violently  contracted  quadriceps 
muscle  (indicated  by  the  upper  arrow  in  Fig.  176)  is  nearly  at  right  angles 

to  t;  The  patella  is  thus  broken  (is  one.  WOUld  break  a  stick  over  the 

knee.  It.  may  also  be  Fractured  by  direel  traction.  In  either  case  the  bone 
gives  way  firs!  and,  the  force  continuing,  the  fragments  are  separated 
and  the  tear  extends  a  variable  distance  into  the  lateral  patellar   liga- 


520 


THE  LOWER  EXTREMITY 


ments  and  the  capsule  on  either  side  of  the  line  of  fracture.  After 
the  patella  is  fractured,  and  the  fragments  begin  to  separate,  the  perios- 
teum and  tendinous  fibers  in  front  of  the  patella  do  not  tear  at  once,  but 
stretch  a  certain  distance.  But  if  the  fragments  are  pulled  further  apart, 
these  fibrous  structures  give  way,  usually  at  a  level  different  from  that  of 
the  fracture  (above  or  below)  and  curl  back  in  front  of  one  or  both  frac- 
tured surfaces.  Atmospheric  pressure  acting  on  the  gap  between  the  frag- 
ments may  help  to  force  these  fibrous  fringes  between  the  fragments. 
This  interposition  of  fibrous  tissue  between  the  fragments  prevents  the 
bony  union  of  these  surfaces  and  often  prevents  crepitus  when  the  sur- 
faces are  rubbed  together.     The  interposition  of  blood  clot  and  synovial 


Fig.  176 


Schematic  outline  of  the  knee  joint  to  show  the  mechanism  of  fracture  of  the  patella 
by  muscular  action.  The  upper  arrow  represents  the  line  of  action  of  the  quadriceps  muscle; 
L,  the  ligamentum  patella. 

fluid  may  contribute  to  prevent  bony  union.  This  is  the  reason  why  treat- 
ment by  open  operation,  in  this  the  commonest  variety  of  fracture  of  the 
patella,  is  in  such  favor,  as  it  alone  assures  bony  union.  In  the  open 
operation  the  fibrous  tissue  between  the  fragments  must  be  trimmed 
away  and  the  blood  clot  removed.  The  tear  in  the  capsule  and  the  lateral 
expansions  should  be  carefully  sutured  and  the  fragments  brought  in 
apposition  by  absorbable  periosteal  sutures,  with  as  little  handling  of 
the  joint  as  possible.  In  direct  fractures  I  have  secured  bony  union 
without  operation,  and  this  result  is  by  no  means  rare.  A  fracture  of  the 
lower  and  non-articular  end  of  the  patella  without  injury  of  the  synovial 
membrane  is  an  anatomical  possibility,  provided  the  amount  of  separa- 
tion is  slight  (Morris).     In  such  a  case  the  fat  behind  the  lower  end 


THE  REGION  OF  THE  KNEE  521 

of  the  patella  saves  the  synovial  membrane  from  injury.  The  patella, 
which  is  a  sesamoid  bone  developed  in  the  quadriceps  tendon,  does  not 
ossify  until  the  end  of  the  second  year,  and  may  be  congenitally  absent. 
Sesamoid  bones  are  said  to  exhibit  a  tendency  to  repair  by  fibrous  union, 
and  this  may  have  a  bearing  on  the  common  occurrence  of  fibrous 
union  after  fracture  of  the  patella.  Nearly  all  the  arteries  around  the 
joint  furnish  blood  to  it. 

Rupture  of  the  Ligamentum  Patellae. — Rupture  of  the  ligamentum 
patellae  is  rare.  Exceptionally  the  tendon  is  torn  from  its  insertion 
into  the  tubercle  of  the  tibia,  and  rarely  (ten  recorded  ca-es)  the  tubercle 
is  avulsed  with  the  tendon. 

Rupture  of  the  Quadriceps  Tendon. — Rupture  of  the  quadriceps 
tendon  above  the  patella  is  more  common,  but  rare  in  comparison  with 
fractures  of  the  patella.  It  results  from  a  violent  muscular  contraction, 
sometimes  from  a  slight  one  when  the  muscle  is  diseased.  A  well-marked 
depression,  occupied  by  a  blood  clot,  is  palpable  and  often  visible  above 
the  patella.  It  may  be  partial  or  complete.  Complete  rupture  of  the 
tendon  or  ligament  is  treated  by  aseptic  suture.  In  these  three  forms 
of  injury  the  ability  to  extend  the  knee  is  lost  or  impaired. 

Dislocation  of  the  Patella. — Dislocation  of  the  patella  is  rare.  The 
commonest  form  is  the  outward  dislocation,  which  may  be  complete 
or,  more  often,  incomplete.  It  may  be  caused  by  a  blow  on  the  prominent 
inner  border  or,  more  commonly,  by  a  violent  contraction  of  the  quad- 
riceps muscle.  It  occurs  most  often  in  the  extended  position  of  the  limb, 
when  the  front  of  the  capsule  and  the  lateral  ligaments  of  the  patella  are 
most  lax,  and  the  patella  is  more  prominent  and  exposed  to  direct  vio- 
lence. The  line  of  action  of  the  quadriceps,  in  the  axis  of  the  femur,  is 
not  the  same  as  the  axis  of  the  patellar  ligament,  in  the  axis  of  the  tibia. 
When,  therefore,  the  quadriceps  contracts,  the  patella,  which  lies  at  the 
angle  of  meeting  of  these  two  axes,  is  pulled  outward,  as  the  muscle  and 
ligament  tend  to  form  a  straight  line.  In  knock-knee,  therefore,  the 
tendency  to  outward  dislocation  is  increased  by  the  greater  angle  betweeen 
the  muscle  and  the  ligament.  The  outward  dislocation  of  the  patella  is 
resisted  by  the  prominent  outer  margin  of  the  trochlear  surface  of  the 
femur  and  by  the  capsule  and  the  internal  expansion  of  the  quadriceps. 
The  latter  may  remain  intact  in  an  incomplete  dislocation,  but  must  be 
ruptured  to  allow  a  complete  outward  dislocation.  In  the  latter  form  the 
•patella  is  displaced  to  the  outer  side  of  the  external  condyle,  and  usually 
ties  with  the  inner  border  directed  forward  and  the  posterior  surface 
inward.  In  the  production  of  the  dislocation  the  patella  may  be  raised 
by  the  quadriceps  so  as  to  pass  outward  above  the  prominent  outer 
margin  of  the  trochlea.  The  next  most  common  form  is  the  so-called 
edgewise  or  vertical  dislocation  of  the  patella.  In  (lie  commoner  variety 
of  this  form  tin-  inner  border  rests  in  or  near  the  bottom  of  the  trochlear 
groove  with  the  outer  border  projecting  forward  and  the  anterior  surface 
looking  inward.  This  position  is  maintained  by  the  tension  of  its  fibrous 
attachments  and  the  untorn  portion  of  the  capsule  and  the  pressure  of 
the  overlying  fascia  and  skin,  like  "a  stick  on  end  under  a  tightly  stretched 


522  THE  LOWER  EXTREMITY 

sheet"  (Stimson).  The  reverse  displacement  is  nearly  as  common. 
Muscular  action,  not  always  violent,  seems  to  be  the  most  common  cause 
of  this  form  also,  but  it  may  be  due  to  a  blow  on  the  inner  edge  of  the 
bone.     Inward  dislocations  are  rare. 

The  semilunar  cartilages  are  attached  by  their  peripheral  surfaces  to 
the  capsule  and  lateral  ligaments  of  the  knee.  In  effusions  into  the 
joint  one  sees  a  groove  in  the  bulging  capsule  on  either  side  of  the  lower 
end  of  the  patella,  due  to  the  lateral  patellar  ligaments  and  to  this  attach- 
ment of  the  semilunar  cartilages,  which  incompletely  divide  the  syno- 
vial cavity  into  an  upper  larger  and  a  lower  smaller  portion.  Dislo- 
cation of  one  or  the  other  of  the  semilunar  cartilages  occurs,  as  a  rule, 
from  a  twist  of  the  leg  in  the  semiflexed  position  of  the  joint.  Flexion 
and  extension  of  the  knee  occurs  between  the  femur  and  these  cartilages 
which  move  with  the  tibia,  but  in  rotation  one  or  the  other  disk  is  held 
firmly  between  the  two  bones,  while  the  other  is  liable  to  be  pressed  or 
dragged  so  as  to  be  nipped  between  them.  Thus  in  rotation  outward,  per- 
formed chiefly  by  the  biceps,  the  external  meniscus  is  held  closely  between 
the  outer  condyle  and  the  tibia,  as  these  two  are  pressed  together  by  the 
biceps.  This  increases  the  gap  between  the  internal  condyle  and  the 
tibia,  into  which  the  internal  disk  is  liable  to  slip.  Similarly  in  internal 
rotation  the  outer  disk  is  the  one  liable  to  displacement.  Hence  the 
rule  that  dislocation  of  the  internal  disk  occurs  from  an  outward  twist 
of  the  knee,  that  of  the  external  disk  from  an  inward  twist.  The  internal 
disk  is  dislocated  more  than  three  times  as  often  as  the  external,  and  the 
left  knee  is  affected  nearly  three  times  as  often  as  the  right.  This  may  be 
partly  accounted  for  by  the  fact  that  outward  rotation  is  more  common 
than  inward,  and  that  the  external  cartilage  is  smaller,  rounder,  and  more 
movable  than  the  internal,  and  is  attached  partly  to  the  posterior  crucial 
ligament  behind,  and  thereby  to  the  femur,  while  the  anterior  crucial 
ligament  is  attached'  in  front  of  and  often  to  its  anterior  cornu,  limiting 
its  forward  displacement.  The  popliteus,  the  chief  internal  rotator, 
grooves  its  outer  surface,  postero-externally,  and  may  help  to  hold  and 
steady  it  when  it  contracts  in  internal  rotation.  The  dislocated  cartilage 
is  torn  from  its  attachment  to  the  tibia,  usually  at  one  end,  and  is  displaced 
forward  in  most  cases.  At  times  it  is  pulled  into  the  joint  during  flexion 
and  rotation,  where  it  becomes  pinched  and  locked  between  the  two  bones, 
giving  rise  to  a  sudden  pain  and  fixation  of  the  knee  in  the  flexed  position, 
followed  by  a  synovitis.  On  palpating  the  line  of  the  joint  we  may 
feel  a  gap,  when  the  disk  is  displaced  into  the  joint,  or  a  marked  ridge 
when  it  is  displaced  laterally.  The  displacement  can  usually  be  reduced 
by  extension  followed  by  sudden  flexion  and  rotation;  but  an  operation 
is  often  required  to  effect  a  cure,  by  removing  the  loose  portion  or  suturing 
it  in  position. 

The  Synovial  Membrane. — The  synovial  membrane  of  the  knee 
is  the  most  extensive  and  complicated  in  the  body.  It  extends  as  a  pouch 
between  the  quadriceps  and  the  front  of  the  femur  for  about  2.5  cm.  (1  in.) 
above  the  trochlear  surface  of  the  femur  and  the  upper  end  of  the  patella. 
Above  the  pouch  is  a  bursa  (subcrural)  between  the  quadriceps  and  the 


PLATE   LIII 


SUBCBUREUS 
MUSCLE 


POPLITEUS 
TENDON 
FAT   BENEATH 
LIG.    PATELUE 

EXT.    LATERAL. 

LIGAMENT 

BICEPS    TEN- : 

DON 

BURSA    BENEATH 
LIG.    PATELLA 


ANT.   TIBIAL 
ARTERY 


SUBCRURAL 
BURSA 

QUADRICEPS 
TENDON 


NT.    LATERAL 
PATELLAR 
LIGAMENT 


NT.    SEMI- 
LUNAR  CAR- 
TILAGE 


INT.  HAMSTRING 
TENDONS,  WITH 
BURSA    BENEATH 


Knee  Joint  from  in  Front,  showing  synovial  sae,  anterior 
ligaments,  superficial  anastomosis  of  articular  arteries,  etc. 
(Testut. ) 

FIG   173. 


SUBCRU 
BURS 


PREPATELLAR 
BURSA 

LIGAMENTUM 
MUCOSUM 

LIGAMENTUM 
PATE  LL/E 

BURSA 


POPLITEAL 
VEIN 

ANT.    CRUCIAL 
LIGAMENT 

POST.     LIGAMENT 
I   _  ^XT.    SEMILUNAR 
CARTILAGE 

POPLITEAL 
ARTERY 


POPLITEUS 
MUSCLE 


GASTROCNEMIUS 
MUSCLE 


Lateral    Half  or    Vertical    Sagittal    Section    of    Right    Knee    after 
Distention  of  the  Synovial  Sac.  (Joessel.) 

Iv.li.-  pawed  through  opening  between  pouch  above  patella  and  subcrural  buna, 


THE  REGION  OF  THE  KNEE  523 

front  of  the  femur,  over  2.5  cm.  ( I  in.)  long  vertically,  which  c ini- 

cates  with  the  pouch  in  70  per  cent,  of  cases  in  children  and  80  per  cent, 
in  adults.  The  partition  varies  from  a  complete  septum  to  a  mere  trace. 
In  the  extended  position,  therefore,  we  may  find  a  synovial  cavity,  con- 
tinuous with  the  joint,  over  5  cm.  (2  in.)  above  the  patella  or  the  trochlear 
surface  of  the  femur,  so  that  an  anterior  wound  or  incision  at  this  level 
may  practically  open  into  the  joint  in  a  majority  of  cases.  In  exten- 
sion the  pouch  is  supported  or  pulled  up  by  the  subcrureus, while  in  flexion 
it  is  somewhat  drawn  down.  In  case  of  effusion  into  the  joint  the  pouch 
and  bursa  appear  as  a  median  prominence,  or,  if  separate  and  both  are 
filled  with  eifusion,  as  two  prominences  above  the  patella.  In  this 
condition  of  effusion  into  the  joint  the  patella  is  raised  from  the  trochlear 
surface  of  the  femur,  on  account  of  its  connection  with  the  anterior 
part  of  the  capsule,  and  is  said  to  "float."  J5y  sudden  pressure  on  the 
patella  the  latter  is  made  to  strike  the  femur, producing  a  click,  which  is 
useful  as  a  diagnostic  sign  of  fluid  in  the  joint.  To  produce  this  it  is 
important  to  pull  or  press  down  the  anterior  thigh  muscles  so  as  to  relax 
the  tension  of  the  quadriceps,  which  may  be  sufficient  to  hold  the  patella 
applied  to  the  femur  and  prevent  its  floating. 

The  attachment  of  the  posterior  crucial  ligament  to  the  posterior 
ligament  divides  the  synovial  cavity,  posteriorly,  into  an  inner  mid  an 
outer  condylar  rex-ess.  The  upper  third  of  the  ligamentum  patellar  is 
separated  from  the  synovial  membrane  by  a  pad  of  fat,  the  lower  two- 
thirds  from  the  tibia  by  fat  and  a  bursa.  The  synovial  membrane  is 
remarkable  for  the  number  of  fringes  from  its  inner  surface,  (specially 
about  the  patella.  Laceration,  contusion,  or  pinching  of  these  fringes, 
followed  by  their  infiltration  with  blood,  causes  diem  to  become  enlarged 
and  liable  to  be  caught  and  pinched  between  the  joint  surfaces,  causing 
pain  and  often  synovitis.    Their  subsequent  exfoliation  may  give  origin 

nine  of  the  "loose  bodies"  in  the  knee  joint.  Fibrinous  or  calcareous 
thickening  in  the  synovial  fringes,  due  to  osteoarthritis,  or  embryonic 
remnants  of  cartilage  in  them, or  the  organization  of  an  intra-articular 

clotorof  fibrinous  deposits  in  the  joint  may  also  produce  similar  "loose 
bodi- 

Synovitis.  Synovitis  from  injury  or  exposure  to  cold  is  more  fre- 
quent in  the  knee  joint  than  elsewhere,  owing  to  its  superficial  and  ex- 
posed po  ition  and  its  exposure  to  wrenches  and  strains  on  account  of 
the  leverage  of  the  long  bones  on  either  side  of  it.  The  floating  of  the 
patella  and  the  bulging  of  the  synovial  sac  above  and  at  the  sides  of 
the  patella  have  already  been  referred  to  (see  above).  At  the  sides  of  the 
patella  the  bulging  u  ualrj  ihows  some  tran  verse  constriction,  owing 
t<>  the  re  i  tance  to  the  swelling  of  the  firm  lateral  patellar  ligaments. 
The  swelling  extend  from  5  cm.  (2  in.)  above  the  patella  nearly  to  the 
middle  of  the  ligamentum  patella;.  //'  chronic  inflammation  of  the  knee 
joint  the  latter  almo  t  alv  imes  the  flexed  position,  which  may  be 

parti;,  explained  as  follows:  (1)  The  capacity  of  die  joint  is  increased 
on  moderate  flexion,  being  greate  I  in  lie-ion  to  25  degrees  and  least  in 
complete  flexion.    The  l.nce,  therefore,  assumes  the  flexed  position  to 


524  THE  LOWER  EXTREMITY 

diminish  the  tension,  which  causes  pain  from  pressure  on  the  nerve 
endings.  (2)  Flexion  relaxes  most  of  the  ligaments  of  the  joint  (p.  518),  in- 
cluding the  firmest  and  most  resistant.  (3)  The  irritation  of  the  sensory 
nerves  of  the  joint  causes  a  reflex  contraction  of  the  muscles,  supplied  by 
the  same  nerves,  which  fix  the  joint  and  prevent  motion,  as  that  is 
painful.  The  flexor  muscles  are  more  numerous,  more  powerful,  and 
more  favorably  placed  for  acting,  and  hence  the  joint  is  flexed.  The 
flexed  position,  at  first  maintained  by  muscular  action,  is  later  on  fixed 
by  fibrous  or  bony  ankylosis.  If  softening  and  lengthening  of  the  liga- 
ments occur  from  the  joint  disease,  the  pull  of  the  flexor  muscles  may 
produce  a  posterior  dislocation  of  the  leg  on  the  thigh. 

To  drain  the  knee  joint,  incisions  may  be  made  on  both  sides  of  the 
patella  a  little  below  its  middle,  but  the  only  way  to  thoroughly  expose 
and  drain  aseptic  knee  is  to  carry  a  free  transverse  incision  into  the 
joint  below  the  patella,  turn  up  the  upper  flap,  and  flex  the  opened 
knee.  Owing  to  the  size  and  complexity  of  the  synovial  membrane 
acute  inflammation  is  apt  to  be  serious,  and  subacute  inflammation  to 
become  chronic. 

Excision  of  the  Knee. — Excision  of  the  knee  is  sometimes  required 
in  chronic  tuberculous  disease  (white  swelling),  or  in  case  of  a  knee 
ankylosed  from  any  cause  in  a  strongly  flexed  position.  Through  an 
incision  from  the  hind  part  of  one  condyle  to, that  of  the  other,  curving 
below  the  patella  the  joint  is  opened  and  the  upper  flap  turned  up. 
The  internal  saphenous  vein  and  nerve  need  not  be  divided.  When 
there  is  ankylosis  with  marked  flexion  we  may  remove  a  wedge-shaped 
segment  of  bone  with  the  base  anteriorly.  In  this  way  no  undue  traction 
is  made  on  the  popliteal  vessels.  In  sawing  the  femur  the  section  should 
be  parallel  with  the  normal  joint  surface,  not  at  right  angles  with  the 
shaft.  If  not  properly  sawed,  knock-knee  or  bowlegs  may  result.  Both 
bones  are  best  sawed  from  before  backward.  With  reasonable  care 
there  is  no  danger  of  wounding  the  popliteal  vessels,  although  there  is 
more  danger  while  sawing  the  tibia  than  the  femur  (see  p.  516).  The 
operation  should  be  done  in  such  a  way  that  the  limb  may  be  absolutely 
straight.  In  subjects  who  have  not  attained  their  growth  the  greatest 
care  must  be  taken  to  do  no  damage  to  the  epiphyseal  line,  for  the  greatest 
amount  of  growth  in  length  occurs  at  this  end  of  both  bones.  The  level 
of  the  epiphyseal  line  of  the  femur  has  already  been  given  (p.  512). 
The  lower  femoral  epiphysis  unites  with  the  shaft  about  the  twentieth 
year.  The  limits  of  the  upper  tibial  epiphysis  are  indicated  by  a  hori- 
zontal line  just  below  the  tuberosities,  behind  and  laterally,  so  as  to  in- 
clude the  attachment  of  the  semimembranosus  and  the  facet  for  the  fibula. 
In  front  it  slants  down  on  each  side  to  meet  just  below  the  tubercle, 
which  is  included  in  the  epiphysis.  It  unites  with  the  shaft  in  the  twenty- 
first  or  twenty-second  year.  Arthrectomy  of  the  knee  has  replaced  exci- 
sion to  a  large  extent,  and  is  preferable  in  suitable  cases. 

Disarticulation. — Disarticulation  at  the  knee  may  be  done  by  (1) 
lateral  flaps  (Stephen  Smith),  (2)  an  elliptical  incision,  or  (3)  a  long 
anterior  flap.    The  best  method  is  the  first.     In  the  method  by  a  long 


THE  LEG  525 

anterior  flap  there  is  danger  of  sloughing  of  the  flap.  All  methods  have 
the  disadvantage  of  leaving  a  large  surface  of  cartilage  which  has  little 
or  no  reparative  action.  Hence  I  prefer  Gritti's  method,  in  which  the 
lower  surface  of  the  condyles  and  the  articular  surface  of  the  patella 
are  sawed  off  and  the  sawed  surfaces  brought  together.  The  patella, 
with  the  tough  skin  covering  it,  then  forms  the  lower  end  of  the  stump. 

Fractures  of  the  Lower  End  of  the  Femur. — Besides  the  frac- 
tures of  the  shaft  above  the  condyles  (see  pp.  510-11)  we  find:  (1)  inter- 
condyloid fractures,  (2)  fractures  of  either  condyle,  and  (3)  separation 
of  the  epiphysis.  In  (1)  the  line  of  fracture  between  the  condyles  follows 
the  intercondyloid  notch  in  a  sagittal  plane  and  forms  a  T  with  the 
fracture  separating  both  condyles  from  the  shaft.  (2)  Fractures  of 
either  condyle  are  not  common,  and  may  be  due  to  avulsion  through  the 
lateral  ligaments,  direct  violence,  or  the  pressure  of  the  head  of  the 
tibia.  The  fracture  line  runs  into  the  intercondyloid  notch.  (3)  Sepa- 
ration of  the  lower  epiphysis  of  the  femur  occurs  more  often  than  that 
of  any  other  epiphysis.  It  is  commonly  due  to  great  violence,  acting 
especially  in  extending  or  abducting  the  knee.  With  singular  fre- 
quency it  has  been  due  to  the  leg  being  caught  between  the  spokes  of 
a  wheel.  The  separation  here,  as  elsewhere,  takes  place  between  the 
cartilage  and  the  shaft.  The  periosteum  is  freely  stripped  up  from 
the  shaft,  but  remains  attached  to  the  epiphysis.  The  epiphysis  is  com- 
monly displaced  forward  and  to  one  side,  usually  the  inner.  The  injury 
is  frequently  compound,  and  the  popliteal  vessels  have  been  torn  or, 
more  often,  obstructed  by  pressure.  Direct  reposition  has  sometimes 
failed,  owing  to  the  presence  of  prominent  lips  on  the  epiphysis  and  to 
the  tension  or  interposition  of  the  periosteum.  In  such  cases  operative 
reposition,  through  an  external  incision,  has  given  good  results.  Ampu- 
tation has  often  been  resorted  to  in  the  past,  and  several  instances  of 
arrest  of  growth  of  the  femur  have  been  reported. 

Fracture  of  the  Upper  End  of  the  Tibia.— This  fracture  is  not  com- 
mon, less  so  than  that  of  any  other  part  of  the  bone.  It  may  be  due  to 
severe  direct  or  indirect  violence,  and  the  line  of  fracture  may  or  may 
not  involve  the  articular  surface.  Owing  to  the  proximity  of  the  knee 
joint,  which  is  often  involved  directly  or  indirectly,  an  effusion  occurs 
within  the  joint.  Separation  of  the  upper  epiphysis  of  the  tibia  has 
been  observed  in  a  few  cases.  The  upper  end  of  the  tibia  and  the 
lower  end  of  the  femur  are  favorite  situations  for  osteosarcoma. 


THE  LEG. 

A  the  limits  of  this  region  we  may  take  the  level  of  the  tubercle  of 
the  tibia  above  and  thai  of  the  base  of  the  malleoli  below. 

Landmarks  and  Surface  Markings.— The  anterior  tibial  border  or 
"  liin"  can  be  fell  throughout  its  entire  length.  It  is  sharp  and  eurved 
outward  in  the  upper  two-thirds;  rounded,  less  prominent,  and  curved 
inward  in  its  lower  third,  where  it  fades  into  the  shaft  and  ends  in- 


526  THE  LOWER  EXTREMITY 

distinctly  in  front  of  the  internal  malleolus.  The  inner  border  can  also 
be  felt,  from  the  tuberosity  above  to  the  malleolus  below.  The  internal 
surface,  between  these  two  borders,  is  subcutaneous  except  above,  where 
it  is  covered  by  the  tendinous  insertion  of  the  sartorius  covering  those 
of  the  gracilis  and  semitendinosus.  Although  the  head  of  the  fibula 
is  easily  felt,  its  shaft  is  buried  by  the  overlying  muscles  in  its  upper  half. 
In  its  lower  half  it  becomes  palpable,  especially  in  the  lower  10  cm.  (4  in.), 
where  the  malleolus  and  the  triangular  surface  above  it  are  subcutaneous. 
This  subcutaneous  area  lies  between  the  peroneus  tertius  and  brevis. 
The  fibula  is  well  behind  the  tibia,  so  as  to  be  posterior  to  the  plane  of 
the  posterior  border  of  the  latter.  Anteriorly,  between  the  two  bones, 
we  can  see  the  outline  of  the  tibialis  anticus  internally,  and  external 
to  it  that  of  the  narrower  extensor  communis  digitorum  can  be  made 
out  when  in  action.  The  groove  separating  these  muscles  is  quite  dis- 
tinct in  muscular  subjects,  and  forms  the  best  guide  to  the  anterior  tibial 
artery.  In  the  lower  third  of  the  leg  the  tendon  of  the  extensor  longus 
pollicis  comes  to  the  surface  and  can  be  felt  between  these  two  muscles. 
Posteriorly  the  prominence  of  the  calf  is  mainly  formed  by  the  gastroc- 
nemius, whose  two  heads  are  conspicuous  when  one  stands  on  the  toes. 
In  this  position  it  is  seen  that  the  inner  head  is  larger  and  longer.  In 
the  same  position  the  Achilles  tendon  stands  out  in  prominent  relief 
from  about  the  middle  of  the  leg  to  the  heel.  The  soleus  comes  to  view 
on  either  side  of  this  tendon,  but  more  especially  externally,  where  it  is 
less  covered  by  the  gastrocnemius. 

Topography. — The  course  of  the  anterior  tibial  artery  is  indicated 
by  a  line  from  a  point  midway  between  the  head  of  the  fibula  and  the 
prominence  of  the  outer  tuberosity  of  the  tibia  to  the  middle  of  the 
front  of  the  ankle  joint,  or  of  the  space  between  the  malleoli.  The  pos- 
terior tibial  artery  runs  from  the  bifurcation  of  the  popliteal,  at  the  centre 
of  the  lower  end  of  the  popliteal  space,  opposite  the  lower  end  of  the 
tubercle  of  the  tibia  and  about  5  cm.  (2  in.)  below  the  joint,  to  the  mid- 
point of  a  line  from  the  tip  of  the  internal  malleolus  to  the  lower  and  inner 
corner  of  the  prominence  of  the  heel.  At  this  point  the  artery  bifurcates 
into  the  two  plantar  arteries.  About  2.5  cm.  (1  in.),  sometimes  less 
(15  mm.),  below  its  upper  end  the  posterior  tibial  gives  off  the 
peroneal  artery,  which  runs  along  the  inner  border  of  the  fibula  to 
about  2.5  cm.  (1  in.)  above  the  ankle  joint,  where  it  gives  off  the 
anterior  peroneal. 

The  internal  saphenous  vein,  arising  from  the  venous  arch  on  the 
dorsum  of  the  foot,  runs  in  front  of  the  internal  malleolus  and  thence 
just  behind  the  internal  border  of  the  tibia  to  the  level  of  the  knee, 
where  it  lies  just  behind  the  internal  condyle.  The  short  saphenous 
vein  passes  behind  the  external  malleolus  and  thence  up  the  back  of  the 
leg  to  the  lower  part  of  the  ham,  where  it  perforates  the  deep  fascia. 
Both  the  internal  and  external  saphenous  veins,  but  more  especially 
the  former,  are  visible  beneath  the  skin  unless  the  subcutaneous  fat  is 
very  abundant.  Both  of  the  saphenous  veins  and  of  the  tibial  arteries 
are  accompanied  by  nerves  of  the  same  name. 


PLATE  LIV 


FIG.   179 


INT.   SAPH 


TIBIALIS    POS 
MUSCL 
DEEP  TRANS 
VERSE    FASC 


POST.   TIBIAL 
ARTER 


PERONEAL 
ARTERY 


EXTENSOR    COM 

DIG.   MUSCLE 
INTEROSSEOUS 

MEMBRANE 
PERONEUS    LON- 

GUS    MUSCLE 
ANT.   TIBIAL, 
NERVE,   ART- 
ERY  AND   VEIN 


DEEP    FASCIA 
OF    LEG 


SOLEU 
MUSC 


CASTROCNE 
MU 


Cross-section  of  the  Lower   End  of  the   Upper  Third  of  the 
Right  Leg.     Lower  segment  of  the  section.     (Tillaux.) 


F!C.    180 


DEEP    LAYER 
OF    CRURAL 
FASCIA 


INT.   SAPHE- 
NOUS    VEIN 
INT.    SAPHE- 
NOUS   NERVE 


PLANTARIS 
TENDON 


-POST.   TIBIAL 

NCRVE 

POST.   TIBIAL 

ARTERY 


Interna)  Aspect  of  the  Lower  Half  of  Right  Leg.     Superficial 
dissection.     (Joessel.) 


THE  LEG  527 

The  skin  of  the  leg,  especially  anteriorly,  is  more  adherent  to  the  deep 
fascia  than  that  of  the  thigh.  Thus  in  circular  amputations  it  is  neces- 
sary to  dissect  up  the  skin  flap  and  not  merely  to  retract  it.  Owing  to 
the  conical  shape  of  the  leg,  it  may  be  difficult  or  impossible  to  dissect 
back  this  skin  flap  without  splitting  it  on  one  side  in  the  form  of  a  cuff. 
The  subcutaneous  tissue  of  the  leg,  especially  in  front,  contains  com- 
paratively little  fat,  so  that  the  skin  over  the  inner  surface  of  the  tibia 
lies  nearly  directly  on  the  bone.  The  skin  is  here  exposed  to  blows  and 
kicks,  which  produce  a  degree  of  pain,  bruising,  cutting,  ulceration,  or 
even  periostitis,  far  in  excess  of  what  a  similar  violence  would  produce 
elsewhere.  Ulcers  and  eczema,  as  the  result  of  varicose  veins,  are  com- 
mon in  front  of  the  leg,  and  run  a  very  chronic  course.  Ulcers  over  the 
bone  may  expose  the  latter,  lead  to  disease  of  its  surface,  and  result  in 
scars  that  are  adherent  to  the  bone. 

In  the  subcutaneous  tissue  lie  the  superficial  veins,  nerves,  and  lym- 
phatics. The  long  saphenous  vein  is  not  infrequently  double  in  the  leg, 
as  it  is  in  the  thigh,  the  second  trunk  lying  behind  the  regular  course  of 
the  first  trunk  (see  p.  526),  that  is,  farther  behind  the  internal  border  of 
the  tibia.  Most  of  the  superficial  lymph  vessels  accompany  the  long 
saphenous  vein,  and  the  majority  of  them  are  in  front  of  it,  while  the 
long  saphenous  nerve  usually  lies  behind  and  deeper  than  the  vein.  A 
few  superficial  lymph  vessels  accompany  the  short  or  external  saphenous 
vein  to  the  small  popliteal  nodes.  The  latter  lymph  vessels  and  the 
short  saphenous  vein  and  nerve  are  covered  by  a  duplication  of  the  deep 
fascia  so  that  they  are  not  strictly  in  the  subcutaneous  tissue.  The 
musculocutaneous  nerve  perforates  the  deep  fascia  near  the  septum  be- 
tween the  peroneal  and  extensor  muscles  at  the  upper  end  of  the  lower 
third  of  the  leg.  Thence  it  runs  downward  and  inward  in  the  sub- 
cutaneous tissue,  so  superficially  that  it  is  easily  palpable,  or  even  visible 
in  thin  subjects. 

The  Deep  Fascia  (Fig.  180). — The  deep  fascia  closely  invests  the  leg 
and  in  its  upper  third  is  adherent  to  the  anterior  but  not  to  the  posterior 
muscles.  Although  it  is  attached  to  the  anterior  and  internal  borders  of 
the  tibia,  it  is  not  wanting  over  its  internal  surface,  as  stated  by  Tillaux, 
but  continues  over  this  surface  more  or  less  adherent  to  its  periosteum. 
It  is  attached  1<>  the  head  and  the  malleolus  of  both  tibia  and  fibula, 
where  it  blends  with  the  periosteum,  and  it  is  continuous  with  the  fascia 
lata  above  and  the  annular  ligaments  and  the  fascia  of  the  foot  below. 
Two  septa  passing  inward  from  the  deep  surface  of  this  fascia,  to  be 
attached  one  to  tin-  anterior  and  one  to  the  external  border  of  the  fibula, 
enclose  a  compartment  which  lodges  the  peroneal  muscles  and  separates 
an  anterior  from  a  posterior  compartment  externally.  These  two  main 
Compartments  are  further  separated  by  the  bones  and  the  interosseous 

ligament.     The  posterior  compartment  is  subdivided  into  a  superficial 

and  a  deep  portion  of  a  fibrous  septum,  the deep  transverse •fascia ,  which 
•  rom  the  interna]  border  of  the  tibia  to  thepostero-internal 
border  of  die  fibula,  leparating  the  soleus  behind  from  the  tibialis  pos- 
ticus in   front.      I'.elow  it  separates  the  tendo  Achillis  from  the  deeper 


528  THE  LOWER  EXTREMITY 

structures.  There  is  an  aponeurotic  expansion  in  the  substance  of  the 
soleus,  also  connected  with  the  internal  border  of  the  tibia,  which  may 
be  mistaken  for  the  deep  transverse  fascia  in  cutting  through  the  soleus 
to  expose  the  posterior  tibial  artery. 

The  Muscles.- — The  muscles  lodged  in  the  anterior  compartment 
are  so  compressed  within  their  firm  osseo-aponeurotic  walls  that  they 
form  a  protrusion  or  hernia  when  the  fascia  is  torn  or  cut.  The  plan- 
taris  tendon  has  not  infrequently  been  ruptured,  producing  a  sudden 
sharp  pain  in  the  calf.  The  tendo  Achillis,  less  often  some  fibers  of  the 
gastrocnemius,  may  be  ruptured  during  violent  exertion,  especially  at 
the  narrowest  and  weakest  point  of  the  tendon  about  3.5  cm.  (1|  in.) 
above  its  insertion,  or  opposite  the  internal  malleolus.  But  more  often 
it  requires  tenotomy  on  account  of  its  contracture.  This  is  best  done 
opposite  its  narrowest  point  by  introducing  the  tenotome  in  front  of  the 
tendon  at  its  inner  margin,  to  avoid  the  posterior  tibial  vessels,  and  then 
cutting  toward  the  surface.  The  posterior  tibial  vessels,  however,  lie 
beneath  the  deep  transverse  fascia  and  so  far  forward  that  they  are  in 
no  danger  of  injury  with  ordinary  care.  The  short  saphenous  vein  is 
nearer,  usually  in  front  of  the  outer  margin  of  the  tendon,  and  may 
possibly  be  wounded.  Its  accompanying  nerve  is  usually  in  front  of 
the  vein  at  this  point.     On  section  the  tendon  retracts  within  its  sheath. 

The  Vessels. — The  anterior  tibial  and  the  peroneal  arteries,  from 
their  close  relations  with  the  tibia  and  fibula  respectively,  are  liable  to 
be  injured  in  fracture  of  these  bones.  I  have  seen  gangrene  of  the 
foot  follow  the  rupture  of  the  anterior  tibial  artery  in  a  bad  fracture  of 
the  tibia.  The  anterior  tibial  artery  lies  on  the  interosseous  membrane 
in  the  upper  two-thirds  and  in  front  of  the  tibia  in  the  lower  third.  It 
lies  in  the  first  intermuscular  interval  on  the  outer  side  of  the  tibia,  but 
the  whitish  line,  which  is  said  to  indicate  this  interval  on  the  surface  of 
the  deep  fascia,  is  always  indistinct  and  usually  absent.  The  interval  can 
be  felt  better  than  seen,  and  lies  about  2.5  to  3  cm.  (1  to  1*  in.)  from  the 
crest  of  the  tibia  and  a  finger's  breadth  internal  to  the  septum  between 
the  peroneus  longus  and  the  extensor  communis  muscles.  The  posterior 
tibial  artery  in  the  upper  two-thirds  of  the  leg  is  covered  by  the  inner 
head  of  the  gastrocnemius  and  the  soleus,  the  former  of  which  must  be 
retracted  outward,  the  latter  divided  to  reach  the  artery.  The  longi- 
tudinal incision  is  carried  18  mm.  (f  in.)  behind  the  inner  border 
of  the  tibia,  where  the  long  saphenous  vein  is  to  be  avoided.  The 
artery  is  covered  by  the  deep  transverse  fascia  in  all  parts  of  the  leg,  so 
that  this,  as  well  as  the  deep  fascia,  must  be  divided  to  expose  it  (Fig.  180). 
In  the  lower  third  of  the  leg  it  becomes  more  superficial,  being  covered  only 
by  the  skin  and  deep  fasciae  (two  layers),  and  in  thin  persons  it  can  be 
felt  pulsating  in  the  hollow  on  the  inner  side  of  the  tendo  Achillis.  It 
is  not  often  involved  in  fractures  of  the  tibia,  as  it  is  separated  from 
it,  except  at  its  lower  end,  by  the  tibialis  posticus  muscle.  The  peroneal 
artery  in  the  greater  part  of  its  course  is  covered  by  the  flexor  longus 
hallucis,  which  must  be  divided  or  retracted  in  order  to  reach  it.  This 
artery  also  is  beneath  (anterior  to)  the  deep  transverse  fascia.     The 


THE  LEG  529 

peroneal  artery,  by  anastomotic  branches  at  the  lower  end  of  the  leg, 
takes  the  place  of  the  posterior  and  anterior  tibial  arteries  when  the  latter 
are  rudimentary  or  wanting.  The  bifurcation  of  the  popliteal,  or  some- 
times that  of  the  short  tibioperoneal  trunk,  is  where  emboli  are  apt 
to  lodge.  If  gangrene  results,  as  not  infrequently  happens,  the  embolus 
is  probably  at  the  bifurcation  of  the  popliteal,  for  in  this  case  all  three 
trunks  are  blocked.  According  to  Joessel,  not  only  the  two  regular  vense 
comites,  but  other  veins,  anastomosing  across  the  artery,  accompany 
the  posterior  tibial  and  increase  the  difficulty  of  its  ligation. 

Varicose  Veins. — Verneuil  thinks  that  the  deep  veins  of  the  leg  are  more 
often  varicose  than  those  of  the  surface,  and  that  this  condition  is  indi- 
cated by  aching  of  the  legs  and  swelling  of  the  feet  in  those  who  stand  a 
great  deal.  Varicose  veins  are  more  common  in  the  leg  than  elsewhere, 
with  the  possible  exception  of  the  spermatic  and  hemorrhoidal  veins. 
This  fact  may  be  partly  accounted  for  by  (1)  the  length  of  the  veins  of  the 
lower  extremity,  (2)  the  action  of  gravity  in  resisting  their  upward  flow 
and  in  affecting  the  weight  of  the  blood  column  which  the  valves  have 
to  support,  (3)  the  liability  to  compression  from  the  use  of  garters  or 
from  abdominal  or  pelvic  growths  or  the  pregnant  uterus  pressing  on 
the  external  iliac  trunk,  which  these  veins  ultimately  enter.  These  causes 
act  by  increasing  the  pressure  within  the  veins.  Additional  predisposing 
causes  are  (4)  the  loose  support  of  the  superficial  veins  and  the  lack 
of  the  assistance  of  muscular  contraction,  for  the  saphenous  veins  are 
thin- walled  and  lie  outside  of  the  firm  deep  fascia;  (5)  the  increased 
resistance  to  the  venous  circulation  where  the  superficial  join  the  deep 
veins,  and  where  varicosities  often  begin;  (6)  congenital  defects  in  the 
valves.  Varicose  veins  are  enlarged  not  only  in  diameter  but  in  length, 
hence  their  tortuous  course.  The  contour  is  irregular  and  nodular,  and 
the  nodules,  or  enlargements  of  the  vein,  are  found  especially  just  above 
the  valves  and  at  points  where  the  vein  is  joined  by  deep  veins.  At  the 
latter  points  pressure  is  exerted  from  three  directions:  (1)  the  weight 
of  the  blood  column  above,  (2)  the  blood  current  and  the  resistance  of 
the  valve  next  below,  and  (3)  the  inflow  from  the  side,  the  force  of  which 
is  increased  by  muscular  contraction.  I  have  seen  men  who  could 
produce  varicose  veins  at  will  by  an  upward  movement  of  the  deep 
fascia,  which  cut  oft",  as  it  were,  the  saphenous  veins  where  they  pene- 
trate it. 

The  Bones  of  the  Leg. — The  tibia  bears  the  entire  superincum- 
bent weight.  The  fibula,  besides  all'ording  attachment  to  muscles,  plays 
an  important  part  in  the  ankle  joint  and  serves  as  a  brace  for  the  tibia, 
which  inerea-.i  it-  p  -i  hmce  to  lateral  strains.  The  smallest  and  weak- 
est part  of  the  tibia  is  at  the  junction  of  the  middle  and  lower  thirds, 
where,  for  it  area,  it  bears  a  greater  weight  than  any  other  bone  (Hum- 
phry;. The  meeting  hereof  the  two  columns,  an  upper  and  a  lower, 
into  which  the  cancellous  tissue  is  divided  (Fay el  and  Duret),  and  of 
the  triangular  upper  two-thirds  and  the  circular  lower  third,  are  thought 
to  add  to  the  weakness  of  the  tibia  at  this  point.    Accordingly  this  is 

Where   most   indirect  fractures  occur. 
84 


530  THE  LOWER  EXTREMITY 

Direct  fractures  of  the  shaft  of  the  tibia  may  occur  at  any  point, 
and  are  often  more  or  less  transverse,  so  that  there  is  little  if  any  dis- 
placement. If  the  fibula  is  broken  at  the  same  time,  as  it  is  likely  to 
be,  the  fractures  of  the  two  bones  are  about  on  the  same  level.  The 
long,  slender  fibula,  placed  as  it  is  on  the  more  exposed  aspect  of  the 
leg,  would  apparently  be  more  often  broken  from  direct  violence  but 
for  its  covering  of  muscles.  When  one  bone  alone  is  broken,  the  other 
acts  as  a  splint  and  limits  its  displacement. 

Indirect  fractures  are  due  especially  (1)  to  a  bending  or  flexion,  or 
(2)  to  violence  combined  with  torsion  of  the  limb.  In  (1)  the  fracture 
may  be  at  any  point  and  is  more  or  less  transverse  and  dentated,  hence 
there  is  little  but  angular  deformity.  In  (2)  the  fracture  is  mostly 
in  the  upper  end  of  the  lower  third  (the  weakest  part)  and  is  oblique, 
the  line  of  fracture  usually  running  downward,  inward,  and  forward. 
The  fibula,  which  is  almost  always  broken  in  indirect  fractures,  breaks, 
as  a  rule,  at  a  higher  level.  The  sharp,  lower  end  of  the  upper  fragment 
of  the  tibia  is  liable  to  puncture  the  skin  and  compound  the  fracture 
from  within.  In  one  variety  of  this  form  of  fracture,  first  described 
by  Gosselin,  the  sharp  ends  of  both  fragments  end  in  a  triangular  point, 
and  from  the  bottom  of  the  depression  in  the  lower  fragment  antero- 
internally,  corresponding  to  the  point  of  the  upper  fragment,  a  fissure 
runs  spirally  downward  and  often  enters  the  ankle  joint. 

Owing  to  the  subcutaneous  position  of  the  tibia,  its  fractures  are 
frequently  compounded,  from  within  in  indirect  fractures,  from  without 
or  within  in  direct  fractures.  On  the  subcutaneous  inner  surface  and 
anterior  border  we  can  detect  even  very  slight  displacements  as  well 
as  other  pathological  conditions.  In  oblique  fractures  the  lower  frag- 
ment is  often  drawn  upward  and  outward,  behind  the  upper  fragment, 
by  the  calf  muscles  and  rotated  outward  by  the  weight  of  the  foot;  which 
has  lost  its  continuity  with  the  upper  leg. 

The  tibia,  more  than  any  other  bone,  becomes  bent  in  children  with 
rickets.  The  bowing  in  "bowlegs"  is  usually  outward,  at  times  forward 
or  outward  and  forward,  giving  a  kind  of  spiral  twist.  It  is  caused  by 
a  tonic  contraction  of  the  muscles,  and  is  increased  by  the  weight  of 
the  child  in  walking.  It  is  generally  most  prominent  at  the  weakest 
part  of  the  bone,  the  junction  of  the  lower  and  middle  thirds.  Genu 
varum,  in  which  the  femur  is  abducted  and  rotated  out  and  the  tibia 
rotated  in,  causing  a  separation  of  the  knees,  is  usually  associated  with 
some  degree  of  bowlegs  and  the  latter  with  some  genu  varum,  so  that 
the  terms  are  often  used  synonymously. 

Infectious  bone  disease,  septic  or  tuberculous,  is  most  common  near 
the  two  epiphyses  and  at  the  weak  point  in  the  bone,  which  are  par- 
ticularly subject  to  strains,  traumatisms,  etc.  If  neglected  they  may 
invade  the  neighboring  joint.  The  inner  surface  and  anterior  border 
are  favorite  situations  for  syphilitic  nodes  and  periostitis,  giving  these 
parts  a  rough,  irregular  feeling. 

In  amputation  of  the  leg  in  the  upper  third  the  "  place  of  election"  is 
a  hand's  breadth  below  the  knee  joint.     This  point  was  chosen  as 


THE  ANKLE  531 

giving  a  convenient  length  of  leg  stump  for  wearing  a  peg  leg;  for  the  knee 
is  then  bent  and  the  weight  is  borne  on  the  tubercle  of  the  tibia.  This 
line  of  amputation  is  at  or  just  above  the  large  nutrient  artery  of  the 
tibia,  which  therefore  does  not  cause  trouble,  as  it  may  below.  At 
this  level  three  arterial  trunks  are  met  with,  for  the  tibioperoneal  trunk 
bifurcates  7.5  cm.  (3  in.),  or  slightly  less,  below  the  knee  joint.  Through- 
out the  leg  the  two  posterior  arteries  are  beneath  the  deep  transverse 
fascia,  or  in  a  duplication  of  it,  the  peroneal  behind  the  fibula,  the 
posterior  tibial  behind  the  tibia  and  separated  from  it  by  the  tibialis 
posticus  and  the  flexor  longus  digitorum.  The  anterior  tibial  is  to  be 
sought  in  front  of  the  interosseous  membrane  in  the  upper  two-thirds 
and  in  front  of  the  tibia  below  this.  In  the  upper  third  of  the  leg  am- 
putation by  long  external  flap  is  the  best  method,  provided  care  is  used 
to  preserve  the  anterior  tibial  artery  to  the  end  of  the  flap,  and  not  to 
bare  the  bone  so  high  as  to  run  the  risk  of  injuring  this  artery  where  it 
comes  forward  above  the  interosseous  membrane.  Circular  amputa- 
tion is  also  suitable  in  the  upper  half,  but  less  so  below,  on  account  of 
the  conical  shape  and,  in  the  lower  third,  the  lack  of  a  muscular  cover- 
ing. In  the  middle  third  amputation  by  a  long  posterior  flap,  including 
the  superficial  layer  of  muscles  (Lee)  or  both  superficial  and  deep 
muscles  (Hey),  is  a  favorite  method.  Owing  to  the  danger  of  injury 
to  the  overlying  skin  from  the  pressure  of  the  sharp  angle  of  the  shin, 
this  angle  should  always  be  bevelled  off  after  sawing  the  tibia. 


THE  ANKLE. 

The  limits  of  this  region  are  artificial,  and  may  be  placed  two  fingers' 
breadth  above  and  below  the  malleoli. 

Landmarks  and  Surface  Markings. — The  two  malleoli  are  promi- 
nent and  very  distinctly  outlined.  The  external  lies  opposite  the  centre 
of  the  joint,  descends  lower  by  12  mm.  (\  in.),  is  slightly  less  prominent, 
arid  is  1_'  nun.  (£  in.)  behind  the  inner  malleolus,  anteriorly.  But  as  the 
latter  is  broader  anteroposteriorly,  the  posterior  borders  of  the  two  are  on 
the  same  level.  The  tip  of  the  external  malleolus  lies  opposite  the  pos- 
terior calcaneoscaphoid  joint.  According  to  Holden,  the  inner  edge  of  the 
patella,  the  internal  malleolus,  and  the  inner  side  of  the  great  toe  should 
be  in  the  same  vertical  plane,  a  fact  to  be  noticed  in  setting  fractures. 
///  front  of  the  ankle  the  extensor  tendons  form  a  prominence,  which 
is  very  marked  when  they  are  in  action  in  flexion  of  the  ankle.  From 
within  outward  we  can  distinguish  the  tendons  of  the  tibialis  anticus 
(the  most  superficial),  the  extensor  longus  hallucis,  and  the  extensor 
longus  digitorum,  with  the  peroneus  tertius.  On  either  side  of  the 
prominence  due  to  the  tendons  and  in  front  of  each  malleolus  is  a  slight 

depression.  Opposite  the  joint  line  this  depression  corresponds  to  the 
thin  anterior  part  of  the  capsule,  and  hence  it,  is  replaced  hi)  abul'jing 
in  sprains,  effusions  into  the  joint,  tuberculous  disease  of  the  latter,  etc. 
The    teitdo    AchUllS   forms    a    marked    prominence    behind.      On,   either 


532 


THE  LOWER  EXTREMITY 


side  of  it,  between  it  and  the  malleolus,  is  a  marked  furrow.  Along 
the  inner  furrow,  behind  the  inner  margin  of  the  tibia  and  the  back  of 
the  malleolus,  the  tendon  of  the  tibialis  posticus  can  be  felt,  and  behind 
and  external  to  it  that  of  the  flexor  longus  digitorum.  Behind  the 
external  malleolus  the  long  and  short  peroneal  tendons  are  palpable, 
the  tendon  of  the  peroneus  brevis  being  nearer  to  the  bone. 

Topography. — The  line  of  the  ankle  joint  is  12  mm.  (^  in.)  above  the 
tip  of  the  internal  malleolus.  Opposite  the  bend  of  the  ankle  the  an- 
terior tibial  artery  becomes  the  dorsalis  pedis,  and,  with  the  anterior 


TIBIALIS  POSTICUS 
MUSCLE 

INTEROSSEOUS 
LIGAMENT 

FLEXOR   LONGUS 
DIGITORUM   MUSCLE 

INT.    PLANTAR  NERVE 

FLEXOR  LONGUS 

HALLUCIS   MUSCLE 

FLEXOR   ACCES 

SORIUS  MUSCLE 

EXT.   PLANTAR   NERVE 

ABDUCTOR 

HALLUCIS 

MUSCLE 

FLEXOR  BREVIS 

DIGITORUM 

MUSCLE 


Fig.  181 


MALLEOLUS 

PERONEUS   BREVIS 
'MUSCLE 

PERONEUS  LONGUS 
MUSCLE 


ABDUCTOR   MINIMI 
DIGITI    MUSCLE 


Frontal  section  of  the  right  ankle,  seen  from  behind. 


tibial  nerve,  lies  between  the  tendons  of  the  extensors  longus  hallucis 
and  longus  digitorum,  where  its  pulsation  can  be  felt.  The  line  of  the 
artery  is  from  the  middle  of  the  ankle  to  the  proximal  end  of  the  interval 
between  the  first  and  second  metatarsal  bones.  In  some  cases  it  de- 
scribes a  curve,  concave  internally.  The  posterior  tibial  artery  and  nerve 
lie  behind  the  internal  malleolus,  external  and  a  little  posterior  to  the 
tendon  of  the  flexor  longus  digitorum.  The  tendon  of  the  flexor  longus 
pollicis  lies  still  more  externally,  at  the  back  of  the  lower  end  of  the 
tibia,  midway  between  the  two  malleoli.     The  posterior  tibial  artery 


PLATE  LV 


FIG.   182 


The  Anterior  Annular  Ligament  of  the  Ankle  and  the 
Synovial  Membranes  of  the  Tendons  Beneath  it  Artificially 
Distended.     (Gerrish,  after  Testut.) 


THE  ANKLE  533 

bifurcates  into  the  two  plantar  arteries  opposite  the  mid-point  of  a  line 
between  the  tip  of  the  internal  malleolus  and  the  lower  and  inner  corner 
of  the  prominence  of  the  heel.  The  long  saphenous  vein  ascends  in 
front  of  the  internal  malleolus,  the  short  saphenous  behind  the  external 
malleolus. 

The  Skin. — The  skin  covering  the  ankle  is  thin  and  loosely  attached, 
and  rests  almost  directly  upon  the  bones,  with  the  interposition  of  but 
very  little  subcutaneous  fat.  Hence  it  is  readily  contused  or  excori- 
ated, as,  for  instance,  by  ill-fitting  splints;  and  superficial  gangrene  may 
result  from  slight  pressure,  especially  where  the  circulation  is  impaired 
by  arteriosclerosis.  Thus  I  have  seen  gangrene  of  the  skin  over  the 
malleolus  result  from  pressure  against  the  mattress  in  sleeping,  in  the 
case  of  an  old  gentleman  who  had  previously  lost  a  toe  from  senile 
gangrene.  The  subcutaneous  connective  tissue  is  abundant  only  in  front, 
where  it  readily  allows  considerable  swelling  or  edema,  and  around 
the  tendo  Achillis,  and  only  here  is  there  any  considerable  amount  of 
fat.  The  deep  transverse  fascia  of  the  leg  is  continued  down  behind 
the  tendons  and  vessels  at  the  back  of  the  internal  malleolus.  This 
fascia  and  a  considerable  amount  of  loose  connective  tissue  and  fat 
separate  these  structures  from  the  tendo  Achillis,  so  that  in  the  tenotomy 
of  the  latter  there  is  little  or  no  danger  of  wounding  the  posterior  tibial 
vessels. 

The  Deep  Fascia. — The  deep  fascia,  continuous  with  that  of  the  leg 
above  and  the  foot  below,  is  re-inforced  in  front  and  laterally  so  as  to 
form  firm  bands,  known  as  annular  ligaments,  which  bind  down  and 
keep  in  place  the  tendons  in  these  situations.  There  are  two  anterior 
annular  ligaments,  of  which  the  upper  passes  transversely  between  the 
anterior  borders  of  the  tibia  and  fibula  and  keeps  in  place  the  anterior 
tendons  in  the  slender  lower  third  of  the  leg.  The  lower  band  begins 
on  the  outer  side  of  the  calcaneum  and  splits  into  two  layers,  which  pass 
one  behind  and  one  in  front  of  the  tendons  of  the  peroneus  tertius  and 
extensor  longus  digitorum  and  then  unite  at  the  inner  border  of  the 
latter.  It  again  divides  into  two  branches,  of  which  the  upper  goes  to 
the  front  of  the  internal  malleolus,  the  lower  to  the  scaphoid  and  the 
planter  fascia.  This  ligament  binds  doivn  the  tendons  at  the  bend  of  the 
ankle  and  prevents  them  from  projecting  forward  when  in  action.  The 
lateral  annular  ligaments  connect  the  back  of  the  malleoli  with  the  cal- 
caneum  on  the  corresponding  side  and  prevent  the  dislocation  forward  of 
the  tendons  behind  these  two  malleoli.  As  the  result  of  violence  these 
lateral  bands  may  be  ruptured,  allowing  one  or  more  tendons  to  be  dis- 

located  forward  onto  the  fronl  of  the  corresponding  malleolus.  This 
bag  happened  to  the  tibialis  posticus  and  peroneus  longus,  and  the  latter 

is  more  often  displaced  than  any  tendon  in  the  body,  owing  to  the 
lhallownesa  of  the  groove,  the  weakness  of  the  external  lateral  liga- 
ment,  the  length   of  the  slender  tendon,  and   the  sudden  change  in   its 

direction  below  the  malleolus.     Prom  the  deep  surface  of  the  internal 

annular  ligament  proce  I  pass  forward  to  bony  ridges  at  the  back 
of   the    malleolus    and    the   lower  end   of   the    tibia,   thus   forming  scpu- 


534  THE  LOWER  EXTREMITY 

rate  compartments  for  each  of  the  three  tendons  here.  Thus  it  happens 
that  the  tibialis  posticus  tendon  may  be  displaced  without  the  other  two, 
which  are  farther  from  the  inner  surface  of  the  malleolus. 

In  passing  beneath  the  two  lateral  and  the  lower  anterior  annular 
ligament  the  tendons  are  provided  with  separate  synovial  sheaths,  except 
that  there  is  a  common  sheath  for  the  two  peroneal  tendons  and  for 
those  of  the  extensor  longus  digitorum  and  the  peroneus  tertius.  The 
synovial  sheath  of  the  tibialis  anticus  extends  from  5  to  6  cm.  (2  to  2\  in.) 
above  the  ankle  joint  nearly  to  the  first  metatarsal  bone;  that  of  the  pero- 
neal tendons  from  3  to  4  cm.  (\\  to  If  in.)  above  the  joint  to  the  calcaneo- 
cuboid joint;  that  of  the  extensor  longus  digitorum  and  peroneus  tertius 
from  2  cm.  (f  in.)  above  to  4  to  5  cm.  (If  to  2  in.)  below  the  joint; 
that  of  the  extensor  longus  hallucis  from  1  cm.  %  in.)  above  the  joint 
nearly  to  the  metatarsus;  that  of  the  tibialis  posticus  from  5  cm.  (2  in.) 
above  the  inner  malleolus  to  the  scaphoid,  and  that  of  the  flexor  longus 
digitorum  from  3  cm.  (1-jL  in.)  above  the  malleolus  to  the  sole  of  the 
foot,  where  it  is  crossed  by  the  flexor  longus  hallucis  and  communicates 
with  its  sheath.  These  synovial  sheaths  may  become  inflamed  and  filled 
with  fluid,  and,  as  at  the  wrist,  this  inflammation  is  apt  to  be  tuberculous, 
with  or  without  the  formation  of  "rice  bodies."  I  have  removed  a  large 
mass  the  size  of  an  egg,  due  to  tuberculous  inflammation  of  the  entensor 
tendons  in  front  of  the  ankle.  The  long  tumor,  due  to  an  effusion  into 
one  of  these  synovial  sheaths,  is  often  constricted  where  it  passes  beneath 
the  annular  ligament.  Its  long  vertical  shape  helps  to  differentiate 
it  from  the  more  horizontal  swelling  of  ankle-joint  disease.  Inflam- 
mation of  the  sheath  of  the  tibialis  posticus  may  extend  to  the  ankle  joint 
with  which  it  is  in  close  relation. 

Beneath  the  extensor  tendons  one  finds  a  second  layer  of  fascia  which 
separates  them  from  the  ankle  joint  and,  farther  forward,  covers  the 
extensor  brevis  digitorum  muscle.  The  dorsalis  pedis  artery  and 
the  accompanying  anterior  tibial  nerve  lie  beneath  this  second  layer  of 
fascia,  which  must  be  divided  to  reach  them.  In  sprains,  fractures, 
and  dislocations  of  the  ankle  these  synovial  sheaths  are  apt  to  be  torn 
and  filled  with  effused  blood,  and  the  long-abiding  stiffness  after  such 
injuries  is  in  part  due  to  these  injuries  of  the  sheaths  and  the  result- 
ing adhesions.  Of  the  tendons  about  the  ankle  the  tendo  Achillis  and 
the  peroneal  tendons  are  quite  subject  to  contracture,  the  extensor  tendons 
less  so,  and  the  tendons  behind  the  internal  malleolus  still  less.  These 
contractures  of  the  tendons  lead  to  various  deformities  of  position  of 
the  foot,  known  as  club  foot,  and  the  affected  tendons  require  division 
(tenotomy)  to  correct  the  deformity.  The  rupture  and  tenotomy  of 
the  tendo  Achillis  has  already  been  described  (p.  528).  The  tibialis 
posticus  tendon  may  be  divided  (a)  5  cm.  (2  in.)  above  the  internal  mal- 
leolus, which  is  just  above  its  synovial  sheath  and  where  the  tendon  is 
farther  from  the  artery  than  below.  The  knife  is  entered  close  to  the 
inner  border  of  the  tibia.  (&)  It  may  be  divided  a  little  below  and 
in  front  of  the  inner  malleolus,  between  the  internal  annular  ligament 
and  the  scaphoid  bone.     The  tibialis  anticus  may  be  divided  at  the  latter 


PLATE  LVI 


FIG.   183 


The  Internal  Annular  Ligament  of  the  Ankle  and  the  Arti- 
ficially Distended  Synovial  Membranes  of  the  Tendons  which 
it  Confines.     (Gerrish,  after  Testut.) 


FIG.   184 


The  External  Annular  Ligament  of  the  Ankle  and  the  Arti- 
ficially Distended  Synovial  Membranes  of  the  Tendons  which 
it  Confines.     (Gerrish,  alter-  Testut.; 


PLATE  LVII 


FIC.   185 


Pott's  Fracture  by  Abduction,  two  months  after  the  injury. 


FIG.    186 


Ankle  Joint.     Anteroposterior  cava  somewhat  from  above. 
Mnle,  aged  twenty-three  years. 


THE  ANKLE  535 

level  with  the  posticus,  or  a  little  above  its  insertion  into  the  internal 
cuneiform.  The  tendon  of  a  paralyzed  muscle  may  be  joined  to  that  of  a 
sound  one  (tendon  grafting)  to  prevent  a  deformity  and  restore  certain 
movements  of  the  foot.  The  tendons  of  the  ankle  are  not  infrequently 
ruptured  through  violence,  especially  the  tendo  Achillis. 

Bursa. — A  bursa  is  situated  between  the  tendo  Achillis  and  the  os 
calcis,  rising  about  12  mm.  (|  in.)  above  the  latter.  When  inflamed 
it  bulges  on  either  side  of  the  tendon,  effacing  the  depressions  which 
normally  exist  there.  Such  inflammation,  due  to  excessive  walking, 
an  injury,  or  a  badly  fitting  shoe,  may  simulate  ankle-joint  disease  and, 
if  suppurative,  lead  to  caries  of  the  os  calcis.  Pain  is  caused  by  flexion 
or  extension  of  the  foot  or  contraction  of  the  calf  muscles.  Bursse  may 
develop  from  pressure  over  the  malleoli,  especially  the  external,  as  in 
tailors  who  sit  cross-legged  ("tailor's  bursa"). 

The  dorsalis  pedis  artery,  from  its  superficial  position,  is  frequently 
divided  in  wounds  or  ruptured  in  severe  contusions,  while  the  posterior 
tibial  is  well  protected  from  injury  by  the  prominent  malleolus,  the 
neighboring  tendons,  and  the  annular  ligament.  The  dorsalis  pedis 
artery  may  be  compressed  against  the  underlying  bones  and  its  pulsation 
may  be  sought  for,  to  determine  the  condition  of  the  artery  and  of  the 
circulation,  in  senile  gangrene  and  in  suscepted  embolism  at  the  bifur- 
cation of  the  popliteal. 

The  Ankle  Joint. — The  ankle  joint  owes  its  strength  to  the  strength 
of  the  lateral  ligaments  and  the  many  closely  applied  tendons,  as  well 
as  to  the  mortise  and  tenon  shape  of  the  bony  surfaces.  The  anterior 
and  posterior  ligaments  are  unimportant  and  so  thin  that  effusion, 
when  it  occurs  within  the  joint,  is  first  noticeable  in  front  as  a  fluctuating 
bulging,  beneath  the  extensor  tendons  and  especially  on  either  side  of 
diem,  in  front  of  the  malleoli.  This  bulging  is  the  more  marked  because 
the  synovial  membrane  forms  somewhat  of  a  pouch  anteriorly  and  pos- 
teriorly. The  bulging  in  front  of  the  external  malleolus  is  the  best  point 
to  open  or  inject  the  joint.  When  the  effusion  is  more  marked  it  may  be 
evident  behind,  as  a  bulging  of  the  posterior  part  of  the  capsule,  which 
gives  rise  to  fluctuation  on  either  side  of  the  tendo  Achillis. 

The  ankle  joint  proper  is  a  true  hinge  joint  and  normally  allows 
no  lateral  motion,  except  passively  in  extreme  extension  (plantar  flexion) 
when  the  narrowest  part  of  the  upper  surface  of  the  astragalus  is  in  the 
widest  part  of  the  tibiofibular  mortise.  The  ankle  should  be  tested  for 
lateral  mo/ion  with  the  foot  flexed  nearly  to  a  right  angle,  care  being 
taken  to  grasp  the  astragalus,  and  not  the  calcaneum,  by  the  thumb 
and  fingers  directly  below  and  in  front  of  the  two  malleoli.  If  the  foot  is 
grasped  a  little  lower,  over  the  calcaneum,  lateral  motion  is  obtained 
between  the  astragalus  and  calcaneum.  Lateral  movement  at  the  ankle 
joint  indicates  disease  or  injur;/  of  the  joint.  On  account  of  its  super- 
ficial ;iikI  exposed  position,  inflammation  of  the  ankle  joint  QOt  nneom- 
monly  results  from  injury,  exposure  to  cold  and  wet,  etc.  As  the 
position  of  the  joint  does  not  affect  its  capacity,  and  the  flexor  and 
•  n  <>i   muscles  about   balance  one  another,  the  foot   does  not  assume 


536  THE  LOWER  EXTREMITY 

any  characteristic  position  when  the  ankle  is  inflamed.  Later  the  calf 
muscles  aided  by  gravity  and  the  pressure  of  the  bedclothes  induce 
plantar  flexion,  causing  "pointing"  of  the  toes. 

Sprains  of  the  ankle  are  common,  as  the  weight  of  the  whole  body, 
acting  through  the  leverage  of  the  entire  lower  extremity  in  inversion 
or  eversion  of  the  ankle,  tends  to  lacerate  fibers  of  one  of  its  lateral  liga- 
ments and  strain  some  of  the  tendons.  Landerer  has  expressed  the 
opinion  that  95  per  cent,  of  so-called  sprains  are  fractures.  This  is 
probably  literally  true  if  we  count  as  fractures  those  cases  where,  instead 
of  a  tear  of  the  ligament,  a  small  portion  of  bone  is  avulsed  at  its  attach- 
ment. 

The  ankle  joint  may  be  dislocated  so  that  the  foot  is  displaced  back- 
ward, forward,  inward,  or  outward.  Only  the  anteroposterior  forms 
are  pure  dislocations,  the  lateral  forms  being  almost  always  associated 
with  fracture  of  one  or  both  bones  of  the  leg  at  the  ankle. 

Dislocation  of  the  Foot  Backward. — Dislocation  of  the  foot  back- 
ward is  usually  due  to  extreme  plantar  flexion  and  the  establishment  of 
a  new  centre  of  motion  between  the  posterior  border  of  the  tibial  facet 
and  the  posterior  lip  of  the  astragalus,  so  that  continued  movement 
ruptures  the  lateral  and  anterior  ligaments,  and  then  the  foot  is  pushed 
backward  or  the  tibia  forward  as  the  plantar  flexion  is  corrected.  It 
may  also  be  due  to  great  force  applied  to  either  the  foot  or  the  leg  while 
the  other  is  fixed.  It  is  resisted  by  (1)  the  shape  of  the  upper  articular 
facet  of  the  astragalus  and  of  the  tibiofibular  mortise,  which  are  nearly 
one-fourth  narrower  behind  than  in  front;  (2)  the  increase  of  width  from 
behind  forward  between  the  lateral  facets  of  the  astragalus;  (3)  the  lower 
level  of  the  articular  surface  of  the  tibia  behind  than  in  front;  and  (4) 
the  re-inforcement  of  the  posterior  ligament  by  the  flexor  longus  pollicis 
tendon.  The  foot  appears  shortened  in  front,  where  the  lower  end  of 
the  tibia  projects  prominently  and  rests  upon  the  scaphoid  and  cuneiform 
bones,  and  the  extensor  tendons  may  be  felt  as  tense  cords.  The  heel 
is  lengthened,  exaggerating  the  depressions  on  the  sides  of  the  tendo 
Achillis,  which  curves  markedly  backward.  As  a  result  of  fracture  of 
the  ankle  by  eversion,  partial  and  even  complete  backward  dislocations 
are  not  infrequent,  but  pure  dislocations  of  this  kind  are  rare.  Forward 
dislocation  is  still  more  rare,  for,  though  the  anatomical  factors 
which  resist  backward  dislocation  favor  this  form,  the  weight  of  the 
body  or  the  external  force  and  counterforce  are  rarely  brought  forcibly 
upon  the  ankle  in  the  proper  direction  to  produce  it.  The  mode  of 
production  and  the  deformity  of  the  foot  are  the  reverse  of  the  last 
variety. 

Two  forms  of  dislocation  inward  are  observed :  In  one  the  foot  is  much 
inverted,  so  that  the  upper  surface  of  the  astragalus  can  be  felt  and  seen 
as  a  prominence  below  the  outer  malleolus;  in  the  other  there  is  less 
or  no  inversion,  but  the  foot  is  much  adducted,  so  that  the  toes  may  even 
point  directly  inward.  The  latter  form  may  be  secondary  to  a  back- 
ward dislocation.  Many  cases  belong  to  the  group  of  fractures  of  the 
ankle  by  inversion, 


THE  ANKLE 


537 


The  so-called  outward  dislocations  represent  the  deformity  in  cases 
of  Pott's  fracture  (fracture  by  eversion). 

Fractures  of  the  Bones  of  the  Leg  just  above  the  Ankle. — 
Fractures  of  the  bones  of  the  leg  just  above  the  ankle  are  produced 
by  eversion  or  inversion  of  the  foot,  aided  somewhat  by  the  weight  of  the 
body.  Both  eversion  and  inversion  produce  fractures  which  are  very 
similar.  In  reference  to  these  fractures  it  should  be  remembered  that  the 
tibia  and  fibula  are  very  strongly  bound  together  at  their  inferior  articular 


Fig.  187 


Fig.  188 


Diagram  of  fracture  by  aversion  of  the 
ankle,  showing  the  fractures  of  the  two 
bones. 


Diagram  of  fracture  by  inversion  of  the 
ankle.  Fracture  of  the  fibula  only  is  repre- 
sented and  at  two  levels.  The  dotted  linen 
show  a  fracture  of  the  fibula  some  distance 
above  the  malleolus,  the  continuous  lines 
a   fracture  at    the  base  of  the  malleolus. 


lion,  and  thai  this  point  serves  as  the  fulcrum  of  a  lever  for  the  fibula,  of 

which  the  external  malleolus  represents  (Ik-  short  arm  and  the  fibula 

above  the  joint    the   long  arm. 

Fractures  by  Eversion  and  Abduction.     In  fractures  by  eversion 
and  abduction  (Pott's  fracture)  (Fig.  1ST)  the  strain  first  comes  on  the 

internal  lateral  ligament,   which    may   (ear,   but,    owing   to   its  strength, 

usually  tears  off  the  internal  malleolus  at  its  base.    This  allowa  the 
further  eversion  of  the  foot,  and  the  astragalus  then  presses  the  external 


538  THE  LOWER  EXTREMITY 

malleolus  outward.  This  is  resisted  by  the  strong  ligaments  of  the 
inferior  tibiofibular  joint,  which  suffer  violence  in  the  shape  of  partial 
rupture  or  sprain,  but  usually  hold  the  bones  together,  so  that  the  strain 
comes  upon  the  long  arm  of  the  lever,  the  shaft  of  the  fibula,  which 
breaks  2.5  to  7.5  cm.  (1  to  3  in.)  above  the  malleolus.  The  upper 
end  of  the  lower  fragment  of  the  fibula  is  displaced  toward  the  tibia. 
The  foot,  with  the  outer  malleolus,  is  displaced  outward,  and  often  some- 
what backward,  and  everted,  the  inner  malleolus,  or  the  lower  end  of  the 
fractured  tibia,  is  very  prominent  and  may  cause  the  laceration  of  the 
taut  overlying  skin.  The  characteristic  features  are  (1)  lateral  mobility, 
due  to  the  essential  lesion,  the  tibiofibular  diastasis,  and  the  consequent 
widening  of  the  mortise,  and  to  the  fracture  of  the  internal  malleolus 
and  of  the  fibula  above  its  malleolus;  and  (2)  three  points  of  tenderness — 
(a)  in  front  of  the  tibiofibular  joint,  in  the  groove  between  the  tibia  and 
the  external  malleolus,  (6)  over  the  base  or  anterior  border  of  the  internal 
malleolus,  and  (c)  over  the  fibula  just  above  the  malleolus,  or  2.5  to 
5  cm.  (1  to  2  in.)  higher. 

In  fractures  due  to  forcible  inversion  (Fig.  188)  the  external  lateral 
ligament  first  feels  the  strain.  If  simply  the  ligament  partly  gives  way  a 
sprain  may  result,  unless  the  action  of  the  force  continues.  If  the  liga- 
ment holds,  and  it  commonly  does,  it  pulls  the  tip  of  the  external  malle- 
olus inward,  which  forces  the  long  arm  of  the  fibular  lever  outward, 
until  it  breaks  close  above  the  malleolus,  or  still  higher,  or  at  the  epiphy- 
seal line  in  the  young.  The  force  continuing  inverts  the  foot  still  farther 
and  the  astragalus  presses  against  the  internal  malleolus  and  breaks 
off  the  latter  or  a  larger  portion  of  the  lower  end  of  the  tibia,  the  line  of 
fracture  passing  obliquely  upward  and  inward  through  the  tibia  from  its 
articular  surface.  The  lateral  mobility  and  the  three  points  of  tenderness 
are  present  in  this  form,  but  perhaps  not  so  markedly,  as  there  is  less 
and  may  be  no  injury  at  the  lower  tibiofibular  joint.  In  this  form  the 
injury  may  stop  short  with  fracture  of  the  fibula,  no  injury  of  the  internal 
malleolus  or  internal  ligament  resulting.  In  fractures  by  inversion  the 
upper  end  of  the  lower  fragment  of  the  fibula  is  displaced  outward, 
unless  it  is  held  by  the  untorn  periosteum.  To  determine  the  presence 
and  the  point  of  fracture  of  the  fibula  an  excellent  way  is  to  press  inward 
on  the  tip  of  the  malleolus,  the  short  arm  of  the  lever,  which  forces  the 
upper  end  of  the  lower  fragment  to  tilt  outward  and  causes  a  false  point 
of  motion,  or  at  least  a  point  of  tenderness,  to  appear  at  this  point. 

Owing  to  the  frequency  of  these  two  classes  of  fractures  and  the  dis- 
ability following  improper  treatment,  they  should  be  carefully  reduced 
and  treated.  It  is  especially  important  to  correct  the  lateral  displacement 
and  the  eversion,  otherwise  the  gait  is  painful  and  imperfect,  for  the 
weight  of  the  body  then  falls  too  far  to  the  inner  side  of  the  foot,  so  that 
a  strain  is  brought  upon  the  internal  lateral  ligament  and  a  painful 
flat  foot  is  produced.  If  the  posterior  displacement  is  not  corrected, 
dorsal  flexion  at  the  ankle  is  limited  and  the  patient  must  toe  far  outward 
in  walking  to  avoid  the  necessity  of  dorsal  flexion. 

The  lower  epiphysis  of  the  tibia  is  more  often  separated  than  the  upper. 


THE  FOOT  539 

The  fibula  is  usually  broken  at  the  same  time  at  a  higher  level,  though 
its  epiphysis,  which  reaches  to  the  level  of  the  tibial  articular  surface, 
is  sometimes  separated  in  place  of  a  fracture  of  the  shaft.  The  lower 
epiphysis  of  the  tibia  includes  the  malleolus  and  the  articular  surface, 
and  unites  in  the  nineteenth  year;  the  loiver  epiphysis  of  the  fibula 
includes  the  outer  malleolus  to  the  upper  limit  of  its  articular  facet  for 
the  astragalus,  and  unites  about  the  twenty-first  year.  Both  epiphyseal 
lines  are  horizontal  and  are  in  close  relation  mesially  with  the  synovial 
membrane,  which  extends  up  between  the  two  bones.  They  are  sep- 
arated from  the  synovial  membrane  by  the  periosteum,  which  continues 
over  them,  so  that  the  membrane  usually  escapes  injury.  Arrest  of 
growth  of  the  tibia  may  occur  and  this  is  followed  by  inversion  of  the 
foot,  on  account  of  overgrowth  of  the  fibula. 

Excision  of  the  ankle  is  rarely  done  for  injury  and  not  often  for  tubercu- 
lous disease.  Symes'  or  Pirogoff's  amputation  often  gives  a  better  result. 
Arthrectomy  often  gives  good  results.  Bilateral  incisions  are  usually 
made  over  the  front  of  the  malleoli;  curving  forward  over  the  foot  in 
such  a  way  as  to  lie  between  the  tendons  in  front  and  those  behind  the 
malleoli.  Konig  chisels  away  the  attachments  of  the  lateral  ligaments 
to  the  malleoli  to  spare  the  ligaments.  Removal  of  the  astragalus 
greatly  facilitates  the  free  access  to  all  parts  of  the  joint  and  a  thorough 
arthrectomy.  In  such  cases  it  is  better  to  divide  the  ligaments  and 
spare  the  malleoli,  especially  in  young  subjects,  owing  to  the  proximity 
of  the  latter  to  the  epiphyseal  lines.  Lauenstein  uses  a  single  long  ex- 
ternal incision,  Kocher  a  curved  oblique  external  incision,  and  both  of 
the  latter  then  retract  the  peroneal  tendons  backward,  divide  the  external 
lateral  ligaments,  and  fully  supinate  (invert)  the  foot,  so  as  to  expose 
both  articular  surfaces. 

THE   FOOT. 

Landmarks  and  Surface  Markings.— Along  the  outer  border  of 
the  foot  nearly  the  entire  outer  surface  of  the  calcaneum  is  subcuta- 
neous, and  we  can  feel  its  external  tubercle  and  its  peroneal  tubercle, 
the  latter  less  than  2.5  cm.  (\  in.)  below  and  a  little  in  front  of  the  tip  of 
the  malleolus.  The  short  peroneal  tendon  is  above,  the  long  one  below 
it.  Midway  between  it  and  the  external  malleolus  is  the  calcaneo- 
BStragaloid  joint.  The  tuberosity  of  the  base  of  the  fifth  metatarsal 
bone  is  the  most  prominent  landmark  on  this  border,  and  can  be  felt 
under  all  conditions  of  swelling,  etc.,  about  6  cm.  Cl\  in.)  in  front  of  the 
malleolus.     The    cuboid    extends    tor  2.5  em.    (1    in.)  or  so  behind  it, 

hence  die  calcaneocuboid    (mediotarsal)  joint    is  a   little  more  than 

midway  between   the  tip  of  the  external   malleolus  and   the  tubercle  of 

th<-  fifth  metatarsal.     Along  the  inner  border  of  the  foot  we  can  feel  the 

internal  tubercle  of  the  c;dcanciim  ;  the  sustentaculum  tali,  2.5  em.  (I  in.) 
below  the  internal  malleolus;  the  head  of  the  astragalus,  prominent 
in  flat  foot,  1 1  to  IS  mm.  (\  to  ]  in.)  in  front  of  the  sustentaculum;  the 
tuberosity  of  the  sen  phnid ',   abouj    3  em.   f  I  |   in.)  in  front    of   the  snsten- 


540  THE  LOWER  EXTREMITY 

taculum,  the  space  between  the  two  being  occupied  by  the  inferior 
calcaneoscaphoid  ligament  and  the  tibialis  posticus  tendon;  the  base 
and  head  of  the  first  metatarsal  bone,  and  the  sesamoid  bones  on  the 
plantar  surface  of  the  latter.  The  calcaneo-astragaloid  joint  lies  directly 
above  the  sustentaculum,  and  the  first  metatarsophalangeal  joint  a 
little  distal  to  the  middle  of  the  ball  of  the  great  toe.  The  tuberosity  of 
the  scaphoid  is  the  best  landmark  on  the  inner  border,  and  can  be  felt 
even  when  the  foot  is  much  swollen.  In  such  conditions  the  head  of 
the  metatarsal  bone  is  not  plainly  palpable,  hence  it  is  well  to  know 
that  the  first  tarsometatarsal  articulation  is  3.5  cm.  (1-|  in.)  in  front  of  the 
tuberosity  of  the  scaphoid  and  2  cm.  (|-  in.)  in  front  of  the  line  drawn 
transversely  across  the  foot  from  the  tubercle  of  the  base  of  the  fifth 
metatarsal  bone,  or  the  fifth  tarsometatarsal  articulation. 

Topography. — The  mediotarsal  joint,  i.  e.,  the  joint  between  the  astrag- 
alus and  calcaneum  posteriorly  and  the  scaphoid  and  cuboid  anteriorly, 
commences  internally  just  behind  the  scaphoid  tuberosity  and  externally 
a  little  anterior  to  the  mid-point  between  the  tip  of  the  external  malleous 
and  the  tubercle  of  the  fifth  metatarsal  bone.  The  joint  line  is  trans- 
verse with  a  slight  sinuosity,  convex  forward  internally  and  concave 
forward  externally.  The  position  of  the  first  tarsometatarsal  joint  has 
already  been  indicated,  that  of  the  fifth  lies  just  behind  the  prominent 
tubercle  of  the  fifth  metatarsal  bone.  The  tarsometatarsal  joint  line, 
between  these  two  ends,  is  interrupted  by  the  mortising  of  the  second 
metatarsal  bone  between  the  internal  and  external  cuneiform  bones.  The 
line  of  its  articulation  with  the  middle  cuneiform  is  1  cm.  (■§-  in.)  behind 
that  of  the  first  tarsometatarsal  joint.  The  metatarsophalangeal  articula- 
tions are  about  2.5  cm.  (1  in.)  behind  the  webs  between  the  corresponding 
toes,  the  proximal  and  part  of  the  middle  phalanges  being  buried  in  the 
web. 

On  the  outer  part  of  the  dorsum  of  the  foot  the  fleshy  mass  of  the 
extensor  brevis  digitorum  can  be  felt  beneath  the  tendons  of  the  exten- 
sor longus  digitorum,  where  it  can  be  seen  when  in  action.  It  fills  the 
gap  between  the  front  of  the  astragalus  and  the  calcaneum.  The 
course  of  the  dorsalis  pedis  artery  has  been  given  above  (see  p.  532); 
it  is  crossed  by  the  inner  tendon  of  the  extensor  brevis  muscle,  and 
rests  on  the  head  of  the  astragalus,  the  dorsum  of  the  scaphoid,  and  the 
interval  between  the  middle  and  internal  cuneiform  bones. 

The  plantar  arteries  start  at  the  bifurcation  of  the  posterior  tibial, 
midway  between  the  inner  malleolus  and  the  inner  border  of  the  heel. 
Thence  the  smaller  branch,  the  internal  plantar,  follows  a  line  to  the 
middle  of  the  plantar  surface  of  the  great  toe.  The  course  of  the  exter- 
nal plantar  is  obliquely  across  the  sole  to  a  point  a  little  internal  to  the 
base  of  the  fifth  metatarsal  bone,  and  thence  obliquely  inward  across 
the  bases  of  the  metatarsal  bones,  which  are  covered  by  the  interossei,  to 
the  proximal  end  of  the  first  interosseous  space,  where  its  arch  is  com- 
pleted by  anastomosing  with  the  communicating  branch  of  the  dorsalis 
pedis.  By  means  of  this  arch  the  anterior  and  posterior  tibial  arteries 
anastomose.     In  wounds  of  the  plantar  arch,  which  are  serious  on 


THE  FOOT 


541 


account  of  its  depth  beneath  many  important  structures,  the  ligature 
of  both  tibial  vessels,  at  or  just  above  the  ankle,  would  not  arrest  the 
hemorrhage  without  fail,  for  the  peroneal  artery  would  bring  blood  to 
the  arch  through  (1)  the  anastomosis  of  the  anterior  peroneal  with  the 


Fig.  189 


TIBIALIS  ANTICUS 
MUSCLE 


INTERNAL 
SAPHENOUS   VEIN 


INTERNAL       / 
SAPHENOUS    NERVE ' 


ANTERIOR  TIBIAL 
NERVE 


OORSALIS    PEDIS     /  fex'    J 
ARTERY 


MUSCULO -CUTANEOUS 
NERVE 


EXTERNAL 
SAPHENOUS   VEIN 


EXTENSOR     COMMUNIS 
DIGITORUM    MUSCLE 


EXTERNAL 
SAPHENOUS   NERVE 


PERONEUS  TERTIUS 
USCLE 


I  >01     i]    vii-w  of  fool   :mc|   : 1 1 1 k  1  < • . 


externa]  plantar  artery,  (2)  the  anastomo  \a  of  the  posterior  peroneal 
with  the  internal  calcaneal  branch  of  the  posterior  tibial,  and  (li)  the 
anastomoses  of  both  of  these  peroneal  branches  with  the  tarsal  and  meta- 
tarsal branches  of  die  dor  ali  pedis.  In  fact,  however,  elevation  and 
ire  will  check  mo  t  hemorrhages  of  the  foot 


542  THE  LOWER  EXTREMITY 

The  Skin.— The  skin  of  the  dorsum  and  inner  aspect  of  the  foot  is  thin 
and  movable,  that  of  the  sole  is  dense  and  thick  where  it  normally  comes 
in  contact  with  the  ground,  i.  e.,  under  the  heel,  the  outer  border,  and 
the  distal  ends  of  the  metatarsal  bones.  The  skin  on  the  dorsum  is 
readily  excoriated,  and  the  lack  of  fatty  tissue  or  muscle  between  it  and 
the  skeleton  of  the  foot  makes  it  very  liable  to  gangrene  from  the  pressure 
of  splints,  dressings,  etc.,  or  from  contusions.  The  skin  of  the  foot 
becomes  thick  and  callous  wherever  it  is  exposed  to  undue  pressure,  and 
the  callosities  often  become  painful  when  pressed  upon.  Beneath  the 
abnormal  thickenings  bursa  may  develop. 

The  subcutaneous  tissue  on  the  dorsum  is  lax  and  abundant,  so  that 
great  swelling  occurs  from  inflammation;  and  edema  and  general 
dropsy  are  often  first  evident  here.  This  tissue  is  very  thick  and  dense 
on  the  sole,  connecting  the  skin  closely  with  the  fascia  and  enclosing  the 
fat  in  little  spaces,  as  in  the  palm  and  the  scalp.  Hence  the  skin  of  the 
sole  does  not  gape  on  being  incised,  so  that  exploratory  incisions  must 
be  longer  than  otherwise  and  strongly  retracted,  to  expose  foreign  bodies, 
etc.  It  is  most  abundant  on  those  parts  of  the  sole  where  the  pressure 
is  greatest,  and  in  those  who  walk  most,  and  may  even  reach  2  cm.  in 
thickness  beneath  the  heel,  so  that  it  forms  a  veritable  cushion  that 
must  diminish  the  effect  of  contusions  and  falls.  Owing  to  its  density 
inflammation  in  it  extends  with  difficulty  and  can  produce  little  swelling 
but  much  pain,  especially  as  the  skin  of  the  sole  is  well  supplied  with 
nerves  and  is  very  sensitive,  much  more  so  than  that  of  the  dorsum. 

In  the  subcutaneous  tissue  on  the  dorsum  many  superficial  veins  are 
visible.  They  form  an  arch,  concave  toward  the  ankle,  from  the  ends 
or  sides  of  which  the  internal  and  external  saphenous  veins  arise.  In 
varicose  veins  of  the  leg  these  veins  of  the  dorsum  are  often  involved. 
The  internal  and  external  saphenous  and  the  musculocutaneous  nerves 
are  in  the  same  subcutaneous  layer.  ''Perforating  ulcer,"  a  peculiar 
affection,  occurs  generally  at  the  points  of  pressure  on  the  sole,  and  is 
often  attributed  to  arteriosclerosis,  diabetes,  or  trophic  disturbances  in 
certain  nerve  lesions,  like  locomotor  ataxia,  etc.  It  appears  usually  as 
a  sinus  leading  to  bone,  into  a  joint,  or  through  to  the  dorsum,  and 
often  heals  with  rest.  After  healing  all  pressure  must  be  removed  from 
the  scar  of  the  "ulcer." 

The  Fascia  of  the  Dorsum. — The  fascia  of  the  dorsum  consists 
of  two  layers;  the  more  superficial  one  is  continuous  with  the  annular 
ligaments  and  covers  the  long  tendons;  the  deeper  forms  a  sheath  for 
the  extensor  brevis  muscle  and  covers  the  dorsalis  pedis  artery.  They 
are  thin  and  of  no  surgical  importance.  On  the  contrary,  the  deep  fascia 
of  the  sole  or  plantar  fascia  is  very  important  and,  like  the  palmar  fascia, 
consists  of  three  parts,  a  dense  strong  central  portion  and  two  thinner 
lateral  portions.  The  outer  portion  is,  however,  very  strong  and  forms 
a  firm  band  between  the  calcaneum  and  the  fifth  metatarsal  bone. 
The  central  portion  is  stretched  like  a  bowstring  between  the  two  ends  of 
the  longitudinal  arch  of  the  foot,  the  inner  tuberosity  of  the  calcaneum, 
and  the  heads  of  the  metatarsal  bones,  where  it  divides  into  slips  for  the 


THE  FOOT  543 

toes  similar  to  those  for  the  fingers  in  the  hand.  Hence  the  plantar  fascia, 
especially  its  central  portion,  is  an  important  factor  in  maintaining  the 
longitudinal  arch  of  the  foot,  the  sinking  of  which,  in  flat  foot,  necessi- 
tates a  marked  yielding  of  this  fascia.  Talipes  cavus,  in  which  the  arch 
is  much  raised,  depends  largely  or  entirely  upon  a  contraction  of  this 
fascia.  In  this  condition  and  in  talipes  varus,  in  which  this  fascia  is 
often  contracted  and  the  arch  correspondingly  raised,  the  fascia  is 
divided  subcutaneomly  by  a  tenotome  to  cure  the  deformity.  This  divi- 
sion is  best  made  about  2.5  cm.  (1  in.)  in  front  of  its  posterior  attachment 
to  the  internal  calcaneal  tuberosity,  in  its  narrowest  part,  where  the  knife, 
entered  from  the  inner  side,  is  behind  the  external  plantar  artery.  This 
fascia  bears  the  same  relation  to  inflammation  and  abscess  as  the  palmar 
fascia  in  the  hand,  resisting  their  extension  toward  the  sole.  Similarly 
two  intermuscular  septa  pass  from  its  deep  surface,  where  it  joins  the 
lateral  portions,  to  the  plantar  aspect  of  the  bones  and  the  interosseous 
fascia.  Three  muscidar  compartments  are  thus  formed,  of  which  the 
central  one  is  the  larger  and  deeper  and  contains  the  majority  of  the 
muscles  and  tendons  and  the  plantar  vessels  and  nerves.  These  inter- 
muscular septa  are  too  feeble  to  affect  the  course  of  a  deep  plantar 
abscess  to  any  great  extent. 

The  Posterior  Tibial  Nerve.— The  posterior  tibial  nerve  bifurcates 
a  little  above  the  division  of  the  artery.  The  internal  plantar  nerve, 
unlike  the  corresponding  artery,  is  the  larger  of  the  two.  In  its  distri- 
bution the  internal  plantar  nerve  corresponds  closely  with  that  of  the 
median  in  the  hand,  the  external  plantar  with  the  ulnar. 

The  Bursa. — The  bursa  in  the  subcutaneous  tissue  over  the  first 
metatarsophalangeal  joint,  when  enlarged,  constitutes  a  bunion.  This 
is  usually  associated  with  a  deformity  of  the  great  toe  {hallux  valgus), 
generally  due  to  improperly  shaped  or  too  short  shoes,  which  force  the 
great  toe  outward  and  render  its  metatarsophalangeal  joint  very  promi- 
nent internally.  The  internal  lateral  ligament  becomes  lengthened  and 
the  overlying  skin  becomes  thickened  and  indurated,  and  the  bursa, 
pressed  between  this  thickening  and  the  projecting  bone,  often  becomes 
inflamed.  If  it  suppurates  it  often  opens  both  superficially  and  into 
the  joint,  which  hitter  then  becomes  disorganized  and  requires  resection. 
Resection  is  also  employed  to  cure  the  deformity  and  the  resulting 
bunion.  In  this  operation  it  must  be  remembered  thai  the  outwardly 
displaced  extensor  tendon  of  the  toe  and  the  outer  part  of  the  fibrous 
capsule  of  the  joint  have  probably  both  become  contracted  and 
shortened.  Then-  is  often  a  considerable  overgrowth  <>f  the  distal 
end  of  the  metatarsal  bone  on  its  inner  side,  which  musi  be  removed 
to  traighten  the  toe.  Flal  fool  tends  to  produce  a  bunion  by  pressure 
upon  tins  joint.  This  same  joint  is  selected  with  singular  unanimity 
;i    the   ole  or  principal  site  of  the  manifestation  of  gout.    This  is  partly 

Owing  t"  the  abundant  fibrous  tissue  at  a  point  where  (he  circulation  is 
slight  and  sluggish,  where  a  good  part  of  the  weight,  is  borne,  and  which 

often  exposed  to  cold  and  damp.    Holden  describes  the  frequenl 

occurrence  of  a  huge  irregular  bursa  between  the  tendons  of  th<'  extensor 


544  THE  LOWER  EXTREMITY 

longus  digitorum  and  the  underlying  prominent  head  of  the  astragalus, 
which  sometimes  communicates  with  the  mediotarsal  joint.  Bursa  may 
develop  almost  anywhere  from  pressure,  as  over  the  points  on  which  the 
foot  rests  in  the  various  forms  of  club  foot,  especially  over  the  cuboid 
in  talipes  equino varus. 

The  numerous  fine  lymphatics  of  the  sole  pass  to  the  borders  of  the 
foot,  especially  the  inner  border,  and  to  the  dorsum,  where  the  main 
lymph  vessels  are  found,  particularly  on  its  inner  side.  Thence  they 
run  along  the  inner  side  of  the  leg  with  the  internal  saphenous  vein, 
and  pass  mostly  to  the  inguinal  nodes.  Some  from  beneath  the  heel  and- 
from  the  posterior  half  of  the  outer  border  of  the  foot  run  up  the  posterior 
surface  of  the  leg,  with  the  short  saphenous  vein,  and  enter  the  popliteal 
nodes.  Hence  in  inflammation  on  the  dorsum  and  inner  border  of  the 
foot  lymphatic  enlargement  will  involve  the  inguinal  nodes,  while  in- 
flammation on  the  outer  border  may  affect  either  the  inguinal  or  popliteal 
nodes,  or  both.  Lymphangitis  most  often  follows  lesions  of  the  dorsum 
and  inner  border. 

The  foot  is  arched  in  two  directions,  longitudinally  and  transversely. 
These  arches  are  due  to  the  shape  of  the  bones,  and  are  maintained  by 
ligaments  and,  to  a  less  extent,  by  the  tendons  and  short  muscles  of 
the  sole.  They  account  for  the  strength  of  the  foot  and  its  relative 
freedom  from  injury,  though  constantly  exposed  to  traumatism. 

The  Longitudinal  Arch. — The  longitudinal  arch,  the  more  important 
of  the  two,  consists  of  two  piers,  on  the  ends  of  which  the  foot  rests,  i.  e., 
the  heel  and  the  heads  of  the  metatarsal  bones.  In  addition,  the  foot  is 
steadied  or  buttressed  by  its  outer  border,  which  broadens  the  surface  of 
contact  with  the  ground.  The  middle  of  the  inner  border  and  the  inner 
part  of  the  sole  are  raised  from  the  ground  by  the  inner  and  more  curved 
portion  of  the  arch,  which  is  thus  known  as  the  instep.  On  account  of 
this  difference  of  the  two  borders  the  arch  is  divided  into  two  parts 
having  a  common  posterior  pillar,  the  calcaneum  and  the  hind  part  of 
the  astragalus.  The  anterior  pillar  of  the  outer  and  flatter  arch  is  formed 
by  the  cuboid  and  the  two  outer  metatarsals;  the  anterior  pillar  of  the 
inner  and  more  curved  arch  is  formed  by  the  head  and  neck  of  the 
astragalus,  the  scaphoid,  cuneiform,  and  three  inner  metatarsals.  The 
inner  division  of  the  arch  bears  most  of  the  weight,  the  outer  division 
steadies  the  foot.  The  anterior  pillars,  composed  of  a  number  of  small 
bones  and  their  joints,  are  very  elastic  and  springy,  giving  the  elasticity  to 
the  gait.  The  posterior  pillar,  consisting  of  only  two  bones,  astragalus  and 
calcaneum,  and  one  joint  of  very  limited  motion,  is  solid  in  order  to 
support  the  greater  part  of  the  weight  of  the  body,  and  inelastic  to  give 
a  firm  attachment  and  leverage  to  the  calf  muscles,  which  elevate  this 
pillar.  The  difference  in  the  two  pillars  is  seen  in  jumping  from  a 
height.  When  we  alight  on  the  heels  the  jar  is  felt  throughout  the 
body,  but  when  we  alight  on  the  ball  of  the  foot  the  elasticity  of  the 
anterior  pillar  of  the  arch  absorbs,  so  to  speak,  all  the  jar.  The 
astragalus,  or  more  especially  its  head,  serves  as  the  keystone  of  the 
arch,  but,  unlike  keystones  in  ordinary  arches,  it  is  not  wedge-shaped, 


THE  FOOT  545 

it  is  mobile  and  it  only  imperfectly  supports  and  receives  support  from 
the  two  pillars. 

The  Transverse  Arch. — The  transverse  arch  is  most  marked  near 
the  tarsometatarsal  joints  and  is  due  to  the  wedge  shape  of  the  bones. 
It  is  continued  with  diminished  curvature  to  the  heads  of  the  metatar- 
sal bones.  It  protects  the  vessels  and  soft  parts  of  the  sole  from  injurious 
pressure  and,  by  its  yielding  in  walking,  etc.,  gives  elasticity  and  spring 
to  the  foot. 

Both  of  the  arches  are  maintained  by  ligaments  and  tendons.  The 
transverse  arch  is  maintained  by  the  transversely  directed  dorsal,  plantar, 
and  interosseous  ligaments,  and  by  the  obliquely  directed  peroneus 
longus  tendon  and,  to  some  extent,  the  expansion  of  the  tibialis  posticus 
tendon,  which  pull  against  each  other  from  opposite  sides.  The  latter 
tendon  also  helps  to  maintain  the  longitudinal  arch.  When  the  trans- 
verse arch  is  properly  maintained  the  anterior  pillar  of  the  longitudinal 
arch  rests  upon  the  heads  of  the  first  and  fourth  metatarsal  bones  only; 
that  of  the  fifth  also  presses  upon  the  ground  in  many  cases,  especially 
when  more  weight  is  borne  on  the  foot.  If  the  transverse  arch  yields,  the 
heads  of  the  intervening  metatarsal  bones  receive  undue  pressure  and 
callosities  develop  over  them.  The  longitudinal  arch  is  maintained 
principally  by  the  inferior  ligaments  of  the  mediotarsal  joint,  the  long 
and  short  plantar  and  the  inferior  calcaneoscaphoid  ligaments.  The 
former  are  the  main  support  of  the  outer,  firmer,  and  less  elastic  part  of 
the  arch;  the  latter  is  known  as  the  "spring  ligament,"  as  it  is  the  principal 
ligament  that  supports  the  inner  and  more  springy  part  of  the  arch. 
It  helps  to  support  the  head  of  the  astragalus,  part  of  which  rests  directly 
upon  it.  It  in  turn  is  supported  by  the  tibialis  posticus  tendon,  which  runs 
in  a  groove  on  its  under  surface  and  comes  into  action  when  the  heel  is 
raised  and  the  weight  is  thrown  onto  the  instep,  and  therefore  when  the 
most  strain  comes  on  this  ligament  in  supporting  the  head  of  the  astrag- 
alus and  the  mediotarsal  joint.  The  short  muscles  to  the  toes  arising 
from  the  calcaneum  also  help  to  maintain  this  arch.  The  tibialis  anticus 
is  said  to  support  the  keystone,  but  as  no  keystone  can  be  supported,  but 
only  weakened,  by  traction  from  above,  it  can  only  support  it  by  reason  of 
the  fact  that  the  constituents  of  the  arch  are  connected  and  supported 
by  ligaments. 

Club  Foot. — The  longitudinal  arch  sometimes  yields  and  flattens  out. 
This  gives  rise  to  one  variety  of  club  foot  known  as  "flat  foot,"  in  which 
the  foot  is  pronated  (everted),  the  fore  foot  is  abducted,  the  sole  becomes 
flat,  and  the  patient  walks  mainly  on  the  inner  side  of  the  foot.  Some 
abduction  of  the  fool  is  necessarily  associated  anatomically  with  raising 
of  tin-  outer  border,  or  pronation,  for  the  pronating  peronei  are  also 
abductors.  In  flat  foot  the  impression  of  the  wet  sole  on  a  sheet  of 
paper  ihowa  no  deep  concavity  along  the  inner  border,  as  normally, 
but  rather  a  convexity  (see  Fig.  190).  It  occurs  particularly  in  those 
who  stand  a  great  deal  and  especially  in  adolescents  whose  ankles  may 
be  originally  defective,  who  are  below  pur,  who  have  grown  rapidly,  and 
in  idiom  die  muscles,  ligaments,  and  tascue  are  weakened,  relaxed,  and 


546 


THE  LOWER  EXTREMITY 


more  ready  to  yield  to  long-continued  pressure.  The  inferior  calcaneo* 
scaphoid  ligament  suffers  most,  and,  when  the  tibialis  posticus  fails 
support,  it  yields  and  allows  the  weight  of  the  body  to  press  the  head 
of  the  astragalus  downward,  forward,  and  inward,  so  that  the  latter, 
together  with  the  depressed  sustentaculum  tali  and  the  scaphoid  tuber- 
osity, form  prominences  on  the  inner  border  of  the  foot,  which  may  rest 
on  the  ground.  They  may  even  form  the  main  points  of  support  along 
the  inner  border.  The  plantar  and  deltoid  ligaments  and  the  plantar 
fascia  also  yield,  and  in  time  the  deformity  may  be  rendered  permanent 
by  alterations  in  the  shape  of  the  bones,  by  contraction  of  the  ligaments 
that  are  relaxed,  and  by  shortening  of  the  peronei  muscles,  which  are 
relaxed  by  the  abduction  and  eversion  of  the  foot.  In  the  acquired 
deformity,  occurring  in  the  developed  foot  of  adolescents  or  adults,  the 
affected  tarsal  bones  and  articulations  suffer  abnormal  pressure  or 
stretching,  which  often  causes  severe  pain.  The  latter  gives  rise  to  the 
term  "painful  flat  foot,"  to  distinguish  it  from  a  similar  deformity  without 


Fig.  190 


Flat  foot. 


Normal  foot. 


pain,  which  may  be  congenital.  The  acquired  deformity  is  also  known 
as  acquired  talipes  valgus,  the  congenital  as  congenital  talipes  valgus. 
The  latter  is  usually  associated  with  some  talipes  calcaneus. 

The  normal  foot  is  not  flat  at  birth.  Some  depression  of  the  astragalus 
and  prominence  of  the  internal  malleolus  may  be  seen  in  a  normal  foot 
when  the  entire  weight  of  the  body  is  borne  on  it.  Flat  foot  is  not 
uncommon  in  connection  with  genu  valgum,  for  the  weight  descends  to 
the  inner  side  of  the  heel  and  hence  is  transmitted  to  the  astragalus 
somewhat  from  without  inward.  It  may  also  result  from  a  Pott's 
fracture  in  which  the  eversion  is  not  sufficiently  corrected. 

Talipes. — Talipes  is  a  term  applied  to  all  forms  of  club  foot,  of  which 
there  are  four  primary  varieties  which  may  be  variously  combined  with 
one  another.  In  talipes  equinus  the  heel  is  drawn  up  by  the  contraction 
of  the  calf  muscles  so  that  the  patient  walks  on  the  balls  of  the  toes.  The 
arch  of  the  foot  is  often  exaggerated,  and  the  mediotarsal  joint  is  in  marked 
plantar  flexion.  Talipes  equinus  is  rarely  congenital,  and  results  from 
infantile  paralysis  of  the  extensor  tendons  and  other  paralytic  lesions, 


THE  FOOT  547 

as  well  as  from  the  long-continued  extended  position  of  the  foot,  due  to 
faulty  splints  or  the  weight  of  the  bedclothes  in  cases  of  long  illness,  etc. 
The  opposite  condition,  talipes  calcaneus,  is  characterized  by  dorsal 
flexion,  and  is  due  to  contraction  of  the  anterior  muscles,  usually  asso- 
ciated with  infantile  paralysis  of  the  posterior  groups.  The  patient 
walks  on  the  heel  with  the  foot  drawn  up.  It  is  rarely  congenital  and 
often  combined  with  talipes  valgus  and  pes  cavus. 

In  talipes  varus  the  foot  is  inverted  and  hence  also  adducted,  for  the 
same  muscles  produce  both  actions.  It  rarely  occurs  without  some 
talipes  equinus,  and  talipes  equinovarus  or  congenital  club  foot  is  the 
commonest  form  of  club  foot.  It  usually  originates  in  an  arrest  of  the 
fetal  development  of  the  feet,  resulting  in  the  delayed  rotation  of  the 
feet  and  legs,  so  that  the  equinovarus  position  of  the  feet  that  is  normal 
in  early  fetal  life  persists.  A  similar  deformity  may  result  from  infantile 
paralysis  of  the  extensor  and  peronei  muscles,  which  resist  plantar 
flexion  and  adduction  of  the  foot.  In  the  congenital  form  the  opposing 
calf  muscles,  flexors  and  adductors,  become  contracted,  resisting  the 
correction  of  the  deformity  and  gradually  increasing  it.  The  deformity 
is  a  kind  of  dislocation  inward  of  the  fore  part  of  the  foot  at  the  medio- 
tarsal  joint,  and  consists  of  elevation  of  the  heel,  inversion  and  adduction 
of  the  foot,  and  exaggeration  of  its  longitudinal  arch,  associated  with 
contracture  of  the  plantar  fascia.  Hence  the  patient  walks  on  the  outside 
or,  in  extreme  cases,  even  on  the  dorsum  of  the  foot.  The  toes  point 
inward,  so  that  one  foot  is  lifted  over  the  other  in  walking.  The  os  calcis 
becomes  more  vertical  than  horizontal;  the  astragalus  is  tipped  downward 
in  front,  so  that  the  fore  part  of  its  articular  surface  projects  under  the 
skin  and  only  its  posterior  part  articulates  with  the  tibia,  and  its  elon- 
gated Deck  is  bent  inward  and  downward;  the  atrophied  scaphoid,  with 
the  three  cuneiform  bones,  are  displaced  inward  and  backward,  near 
the  inner  malleolus;  and  the  cuboid,  displaced  upward  and  inward,  may 
become  the  chief  point  on  which  the  foot  rests  and  the  weight  is  borne. 
The  tarsal  bones  become  much  misshapen.  The  neck  of  the  astragalus 
is  deflected  inward  from  the  axis  of  its  body,  on  an  average,  at  an  angle 
of  ]'2.'.Y2  flegrees  in  the  adult,  35.76  degrees  at  birth  (Scudder),  and  50 
degrees  in  talipes  equinovarus.  The  ligaments  are  contracted  on  the 
concave  inner  side  and  stretched  on  the  other  side.  The  peroneus 
longns  tendon  may  slip  in  front  of  the  external  malleolus.  In  many 
of  club  foot  the  contracted  muscles  require  tenotomy,  also  the 
plantar  fascia  when  thai  is  contracted. 

The  chief  joints  of  the  foot  are  the  calcaneo-astragaloid,  the  medio- 
tarsal,  and  the  tarsometatarsal. 

The  i>rinri pal  ligament  of  the  calcaneo-astragaloid  joints,  from  a 
surgical    standpoint,   i-   the   massive  interosseous  ligament  in   the  sinus 
pedis.     The  lateral   ligaments  of  the  ;inkle,  the  surrounding  tendons 
the     virions    calcaneo-astragaloid    ;ind    the    external     calcaneoscaphoid 
ligaments  help  to  hold  the  bones  together.      This  is  a  double  joint,  the 

posterior  having  ;i  separate  synovial  sac,  the  anterior  a  sac  in  common 
with   the  astragak)  caphoid  joint.     The  movements  of  ab-  and  adduc- 


548  THE  LOWER  EXTREMITY 

tion  and  some  pro-  and  supination  are  allowed.  This  joint  is  of  prac- 
tical interest  in  subastragaloid  amputation,  subastragaloid  dislocation, 
dislocation  of  the  astragalus,  and  resection  of  the  astragalus. 

Subastragaloid  Dislocation. — Subastragaloid  dislocation  involves 
the  astragaloscaphoid  and  calcaneo-astragaloid  joints.  The  position 
and  relation  of  the  astragalus  with  the  tibia  and  fibula  and  the  move- 
ments in  the  ankle  joint  remain  normal.  In  these  dislocations  the  foot  is 
displaced  either  (1)  inward,  or  rather  inward  and  backward,  or  (2)  out- 
ward, very  rarely  (3)  backward  or  (4)  forward.  The  reason  of  this  is  to 
be  found  in  the  direction  of  the  opposed  surfaces  of  the  calcaneum  and 
scaphoid,  which  slant  from  above  and  behind  downward  and  forward. 
Hence  dislocation  forward  of  the  foot  is  very  rare  (2  cases  reported). 
The  rounded  head  of  the  astragalus  offers  little  resistance  to  lateral  or 
backward  and  inward  movement  of  the  scaphoid  and  displacement  of 
the  foot,  but  it  may  help  to  account  for  the  rare  occurrence  of  com- 
plete backward  dislocations.  The  two  forms  (1)  and  (2)  are  about 
equally  common.  Were  it  not  for  the  resistance  offered  by  the  project- 
ing sustentaculum  tali  and  the  outward  obliquity  of  the  posterior 
articular  process  of  the  calcaneum,  outward  displacement  of  the  foot 
would  be  the  more  common,  for  the  weight  of  the  body  is  transmitted 
to  the  astragalus  in  such  an  inward  direction  as  would  tend  to  displace 
it  inward  and  the  foot  outward. 

In  the  dislocation  inward  and  backward  the  dorsum  is  shortened,  the 
heel  lengthened,  the  foot  adducted  and  supinated,  the  external  malleolus 
and  the  head  of  the  astragalus  are  very  prominent  on  the  outer  side  of  the 
dorsum,  and  the  internal  malleolus  is  deeply  buried.  The  deformity 
resembles  talipes  varus.  The  cause  is  often  forcible  inversion  and  adduc- 
tion of  the  foot,  usually  from  a  fall  from  a  height.  In  the  outward  dis- 
location either  the  outward  displacement  may  be  combined  with  marked 
abduction  of  the  toes,  when  the  foot  turns  on  the  posterior  calcaneo- 
scaphoid  joint,  if  the  bones  have  not  separated  there,  or  the  foot  may  be 
displaced  bodily  outward.  Hence  the  dislocation  may  be  incomplete  as 
regards  the  posterior  calcaneo-astragaloid  joint.  When  the  foot  is 
abducted  there  is  more  or  less  eversion  and  the  head  of  the  astragalus 
is  very  prominent  on  the  inner  side.  In  the  form  with  simple  outward 
displacement  the  inner  malleolus  is  very  prominent  and  approaches  the 
level  of  the  sole.  The  head  of  the  astragalus  projects  below  and  in  front 
of  it,  while  the  outer  malleolus  is  buried  in  the  depression  above  the 
prominence  of  the  outer  surface  of  the  calcaneum  and  cuboid.  The 
interosseous  calcaneo-astragaloid,  the  astragaloscaphoid,  and  one  of 
the  lateral  ligaments  of  the  ankle  are  commonly  torn.  Subastragaloid 
dislocations  are  often  compounded. 

Dislocation  of  the  Astragalus. — Dislocation  of  the  astragalus  is 
a  combination  of  the  subastragaloid  dislocation  and  that  of  the  ankle, 
and  is  much  more  frequent  than  either  of  them.  It  is  often  compound, 
and  either  or  both  malleoli  may  be  fractured.  The  astragalus  may  be 
displaced  anteroposteriorly  or  laterally.  Dislocation  outward  and  for- 
ward is  the  commonest  form,  inward  and  forward  the  next,  directly 


THE  FOOT  549 

forward  or  backward  are  rare,  and  inward  is  almost  unknown.  In 
the  dislocation  outward  and  forward  the  head  of  the  astragalus  rests  on  the 
cuboid  and  external  cuneiform,  and  is  freely  movable.  The  foot  is 
adducted,  inverted,  and  usually  displaced  inward,  so  that  the  internal 
malleolus  is  buried,  the  external  is  prominent.  In  the  inward  and  for- 
ward dislocation  the  head  of  the  astragalus  projects  below  and  in  front  of 
the  inner  malleolus,  and  is  much  depressed,  as  if  rotated  on  a  transverse 
axis.  The  foot  is  usually  everted  and  abducted,  but  sometimes  simply 
displaced  outward. 

The  malleoli  are  brought  nearer  the  sole  in  almost  all  cases  of  dis- 
location of  the  astragalus.  In  addition  to  the  above  forms  of  displace- 
ment, the  astragalus,  while  remaining  within  the  tibiofibular  mortise, 
may  rotate  on  its  anteroposterior  axis,  sometimes  on  its  vertical  axis. 
If  reduction  under  anesthesia  or  by  open  operation  fails,  excision  of 
the  astragalus  should  be  done.  Dislocation  of  one  or  more  of  the  other 
tarsal  and  of  the  metatarsal  bones  occasionally  occurs,  the  most  frequent 
being  dislocations  of  the  scaphoid,  the  inner  cuneiform,  or  the  first  meta- 
tarsal.    The  latter  is  usually  displaced  upward. 

The  Mediotarsal  Joint. — The  mediotarsal  joint,  composed  of  the  astra- 
galoscaphoid  and  calcaneocuboid  joints,  is  the  most  movable  of  the  tarsal 
joints  and  permits  ab-  and  adduction,  pro-  and  supination,  and  flexion 
and  extension  of  the  fore  part  of  the  foot  on  the  back  part.  Flexion 
in  these  joints  is  simultaneous  with  extension  of  the  ankle,  and  vice  versa. 
In  these  movements  flexion  is  combined  with  adduction  and  supination 
of  the  foot,  extension  with  abduction  and  pronation  of  the  foot,  owing 
to  the  obliquity  of  the  axis  of  this  joint,  from  within  outward  and  some- 
what backward  and  downward.  This  combination  is  seen  in  talipes 
varus  and  valgus,  in  which,  as  well  as  in  pes  cavus  and  pes  planus,  the 
principal  displacement  occurs  in  the  mediotarsal  joint.  In  studying 
the  arches  of  the  foot  we  have  seen  that  the  inferior  ligaments  of  this  joint 
(the  inferior  calcaneoscaphoid  and  the  plantar  ligaments)  are  the  princi- 
pal support  of  the  longitudinal  arch.  Injury  at  the  mediotarsal  joint 
is  usually  avoided  by  the  elasticity  of  the  anterior  pillar  of  the  arch  of  the 
foot. 

Exclusive  of  thai  of  the  ankle,  there  are  six  synovial  membranes 

among  the  joints  of  the  tarsus  and  sometimes  seven,  if  there  is  a  separate 

between  the  enboid  and   external  cuneiform.      The  most  extensive 

is  that    between   the  scaphoid   and  the  three  cuneiform   bones,   which 

tends  forward  between  the  latter  to  the  second  and  third  tarsometa- 
tarsal joints  and  the  joints  between  the  second  and  third  and  third  and 
fourth  metatarsal  bone..      Hence  disease  of  the  bones  in  relation  to  this 
Would    be    mosl    likely  to  extend,   while  that    of    the  bones  near  the 

posterior  calcaneo-astragaloid  joint  would  be  least  likely  to  do  so. 

Through  each  of  the  three  principal  joints  of  the  fool  thai  we  have 
named,  amputation  may  be  practised.  In  subastragaloid  amputation  the 
astragalu  i  di  articulated  from  the  calcaneum  and  the  scaphoid  and  two 
synovial  sacs  ate  opened.  The  extremity  rests  on  the  astragalus  and  the 
operation  gives  ;i  good  result    The  stump  is  longer,  broader,  and  more 


550  THE  LOWER  EXTREMITY 

thickly  padded  than  that  after  Symes'  amputation.  The  end  of  the  stump 
is  liable  to  be  pulled  up  and  back  by  the  tendo  Achillis  taking  on  a  firm 
attachment  (Farabeuf ).  In  Chopart's  amputation  through  the  mediotarsal 
joint  two  synovial  sacs  are  opened.  Subsequently,  from  contraction  of 
some  muscles  or  loss  of  the  point  of  attachment  of  their  antagonists,  the 
heel  may  be  drawn  up  by  the  calf  muscles  so  that  the  scar  on  the  anterior 
face  is  turned  downward,  or  the  inner  border  of  the  stump  may  be 
raised  so  that  it  rests  on  the  outer  border.  It  is  not  well  suited  to  cases 
of  bone  disease,  and  the  operation  is  now  seldom  practised.  The  land- 
marks have  been  given  for  Lisfranc's  amputation  through  the  tarsometa- 
tarsal joint  and  the  only  difficulty  pointed  out,  i.  e.,  the  backward  projec- 
tion of  the  second  metatarsal  bone  between  the  outer  and  inner  cuneiform 
bones,  where  its  chief  bond  of  union  with  the  tarsus  is  the  interosseous 
ligament  that  connects  it  with  the  inner  cuneiform.  Hey's  operation 
avoids  the  difficulty  of  disarticulat  ng  this  bone  by  sawing  through  it, 
in  the  line  of  the  other  joints.  Neither  operation  is  often  indicated  or 
even  possible  in  conditions  depending  on  accident  or  disease. 

Far  better  than  Chopart's  amputation  are  the  two  following  ampu- 
tations of  the  foot.  In  Symes'  amputation  the  incision  runs  from  the 
tip  of  the  outer  malleolus  vertically  downward,  then  transversely 
across  the  sole  and  vertically  up  on  the  inner  side  to  12  mm.  (^  in.) 
below  the  inner  malleolus.  This  brings  the  end  of  the  inner  incision  at 
the  same  height  as  the  external.  The  soft  parts  covering  the  heel  are 
dissected  carefully  away  from  the  calcaneum,  and  the  tough  skin  of  the 
heel,  accustomed  to  bearing  pressure,  covers  the  stump  left  by  sawing 
the  leg  bones  just  above  the  articular  cartilages.  The  skin  of  the  inner 
part  of  the  heel  flap  is  supplied  by  the  internal  calcaneal  branch  of  the 
posterior  tibial  artery  and  the  calcaneal  branches  of  the  external  plantar 
artery,  and  it  is  most  important  for  the  life  of  the  flap  not  to  cut  off  this 
blood  supply,  as  may  be  done  by  carrying  the  internal  limb  of  the 
incision  farther  back  than  directed. 

Pirogoff 's  amputation  closely  resembles  Symes'  except  that  the  incision 
is  carried  a  little  farther  forward;  the  calcaneum  is  sawed  through  in  the 
line  of  incision,  or  more  obliquely  (from  above  downward  and  forward) ; 
the  sawed  surface  of  the  posterior  segment  of  the  calcaneum  is  applied  to 
the  under  sawed  surface  of  the  tibia;  the  astragalus  is  removed  with  the 
foot;  and  the  tendo  Achillis  is  not  divided.  Owing  to  the  position  of  the 
incision,  the  plantar  vessels  are  divided  farther  forward  than  in  Symes' 
operation,  so  that  there  is  less  danger  of  gangrene  of  the  skin  on  the  inner 
side  of  the  heel.  In  amputation  of  the  great  toe  the  large  size  of  the  head 
of  the  first  metatarsal  bone  must  be  borne  in  mind,  so  as  to  cut  the 
flaps  large  enough  to  cover  it  and  bring  the  line  of  the  cicatrix  above 
the  plantar  surface,  for,  as  it  is  one  of  the  anterior  ends  of  the  longi- 
tudinal arch,  this  surface  is  subject  to  much  pressure. 

Morton's  metatarsalgia  has  been  thought  (Morton)  to  be  due  to  the 
pinching  of  branches  of  the  external  plantar  nerve  between  the  head  and 
neck  of  the  fourth  metatarsal  bone  and  the  bony  prominences  of  the  fifth 
metatarsophalangeal  joint.     It  is  probably  often  due,  however,  to  the 


PLATE  LVIII 


FIG.  191 


FIG.    192 


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y. 


EXTERNAL    SAPHENOUS    I.    M.S. 

ANTERIOR    TIBIAL    IV     V.    L.    I.    S 

EXTERNAL    PLANTAR- 
INTERNAL    PLANTAR     IV     V.    L. 


Areas  of  Distribution  of 
Cutaneous  Nerves  of  the 
Front,  of  the  Lower  Limb. 
<W.   Keiller,  after  Testut.) 


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INTERNAL     | 
CALCANEAN 
I.    II.    S. 

Areas  of  Distribution  of 
Cutaneous  Nerves  of  the 
Back  of  the  Lower  Limb. 
(Testut.) 


THE  FOOT  551 

compression  of  a  communicating  branch  between  the  fourth  division  of  the 
internal  plantar  and  the  external  plantar  between  the  head  of  the  fourth 
metatarsal  and  the  ground  (R.  Jones).  The  fact  that  this  affection 
is  usually  associated  with  collapse  of  the  transverse  arch,  which  increases 
the  pressure  on  the  parts  beneath,  and  the  situation  of  the  digital  nerves, 
superficial  to  or  beneath  and  not  between  the  bones,  supports  this  view. 
It  is  a  painful  affection  occurring  at  the  base  of  the  fourth  (or  third  and 
fourth)  toe  of  adults,  most  often  in  women. 

The  calcaneum  is  more  often  fractured  than  any  of  the  tarsal  bones. 
By  a  fall  on  the  heel  it  may  be  splintered  and  crushed,  especially  in  its 
anterior  half,  and  its  vertical  diameter  may  be  decreased,  so  that  the 
sole  is  flattened  and  the  malleoli  are  approximated  to  it.  By  a  forcible 
contraction  of  the  calf  muscles  the  calcaneum  has  occasionally  been 
fractured,  always  behind  the  astragalus  and  sometimes  only  the  hind 
part,  which  attaches  the  tendo  Achillis.  The  latter  is  usually  ruptured 
in  place  of  fracture  of  the  calcaneum  from  muscular  violence.  The 
displacement  of  the  fragment  is  sometimes  slight,  sometimes  extreme, 
11  cm.  (4th  in.)  (Constance).  In  fractures  of  the  calcaneum  from  mus- 
cular action,  and  often  in  other  fractures  of  this  bone,  dorsal  flexion 
causes  local  pain  by  the  traction  of  the  taut  tendo  Achillis  on  the 
posterior  fragment.  The  astragalus  alone  may  be  fractured  by  falls,  but 
the  lesion  is  often  associated  with  fracture  of  the  calcaneum,  or  at  the 
ankle,  etc.  Fracture  of  the  other  tarsal  bones,  the  metatarsals,  and  the 
phalanges  is  commonly  due  to  direct  violence.  Such  fractures  are  often 
compound,  owing  to  the  scanty  covering  of  soft  parts  on  the  dorsum  of 
the  foot,  which  are  usually  contused  or  lacerated.  I  have  observed  one 
case  in  which  fracture  of  the  tubercle  at  the  base  of  the  fifth  metatarsal 
bone  occurred  on  both  sides,  at  an  interval  of  several  months,  by  avulsion 
of  the  peroneus  brevis  tendon  in  a  sudden  inversion  of  the  foot.  The 
fracture  was  shown  by  the  o:-rays. 

The  Toes. — The  toes  very  closely  resemble  the  fingers,  except  in 
size,  and  are  liable  to  similar  lesions  from  injury,  inflammation,  etc., 
though  not  so  frequently.  Dislocation  of  the  proximal  phalanx  of  the 
great  toe  is  similar  to  that  of  the  like  joint  of  the  thumb  in  the  character 
of  the  lesion,  the  difficulty  of  reduction,  and  the  reasons  for  this  diffi- 
culty. A  peculiar  affection  of  the  toes  known  as  "hammer  toe,"  in 
which  the  proximal  phalanx  is  extended  while  the  middle  is  strongly 
flexed,  is  most  often  found  in  the  second  toe,  which  is  normally  longer 
than  the  others.  It  is  due  to  a  contraction  of  the  extensor  tendon  and 
of  the  glenoid  and  lateral  ligaments  of  the  first  phalangeal  joint. 

The  cutaneous  nerve  supply  of  the  lower  extremity  is  shown  by 
Figs.  I'M  and  I!'-'. 

Paralysis  of  the  Lower  Extremity. — Paralyses  of  the  lower  ex- 
tremity  are  common  and  usually  due  (o  a  lesion  of  the  cord,  hence  they 
involve  nil  or  .i  considerable  group  of  nerves.  Occasionally  a  single 
nerve  trunk  is  paralyzed  by  a  ford  lesion  or  a  lesion  of  the  nerve  below 
n  <••'(  from  the  spinal  canal.  This  involves  ;i  limited  area  of  anes- 
thesia  or  motor  paralysis.  An  example  of  motor  paralysis  of  ;i  group 
or  groups  of  muscles  i    ieeo  not  infrequently  after  infantile  paralysis. 


552  THE  LOWER  EXTREMITY 

Paralysis  of  the  anterior ,  crural  nerve  may  be  due  to  fractures  and 
tumors  of  the  pelvis  or  spine,  psoas  abscess,  dislocations  of  the  hip,  stab 
wounds  in  the  groin,  and  perhaps  a  partial  lesion  of  the  cauda  equina. 
If  the  entire  nerve  is  paralyzed  the  patient  cannot  flex  the  hip,  as  in 
rising  from  the  recumbent  position  (iliopsoas  and  pectineus),  or  extend 
the  knee  (quadriceps),  and  the  knee  jerk  is  lost.  The  sartorius  is 
paralyzed,  the  pectineus  partly  so,  being  supplied  in  part  by  the 
obturator.  In  the  parts  supplied  by  the  internal  and  middle  cutaneous 
and  the  long  saphenous  nerves  anesthesia  exists. 

The  obturator  nerve  alone  is  seldom  paralyzed,  but  may  be,  occasionally, 
from  the  pressure  of  the  fetal  head  or  an  obturator  hernia  or  from  lesions 
similar  to  those  paralyzing  the  anterior  crural.  The  patient  cannot 
adduct  the  thighs  or  cross  the  legs  (adductors),  and  outward  rotation  of 
the  thigh  is  impaired  (obturator  externus  and  adductors).  Sensation 
of  the  cutaneous  area  supplied  (mesial  aspect  of  thigh)  is  impaired. 

Paralysis  of  the  external  popliteal  alone  is  not  uncommon,  that  of  the 
internal  popliteal  is  rare.  It  is  usually  due  to  infantile  paralysis,  to 
traumatism  below  the  bifurcation  of  the  great  sciatic,  and  sometimes 
to  pressure  within  the  pelvis  on  the  sacral  plexus.  In  the  latter  case 
the  external  popliteal  (peroneal)  nerve  is  the  one  usually  paralyzed,  for 
its  fibers  arise  mostly  from  the  lumbosacral  cord  which  is  exposed 
to  pressure  where  it  crosses  the  pelvic  brim.  The  anterior  tibial 
branch  or  the  entire  peroneal  nerve  are  the  nerves  that  most  often 
remain  paretic  after  infantile  paralysis.  The  peroneal  nerve  may 
also  be  injured  in  tenotomy  of  the  biceps  tendon,  and  still  more  often 
where  it  winds  around  the  fibula,  below  its  head,  by  pressure  between 
the  bone  and  the  operating  table,  a  splint,  etc.,  by  contusion  at  the 
same  point,  by  fractures  of  the  fibula  or  by  a  sudden  strain.  In 
paralysis  of  the  internal  popliteal  nerve  the  patient  cannot  extend  the 
ankle,  flex  or  stand  upon  the  toes  (muscles  of  the  back  of  the  leg),  or 
move  the  toes  laterally  (short  muscles  of  the  sole).  Adduction  and 
supination  of  the  foot  is  impaired  (tibialis  posticus).  The  sensation 
in  the  skin  of  the  sole,  the  plantar  surface  and  ends  of  the  toes,  the  outer 
border  of  the  foot,  and  the  back  of  the  leg  is  impaired.  In  para7ysis  of  the 
external  popliteal  nerve  the  patient  is  unable  to  flex  the  ankle,  abduct  or 
pronate  the  foot,  or  fully  extend  the  toes  (anterior  leg  muscles  and  peronei). 
Hence  the  toes  drag  in  walking  ("drop  foot"),  so  that  the  knee  must  be 
unduly  flexed  to  prevent  it.  Adduction  and  supination  are  impaired 
(tibialis  anticus).  Only  the  ends  of  the  toes  can  be  extended  by  the 
interossei.  The  arch  of  the  foot  may  be  somewhat  flattened  by  the 
paralysis  of  the  peroneus  longus.  In  some  cases  the  anterior  tibial 
muscle  escapes  paralysis.  The  anterior  tibial  nerve  has  been  injured 
in  fractures  of  the  tibia.  Sensation  over  the  outer  side  and  the  adjacent 
part  of  the  front  and  back  of  the  leg  and  the  dorsum  of  the  foot  is 
impaired. 

In  paralysis  of  the  great  sciatic  flexion  of  the  knee  is  lost  (hamstrings), 
and  external  rotation  of  the  thigh  is  impaired  (obturator  internus  and 
quadratus  femoris)  in  addition  to  the  results  of  paralysis  of  both  the 


THE  FOOT  553 

internal  and  external  popliteal  nerves.  Paralysis  of  the  great  sciatic 
may  be  due  to  pelvic  tumors.  These  more  commonly  cause  a  neuralgia 
of  the  nerve.  Paresis  or  neuralgia  of  the  individual  nerves  of  the 
lower  extremity  may  be  produced  by  similar  causes.  Hence  it  must 
be  borne  in  mind  that  pain  in  any  part  of  the  lower  extremity  may 
be  due  to  lesions  at  a  distance,  intraspinal,  intra-abdominal,  intra- 
pelvic,  etc. 

In  the  diagnosis  of  the  situation  of  lesions  of  the  cord,  due  to  disease 
or  fracture,  a  knowledge  of  the  skin  areas  and  the  muscles  of  the  lower 
extremity  supplied  by  the  several  segments  of  the  cord  is  important. 
For  this  see  the  chapter  on  the  Spine. 


CHAPTER    VII. 

THE   SPINE. 

Landmarks  and  Topography. — By  deep  pressure  a  little  below  the 
occiput  the  spine  of  the  axis  may  be  felt.  The  spines  of  the  next 
three  vertebrae  can  only  be  felt  with  much  d  fficulty  on  account  of  their 
shortness,  the  presence  of  the  ligamentum  nuchse,  and  the  forward  curve 
of  the  cervical  vertebrae.  That  of  the  sixth  cervical  may  be  nearly  as 
long  as  the  seventh  (Fig.  193)  and  is  easily  felt.  When  exposed  by 
incision  it  may  be  distinguished  by  being  the  last  bifid  spine,  as  a  rule. 
On  account  of  the  prominence  of  the  spine  of  the  seventh  cervical  the 
latter  is  called  the  vertebra  prominens,  but  the  spine  of  the  first  dorsal  is 
the  most  prominent.  However,  we  usually  begin  to  count  the  spines  from 
the  seventh  cervical.  But  unless  all  can  be  felt  from  the  second  down,  it 
is  safer  to  confirm  the  count  by  counting  up  from  the  fourth  lumbar, 
unless  the  sixth  cervical  is  to  be  exposed  by  incision.  The  third  thoracic 
spine  is  on  a  level  with  the  inner  end  of  the  spine  of  the  scapula;  the 
seventh  with  the  lower  end  of  the  scapula;  the  fourth  lumbar  spine  with 
the  highest  part  of  the  iliac  crest  and  the  bifurcation  of  the  abdominal 
aorta;  the  second  sacral  spine  with  the  posterior  superior  iliac  spine  and 
the  centre  of  the  sacro-iliac  joint;  the  third  sacral  spine  with  the  upper 
border  of  the  great  sciatic  notch;  and  the  first  piece  of  the  coccyx  with  the 
spine  of  the  ischium.  The  twelfth  rib  leads  to  the  twelfth  thoracic  verte- 
bra. The  umbilicus  is  on  a  level  with  the  interval  between  the  third  and 
fourth  lumbar  spines.  The  thoracic  spines  are  oblique  and  overlap 
one  another,  in  the  middle  of  the  series  being  opposite  the  disk  below 
the  next  lower  body.  The  broad  lumbar  spines  are  more  horizontal 
and  are  opposite  the  disk  (and  the  upper  part  of  the  body)  below  it. 
The  transverse  process  of  the  atlas  is  palpable  a  little  below  and  in  front 
of  the  tip  of  the  mastoid  process,  moving  with  the  head  in  rotation. 
The  anterior  tubercle  of  the  sixth  cervical  vertebra  (carotid  tubercle)  is 
felt  on  a  level  with  the  cricoid  cartilage.  The  bodies  of  the  upper  three 
cervical  vertebra  only  can  be  satisfactorily  felt  through  the  mouth  at  the 
back  of  the  pharynx,  the  anterior  arch  of  the  atlas  being  on  a  level  with 
the  hard  palate. 

The  spinal  column  is  required  to  serve  many  different  functions:  (1)  to 
bear  the  weight  of  the  head  and  upper  extremities;  (2)  to  give  attach- 
ment to  the  ribs;  (3)  to  serve  as  the  central  axis  of  the  body,  to  con- 
nect its  upper  and  lower  segments;  (4)  to  diminish  the  effect  of  shocks 
and  jars;  (5)  to  allow  of  varied  and  extensive  movements,  and  yet  (6) 
to  provide  a  solid  canal  which  safely  contains  the  spinal  cord. 

Corresponding  to  the  increasing  weight  to  be  borne  by  the  vertebral 


THE  SPINE 


555 


bodies,  as  we  pass  from  the  upper  end  of  the  spine  to  the  sacrum,  we 
find  that  their  surface  area  gradually  increases  from  above  downward. 
To  allow  the  varied  and  extensive  movements  without  injury  to  the 
delicate  cord  within,  the  spine  is  composed  of  a  number  of  small  articu- 
lated segments,  the  movement  between  any  two  of  which  is  not  great, 
while  that  of  the  spine  as  a  whole  is  quite  considerable.    More  free  move- 

Fig.  193 


CERVICAL 
VERTEBR/E 


THORACIC 
VERTEBR/E 


LUMBAR 
VERTEBR/E 


The  tpinal  column,  right  lateral  view  and  dorsal  new.     (Gerri  a,  aftei  Ti 

men(  between  b  smaller  number  of  segments  would  not  only  weaken  the 
spine  and  make  it  more  liable  to  injur} ,  bui  also  expose  the  cord  (<»  com- 
ion  by  being  sharply  bent,  as  if  is  in  diastasis  of  Mir  spine. 

Of  the  four  anteroposterior  curves  only  I  wo,  the  thoracic  and  sacral, 

an  present  at  birth,    Hiese  are  primary  curves,  due  to  the  shape  of  die 

and  are  convex  backward  to  give  more  room  in  the  thoracic  and 


556  THE  SPINE 

pelvic  cavities,  which  they  help  to  form.  The  cervical  and  lumbar 
curves,  convex  forward,  are  principally  due  to  the  shape  of  the  interver- 
tebral disks.  They  become  developed  from  the  weight  of  the  body 
and  the  traction  of  the  muscles  when  the  erect  position  is  assumed,  and 
are  more  or  less  fixed  about  the  sixth  or  seventh  year.  They  are  com- 
pensatory curves  to  allow  the  child  to  sit  or  stand  erect.  Otherwise 
the  head  would  project  forward  and  a  marked  dorsal  convexity  would 
exist  in  the  thoracic  region.  This  position  is  seen  in  the  aged,  in 
whom  it  largely  depends  upon  the  shrinkage  of  the  disks,  whereby  the 
compensatory  curves  dependent  upon  them  are  flattened,  and  thus  the 
primary  permanent  thoracic  curve  is  exaggerated. 

The  normal  curves  of  the  spine  may  be  exaggerated  so  as  to  constitute 
the  several  forms  of  curvature  of  the  spine. 

Increase  of  the  posterior  convexity  in  the  thoracic  region  is  known  as 
kyphosis.  This  is  almost  always  due  to  a  tuberculous  caries  of  the  bodies 
of  the  thoracic  vertebrae,  and  is  known  as  "  Pott's  disease  of  the  spine." 
When  the  softened  spongy  tissue  of  the  affected  vertebral  bodies  yields 
to  the  pressure  of  the  superincumbent  weight  the  spine  bends  forward 
above  the  seat  of  the  disease,  thereby  throwing  backward  the  spinous 
processes  opposite  the  diseased  area.  This  gives  rise  to  an  angular  cur- 
vature or  hump  back,  which  is  accompanied  by  an  increase  of  the  cer- 
vical and  lumbar  compensatory  curves.  Hence  to  avoid  deformity 
and  allow  healing  in  spinal  caries,  the  superincumbent  weight  should  be 
relieved  by  apparatus  (plaster  jacket)  or  posture.  When  the  disease 
attacks  the  cervical  or  lumbar  vertebra?  there  is  no  marked  angular 
curvature,  but  the  normal  posterior  concavity  of  these  regions  is  flattened 
out  and  the  affected  part  of  the  spine  is  rendered  stiff.  The  neural 
arches  and  the  circumference  of  the  vertebral  canal  almost  always 
escape  the  tuberculous  process. 

The  spinal  caries  is  often  associated  with  abscess  which  tends  to  sink 
in  the  line  of  gravity  along  the  spine.  Spinal  abscesses  in  the  thoracic 
or  lumbar  region  tend  to  enter  the  sheath  of  the  psoas  muscle,  in  the 
former  region  after  passing  beneath  the  internal  arcuate  ligament.  They 
are  the  common  cause  of  psoas  abscess.  If  the  curvature  is  extreme,  or 
comes  on  rapidly,  the  front  of  the  cord  may  be  pressed  upon  by  the  pio- 
jection  at  the  back  of  the  vertebral  bodies  and  motor  paralysis  results. 
More  often  the  cord  symptoms  are  due  to  the  pressure  of  inflammatory 
thickening,  deposit  or  abscess  within  the  canal,  which  also  first  press  on 
the  anterior  or  motor  portion  of  the  cord,  for  they  are  derived  from  the 
lesion  in  the  bodies,  anteriorly.  They  may  subside  from  general  treat- 
ment, but  if  degenerative  changes  in  the  cord  appear  the  spinal  canal 
should  be  opened  to  remove  the  cause  of  pressure.  In  recent  years 
angular  curvatures  of  the  spine  have  been  successfully  treated  by  forcible 
straightening.  This  must  create  a  gap  anteriorly  between  the  bodies 
equal  to  the  amount  of  the  loss  or  compression  of  the  bone.  It  is  not 
without  risk.  In  severe  cases  the  chest  becomes  much  distorted  and 
the  lower  ribs,  resting  on  or  below  the  iliac  crests  or  sinking  into  the 
pelvis,  obliterate  the  iliocostal  space. 


THE  SPINE 


557 


Lordosis  is  an  increase  of  the  forward  curve,  as  in  the  lumbar  and 
cervical  regions.  It  is  most  marked  and  most  often  observed  in  the  lum- 
bar  region.  It  is  almost  invariably  a  compensatory  curve  instinctively 
assumed  to  keep  the  centre  of  gravity  from  being  advanced  too  far  and 
to  allow  the  patient  to  stand  erect.  Thus  in  obesity,  pregnancy,  angular 
curvature,  congenital  dislocation  of  the  hips,  and  in  hip  disease  with 


Fig.  194 


Fig.  195 


Diagrams  to  ihow  tordona  ;is  a  compensa- 
ting corw  in  hip  diaeaee:  A,  normal  spinal 
'I  It*-  liip  Ea  ankyioeed  In  the  flexed 
>n ;  H,  the  ankyloaed  Bexed  hip  is  si  raight- 
i-iK-1  by  ■  tilting  of  the  pehrie,  indicated  by 
the  poaition  of  the  'lot t <-< l  Una  and  the  prea- 
■ 


Diagram  to  show  lateral  curvature  of  the 
spine.  The  primary  curve  is  to  the  right  in 
the    thoracic  region,  the  compensatory   curves 

in   the  opposite  direction  in  tin rvioal  and 

lumbal    regions.      The     vertebral     spines    are 
.shown   rotated    toward   the  convexity  of  the 

QUI  \  '•. 


flexion  of  the  femur,  it  is  present  as  a  compensatory  curve.  The  latter 
condition  la  Us  commonest  cause.  The  liij)  being  held  or  ankylosed  in 
a  flexed  position,  the  patient  is  only  enabled  to  straighten  it  by  a  rota- 
tion of  the  entire  pelvis,  by  which  its  upper  end  is  moved  for  ward,  which 

increases  the  lltmbar  curve.      This  is  seen  in  examining  fUCh  I  patient  in 

the  supine  position.    When  the  affected  extremity  is  extended  the  lum- 


558  THE  SPINE 

bar  spine  is  arched  forward;  when  it  is  flexed  to  the  angle  in  which  it  is 
ankylosed  the  lumbar  curve  is  normal;  and  when  it  is  further  flexed  the 
curve  is  straightened  and  the  lumbar  spines  press  the  hand  against  the 
table. 

Scoliosis  or  Lateral  Curvature. — Scoliosis  or  lateral  curvature  may 
also  be  said  to  be  an  exaggeration  of  a  normal  curve,  for  very  few  are 
without  a  slight  lateral  spinal  curve,  usually  to  the  right  in  right-handed 
persons.  Scoliosis  also  may  be  a  compensatory  curve,  compensating  the 
lateral  tilting  of  the  pelvis  which  accompanies  hip  disease  (p.  402)  or  an 
inequality  of  the  length  of  the  legs.  It  may  be  due  to  chronic  empyema, 
or  the  extensive  resection  of  several  ribs  to  cure  it.  More  often  it  is  an 
idiopathic  condition  whose  etiology  we  do  not  fully  understand  in  many 
cases.  It  occurs  in  children,  most  often  in  girls,  in  whom  the  muscular 
development  and  general  condition  are  below  par.  A  faulty  attitude  in 
sitting  at  study  or  in  standing  is  the  most  common  cause.  As  the  prin- 
cipal curve,  in  the  upper  thoracic  region,  is  usually  convex  to  the  right  in 
right-handed  persons,  unequal  muscular  action  is  thought  to  be  a  caus- 
ative factor.  There  are,  of  course,  compensatory  curves  in  the  opposite 
direction  in  the  lumbar  and  often  in  the  cervical  regions  to  allow  the 
erect  attitude.  In  addition  the  vertebrae  of  the  curved  portion  are  rotated 
or  twisted  on  a  vertical  axis,  so  that  the  bodies  always  turn  to  the  convex 
side  of  the  curve.  These  changes  are  due  to  the  yielding  of  the  bone  to 
static  causes  and  abnormally  distributed  pressure.  They  occur  in  the 
normal  spine  when  it  is  bent  laterally.  When  the  faulty  position  is  long 
maintained  the  vertebrae  become  wedge-shaped  at  the  apex  of  the  curve, 
lozenge-shaped  above  and  below,  and  much  distorted,  as  if  the  part 
behind  the  centrum  were  bent  toward  the  concave  side.  This  brings 
the  spines  nearer  the  median  line,  so  as  to  diminish  the  appearance  of 
the  curve  as  indicated  by  them.  It  also  carries  the  ribs  backward  on  the 
right  and  forward  on  the  left,  so  that  the  right  chest  is  prominent  pos- 
teriorly but  flattened  anteriorly,  while  the  left  chest  is  prominent  in 
front  but  its  ribs  are  more  oblique  and  crowded  together.  The  right 
lung  is  compressed  and  most  of  the  work  must  be  done  by  the  other. 
Tuberculous  affections  of  the  apex  of  the  lung  are  present  in  a  large 
majority  of  such  patients,  usually  on  the  side  of  the  convexity  of  the 
curve.  The  scapula  on  the  convex  side  is  prominent  posteriorly  and 
elevated.  The  iliocostal  space  is  diminished,  but  the  ilium  is  more 
prominent  on  the  concave  side.  In  time  the  vertebrae,  muscles,  and 
ligaments  become  atrophied  and  contracted  on  the  concave  side, 
stretched  on  the  convex  side. 

The  spinal  canal  is  completed  posteriorly  by  the  fusion  of  the  laminae, 
or  neural  arches,  at  the  root  of  the  spinous  processes.  Each  half  of 
the  neural  arch  is  formed  from  a  separate  ossific  centre.  Failure  of 
this  fusion  causes  a  posterior  median  defect  of  the  laminae  and  spines 
which  is  seen  in  spina  bifida.  This  is  most  common  in  the  lumbosacral 
region,  for  here  the  neural  arches  are  last  ossified  and  fused  together. 
Other  imperfections  of  development  are  often  associated  with  spina 
bifida. 


THE  SPINE  559 

Spina  Bifida. — Spina  bifida  is  a  congenital  defect  of  the  vertebral 
canal  through  which  some  of  its  contents  protrude,  i.  e.,  (1)  the  meninges 
alone  may  protrude  as  a  sac  containing  cerebrospinal  fluid  (spinal 
meningocele)',  (2)  the  sac  may  also  contain  a  portion  of  the  flattened 
cord  or,  generally,  on  account  of  its  position  the  nerve  trunks  of  the 
cauda  equina,  which  usually  adhere  to  the  posterior  wall  of  the  sac 
meningomyelocele)',  (3)  the  sac  may  consist  of  the  dilated  cord,  enclosed 
by  its  membranes,  containing  a  sac-like  dilatation  of  its  central  canal 
(syringomyelocele).  The  second  variety  is  the  most  common,  the  first, 
the  next,  and  the  third  the  rarest.  In  all  forms  the  sac  is  filled  with 
cerebrospinal  fluid,  in  the  first  two  forms  from  the  subarachnoid  space. 
Hence  the  sac,  which  forms  a  median  dorsal  tumor,  is  more  tense  in 
the  upright  position  and  on  crying.  Pressure  may  return  some  of  the 
fluid  and,  by  increasing  the  pressure  within  the  spinal  canal,  may  result 
in  causing  irregular  muscular  movements  or  even  convulsions.  Menin- 
goceles give  no  symptoms  but  the  presence  of  the  tumor,  as  a  rule.  In 
the  other  two  forms,  however,  paralysis  of  the  rectum  and  the  bladder 
with  more  or  less  paralysis  and  sensory  disturbances  are  usually  present. 
These  involve  the  lower  extremity  owing  to  the  common  site  of  the 
defect  in  the  lumbosacral  region.  These  symptoms  usually  depend 
upon  a  defect  of  the  cord  or  nerve  roots,  but  they  may  be  due  in  part  to 
pressure.  In  spina  bifida  occulta  there  is  a  defect  of  the  neural  arch, 
but  no  hernia-like  protrusion.  There  may  be  other  tumors,  such  as 
lipomata,  in,  over,  or  beneath  the  bony  cleft.  The  skin  over  the  cleft 
presents  a  hairy  patch.  In  rachischisis  there  is  an  entire  absence  of 
union  of  the  walls  of  the  medullary  canal,  including  the  bone  and  the 
cord,  which  forms  the  walls  of  the  central  canal. 

The  twenty-three  intervertebral  disks  make  up  nearly  one-fourth  of  the 
length  of  the  spine,  hence  the  height  of  the  body  is  appreciably  de- 
creased  from  their  compression  on  long  standing  or  sitting,  and  in  old 
age  from  the  shrinkage  of  the  disks.  It  is  owing  to  the  disks  that  the 
movements  of  the  spine  are  permitted,  and  these  movements  are  most 
free  where  the  vertebrae  are  smallest  or  the  intervening  disks  thickest, 
i.  e.,  in  the  cervical  and  lumbar  regions  respectively.  Therefore  move- 
nt* nt  is  most  fnc  where  the  spinal  canal  and  cord  are  the  largest,  where 
the  curve  is  convex  forward,  and  where  there  are  no  bony  cavities 
containing  viscera.  Free  movement  in  the  thoracic  region  would 
be  a  distinct  menace  to  the  thoracic  viscera.  The  degree  of  mobility 
depends  upon  flic  thickness  of  flic  disks,  the  size  and  shape  of  the  bodies, 
and  the  direction  of  the  articular  and  spinous  processes.  Movement  is 
most  free  in  the  lumbar  region,  next  in  the  cervical  region  where  rota- 
tion and  lateral  motion  are  the  freest,  and  least  free  in  the  thoracic  region. 
The  movements  of  the  spine  arc  less  free  than  often  supposed.  Flexion 
it  most  free  in  the  lumbar  region,  extension  in  the  lumbar  and  last 
thoracic  vertebra;,  which  functionally  are  like  the  lumbar  vertebrae. 
Lateral  bending  is  always  accompanied  by  a  rotation  of  the  bodies  of 
the  vertebrae  to  the  convexity  of  the  lateral  curve  in  the  thoracic  region 

and  to  if    concavity  in  the  cervical  arid  lumbar  regions.     This  movement 


560  THE  SPINE 

is  greatest  in  the  cervical  and  upper  thoracic  regions  in  flexion  of  the 
spine,  and  at  the  dorsolumbar  junction  in  extension  of  the  spine  (Lovett). 

The  vertebral  bodies  with  the  intervening  pulpy  portion  of  the  disks 
really  form  ball-and-socket  joints,  but  the  free  movements  thereby 
allowed  are  resisted  by  the  connecting  ligaments  and  restricted  by  the 
articular  processes  and  in  parts  by  the  other  processes  of  the  vertebrae. 
Owing  to  the  more  or  less  horizontal  surfaces  of  the  articular  processes 
of  the  cervical  region,  movements  in  all  directions  are  permitted  there. 
Rotary  movements  are  most  free  in  the  atlo-axoid  joints,  flexion  and 
extension  in  the  occipito-atloid  joints.  In  the  thoracic  region  extension 
is  prevented  by  the  overlapping  spines  and  by  the  shape  of  the  artic- 
ular processes.  The  latter  limit  flexion  also,  whereas  lateral  move- 
ments, otherwise  possible,  are  limited  by  contact  between  the  ribs.  In 
the  lumbar  region  lateral  movements  are  limited  by  the  great  transverse 
diameter  of  the  bodies,  rotation  by  the  relation  of  the  articular  processes. 

The  overlapping  lamina  protect  the  cord  from  injury  in  the  thoracic 
region,  where,  owing  to  the  curve,  it  lies  nearer  the  surface  and  is  most 
exposed.  Between  the  upper  cervical  vertebra  the  intervals  between  the 
narrow  laminae  are  widest,  and  here  the  cord  can  be  most  easily  reached 
and  wounded  by  a  narrow  instrument.  Infanticide  has  been  accom- 
plished by  pithing  the  upper  cervical  cord  by  a  long  narrow  pin,  thrust 
between  the  upper  cervical  vertebrae  or  between  the  atlas  and  the  occiput. 
Again,  in  the  lumbar  region  it  is  possible  to  enter  the  spinal  canal  by  an 
instrument  thrust  obliquely  upward  and  forward.  This  is  taken  advan- 
tage of  in  lumbar  puncture  and  spinal  anesthesia.  The  puncture  is 
made  between  any  two  lumbar  spines  below  the  second  lumbar  vertebra 
(usually  between  the  third  and  fourth),  to  avoid  the  cord  which  extends 
to  the  lower  end  of  the  first  lumbar.  To  avoid  the  spines  the  puncture 
is  made  a  little  (^  to  1  cm.)  to  one  side  of  the  median  line.  In  adults  the 
puncture  is  made  just  outside  of  the  upper  margin  of  the  spinous  process 
below  the  interval,  to  give  the  needle  the  desired  upward  obliquity.  The 
needle  is  then  thrust  forward,  toward  the  middle  line,  and  in  adults 
slightly  upward,  for  2  to  7.5  cm.,  until  the  escape  of  fluid  (cerebro- 
spinal) indicates  that  its  point  has  entered  the  subarachnoid  space. 
This  occurs  at  a  depth  of  2  to  3  cm.  (f  to  1^  in.)  in  children  and  4  to 
7.5  cm.  (If  to  3  in.)  in  adults.  The  canal  is  entered  through  the  liga- 
mentum  subflavum,  which  is  felt  to  offer  slight  resistance  to  the  passage 
of  the  point.  The  puncture  of  one  of  the  nerves  of  the  cauda  equina 
may  possibly  occur  and  is  shown  by  the  twitching  of  some  of  the  mus- 
cles of  the  lower  extremity. 

On  account  of  the  number  of  the  joints  and  ligaments  of  the  spine 
and  the  variety  and  extent  of  its  movements  it  is  readily  understood 
why  the  spine  is  liable  to  sprains.  That  these  sprains  are  not  more 
common  is  due  to  the  very  number  of  the  joints  which  tend  to  diffuse  the 
force  applied  to  the  spine.  These  naturally  occur  most  often  where  the 
movements  are  most  free,  in  the  lumbar  and  cervical  regions,  and  where 
fixed  and  movable  parts  of  the  spine  join  one  another,  at  the  dorso- 
lumbar and  the  cervico-occipital  junctions.     The  nearness  of  the  head 


THE  SPINE  561 

and  the  transmission  of  violence,  received  by  it,  to  the  spine  may  increase 
the  tendency  to  sprains  in  the  cervical  region,  especially  where  it  joins 
the  head.  Considerable  pain  and  stiffness  often  persist  long  after  the 
injury,  and  these  may  depend  upon  a  synovitis  of  one  or  more  of  the 
many  vertebral  joints.  Ecchymosis  rarely  appears  in  these  cases,  for 
the  spine  is  separated  from  the  skin  by  many  layers  of  muscles  and 
fasciae. 

When  the  violence  applied  is  more  concentrated  or  more  severe,  frac- 
tures or  dislocations  of  the  spine  are  produced.  The  liability  of  the 
spine  to  these  accidents  is,  to  be  sure,  diminished  by  its  elasticity,  due  to 
its  curves,  its  disks,  etc.,  and  by  the  number  of  its  segments.  Some  have 
even  denied  the  possibility  of  dislocation  of  the  spine  without  fracture, 
except  perhaps  in  the  cervical  region,  where  the  small  size  of  the  bodies 
and  the  less  firm  interlocking  of  the  more  horizontally  directed  articular 
processes  do  not  offer  so  much  resistance  to  the  separation  of  the  vertebras. 
But  in  many  cases  the  associated  fracture  is  unessential  to  the  production 
of  the  dislocation. 

Dislocation. — Dislocation  is  most  common  in  the  cervical  region,  espe- 
cially between  the  fifth  and  sixth  vertebrae.  Thoracic  and  lumbar  dis- 
locations are  very  rare,  and  mostly  involve  the  twelfth  thoracic  vertebra. 
The  dislocation  is  almost  always  of  the  upper  vertebra  forward,  and 
may  be  complete  or  incomplete,  bilateral  (dislocation  by  flexion),  or 
unilateral  (dislocation  by  abduction  and  rotation).  In  the  latter  form 
the  articular  facet  of  one  side  is  dislocated  forward  in  front  of  the  corre- 
sponding facet  of  the  vertebra  below,  and  the  axis  of  its  displacement 
passes  through  the  articular  facets  of  the  other  side.  In  this  form  there 
are  no,  or  very  slight,  symptoms  of  injury  of  the  cord,  for  the  lumen  of 
the  canal  is  but  little  invaded.  Bilateral  dislocations  are  commonly  due 
to  overbending  of  the  spine,  especially  hyperflexion. 

Most  dislocations  of  the  spine  are  partly  dislocation  and  partly 
fracture,  and  as  it  is  usually  impossible  to  distinguish  between  the  two 
lesions,  furthermore  as  the  effects  of  the  two  are  similar,  it  is  best  to 
consider  them  together.  The  term  fracture  dislocation  is  often  applied 
to  all  such  injuries  of  the  spine.  About  20  per  cent,  of  spinal  injuries 
are  [jure  dislocations,  20  per  cent,  pure  fractures,  and  the  rest  fracture 
dislocations. 

Fracture  of  the  Spine. — Fractures  of  the  spine  may  be  due  to  indirect 

or  direct  violence.    Those  due  to  the  latter  are  rare  and  usually  confined 

to  the  spines  and  lamina  in  the  thoracic  or  cervical  region.    The  injury 

to  the  cord  i-  less  severe  and  Less  common,  as  a  rule,  in  this  class  of 

,  for  much  displacement  is  rare. 

Fractures  from  Indirect  Violence.-  Fractures  from  indirect  violence  are 
■  illij  (I in-  in  ;i  forcible  bending  of  the  spine  in  a  fall  or  by  the  weight 
of  ;i  falling  body.  The  breaking  of  die  neck  by  diving  in  shallow  water 
i  ;ui  example.  The  relative  frequency  of  the  injury  in  t he  lower  cervical 
spine  and  ui  the  thoraoicolufnbaf  junction  may  be  partly  explained  by  the 
free  mobility  ;ii  these  points,  by  the  fad  thai  ;it  these  points  ;i  flexible  and 
a  rigid  portion  of  the  spine  meet,  and,  in  the  cervical  region,  by  the  small 
36 


562  THE  SPINE  . 

size  of  the  bodies.  The  eleventh  and  twelfth  thoracic  and  the  first  lum- 
bar vertebrae  are  fractured  more  often  than  any  other  three  vertebrae  and 
more  than  half  the  fractures  of  the  spine  occur  below  the  tenth  thoracic 
vertebra.  Both  regions  where  fractures  are  of  common  occurrence  are  far 
enough  from  the  ends  of  the  spine  to  be  affected  by  powerful  leverage 
from  both  sides.  The  sternum  and  ribs  may  act  to  some  extent  as 
a  splint  to  protect  the  thoracic  part  of  the  spine.  As  most  spinal  frac- 
tures are  due  to  forced  flexion,  the  anterior  portions  of  the  bodies  of  one 
or  more  vertebrae  are  pressed  together  and  more  or  less  crushed  and 
flattened,  compression  fractures,  while  the  neural  arches  are  pulled  apart. 
It  is  noticeable  that  the  large  cancellous  bodies  are  well  adapted  to  resist 
compression,  while  the  neural  arches  and  their  connecting  ligaments  are 
well  suited  to  resist  traction.  These  compression  fractures  occur  most 
frequently  at  the  dorsolumbar  junction.  If  the  violence  continues, 
flexion  of  the  spine  may  go  on  until  the  articular  processes  are  so 
separated  as  to  allow  dislocation,  and  a  fracture  dislocation  occurs. 
The  kyphosis  due  to  the  isolated  fracture  is  increased.  In  other  cases 
with  hyperflexion  a  tearing  fracture  occurs  in  an  oblique  direction  from 
above  and  behind  downward  and  forward,  sometimes  through  two  verte- 
brae. These  fractures  are  usually  fracture  dislocations,  though  one  or  both 
of  the  articular  processes  may  be  fractured  instead  of  dislocated.  They 
present  the  greatest  amount  of  displacement  and  occur  most  commonly  at 
the  cervicodorsal  junction.  In  compression  fractures  and  in  all  fracture 
dislocations  there  is  more  or  less  kyphosis  opposite  the  site  of  fracture. 
Fractures  or  dislocations  of  the  atlas  and  axis  are  particularly  serious, 
owing  to  their  relation  to  the  medulla  and  their  situation  above  the 
phrenic  nerve  roots.  These  injuries  are  immediately  fatal  if  the  cord 
is  crushed.  The  various  processes  may  also  be  fractured  in  a  case,  of 
fracture  dislocation.  The  following  is  the  order  of  relative  frequency  for 
the  various  regions  and  processes:  The  spines  in  the  thoracic,  cervical, 
and  lumbar  regions;  the  transverse  processes  in  the  cervical,  lumbar, 
and  thoracic  regions;  the  articular  processes  in  the  cervical,  thoracic,  and 
lumbar  regions.  Fracture  of  the  articular  processes  increases  the  liability 
of  displacement  by  removing  one  of  the  posterior  processes  which  tend 
to  lock  the  vertebrae  together. 

The  displaced  parts  may  often  be  returned  to  the  normal  position,  par- 
ticularly in  the  cervical  and  thoracic  regions.  This  may  occur  spon- 
taneously, so  that  on  examination  no  irregularity  of  contour  is  discovered, 
or  it  may  be  done  by  the  surgeon.  The  line  of  fracture  is  usually  nearer 
the  upper  than  the  lower  surface  of  the  bodies,  and  there  is  more  or  less 
laceration  of  the  contiguous  disk  in  all  cases,  as  well  as  of  the  ligaments 
connecting  the  spines,  laminae,  and  articular  processes.  The  injury  to 
the  bones  is  the  least  important  part  of  fracture  dislocations  of  the  spine; 
that  of  the  contained  cord  is  the  most  so.  The  latter  from  its  size,  which 
is  smaller  than  that  of  the  canal,  and  from  its  method  of  suspension  in 
the  vertebral  canal  (see  p.  564),  may  escape  injury,  and  is  injured  only 
when  the  lumen  is  considerably  encroached  upon  by  the  displacement 
of  the  fragments.    This  displacement  is  almost  always  of  the  upper  frag- 


THE  SPINAL  CORD  563 

ment  forward,  or  forward  and  downward,  on  the  lower,  and  is  most  con- 
stant and  most  marked  in  fracture  dislocations.  The  cord  is  thus  com- 
pressed against  the  sharp  posterior  edge  of  the  vertebral  body  below  the 
line  of  fracture  by  the  arch  of  the  vertebra  above.  Thus  the  anterior 
or  motor  portion  of  the  cord  suffers  first  and  foremost,  and,  if  the  crushing 
of  the  cord  is  not  complete,  sensation,  which  is  partly  conducted  in 
the  posterior  part,  may  be  retained  in  whole  or  in  part.  The  reflexes, 
centring  in  the  central  gray  matter,  may  also  be  preserved. 

Symptoms. — The  symptoms  are  largely  those  of  the  injury  to  the 
cord.  In  fractures  in  which  there  is  or  has  been  no  displacement  there 
may  be  almost  no  symptoms,  except  those  of  the  fracture,  resembling  a 
severe  sprain.  The  external  deformity  shows  only  a  displacement  of  the 
vertebrae  or  a  lesion  of  the  laminae  and  spinous  processes.  This  external 
deformity  consists  in  an  anteroposterior  or  lateral  deviation  of  the  spines 
at  the  point  of  injury. 

The  spinal  canal  is  opened  by  laminectomy  in  certain  cases  of  fracture 
dislocation  of  the  spine,  especially  when  the  symptoms  do  not  indicate 
a  complete  crushing  of  the  cord  or  when  the  lesion  is  below  the  level 
of  the  cord  in  the  region  of  the  cauda  equina,  as  well  as  in  some  cases 
of  pressure  paralysis  with  beginning  degeneration  in  Pott's  disease, 
and  in  cases  of  tumors  within  the  canal.  The  cord  is  then  relieved  of 
pressure  by  the  removal  of  its  cause.  In  this  operation  the  spines  and 
lamina?  are  removed,  the  latter  as  near  as  possible  to  the  articular  pro- 
cesses. The  spines  and  laminae  are  exposed  by  a  free  median  incision 
and  by  the  detachment  and  retraction  to  either  side  of  the  overlying 
muscles.  Plexuses  of  veins  on  the  outer  and  inner  surfaces  of  the  laminae 
;ni(]  along  the  spines  may  give  rise  to  considerable  venous  bleeding.  In 
some  fractures  or  dislocations  of  the  spine  the  displacement  may  be 
mosi  readily  and  safely  reduced  by  exposing  the  injured  part,  with  or 
without  removal  of  sonic  of  the  processes  or  laminae. 

The  Spinal  Cord. 

Topography.  The  lower  end  of  the  spinal  cord,  corresponding  to 
the  tip  of  die  conus  medullaris,  extends  to  the  end  of  the  spinal  canal 
in  early  fetal  life,  to  the  third  lumbar  vertebra  at  birth,  and  to  the  disk 
below  the  first  lumbar  vertebra  in  the  adult.  It  is  raised  1  cm.  when 
tli*-  body  is  bent  forward  and  the  arms  are  raised.  The  spinal  mem- 
branes, containing  cerebrospinal  fluid,  reach  to  the  level  of  the  second  or 

third   sacral   Vertebra,  SO  that  infected   injuries  here  may  produce  spinal 

meningitis.  The  cervical  enlargement  is  mainly  opposite  (lie  fourth,  fifth, 
sixth,  and  seventh  cervical  vertebra;, and  measures  13  nun.  transversely; 
the  lumbar  enlargement  is  largely  opposite  the  eleventh  and  twelfth 
thoracic  vertebrae,  and  measures  I-  mm.  transversely.  In  the  thoracic 
region  'he  cord  measures  I"  nun.  transversely  and  8  nun.  anteropos- 
terior^, h  I")  cm.  'I',  ft. j  in  length  and  I \  ounces  in  weight 
The  manner  in  which  the  cord  is  suspended  within  the  vertebral  canal, 
which  it  does  ool  nearly   fill,  accounts  in  part  for  its  frequent  escape 


564  THE  SPINE  . 

from  injury.  The  strong  spinal  dura  forms  a  tubular  sheath  (theca) 
for  the  cord  and  an  investment  for  each  nerve  as  it  passes  through  it. 
It  is  continuous  with  the  dura  of  the  cranium,  but,  unlike  it,  does  not 
serve  as  the  periosteum  of  the  bones  bounding  the  canal,  but  is  separated 
from  them  by  a  considerable  interval  containing  loose  areolar  and 
fatty  tissue  and  plexuses  of  veins.  The  latter  may  give  rise  to  extensive 
hemorrhage  in  injuries  to  the  spine,  and  the  extravasated  blood  tends 
to  gravitate  toward  the  lower  part  of  the  canal,  where  sufficient  quantity 
may  collect  to  cause  pressure  symptoms.  So  tough  and  loosely  connected 
with  the  bones  is  the  dura  that  it  is  usually  untorn  by  a  fracture,  even 
when  the  cord  is  completely  crushed.  In  fact  the  contained  cord  is  so 
delicate  that  it  may  be  thoroughly  disorganized  without  apparent  alter- 
ation of  its  form.  The  strength  and  thickness  of  the  dura  is  such  as  to 
offer  considerable  resistance  to  the  invasion  of  disease  from  without, 
even  to  malignant  tumors  or  tuberculosis.  Inflammation  of  the  dura, 
and  also  of  the  underlying  meninges,  after  injuries  of  the  spine,  is  much 
less  frequent  than  similar  complications  after  injuries  of  the  skull.  By 
the  communication  through  the  ligamenta  subflava  between  the  dorsal 
spinal  veins,  on  the  posterior  aspect  of  the  neural  arches,  and  the  venous 
plexuses  within  the  canal,  inflammation  may  travel  from  without  to  the 
spinal  meninges.  In  this  way  spinal  meningitis  has  followed  carbuncle 
at  the  back  of  the  neck  or  deep  bed-sores  over  the  sacrum. 

The  subdural  space,  or  the  space  between  the  dura  and  arachnoid,  in 
the  spinal  canal  is  merely  a  potential  one,  the  two  membranes  being 
normally  in  contact,  so  that  in  dividing  the  dura  we  divide  the  outer 
layer  of  arachnoid  and  enter  the  subarachnoid  space.  The  latter  space 
contains  a  large  amount  of  cerebrospinal  fluid  which  surrounds  the  cord. 
The  cord  is  suspended  in  this  fluid,  being  connected  with  the  layers  of 
the  meninges  just  mentioned  only  by  the  nerve  roots  and.  the  ligamentum 
denticulatum  on  either  side,  and  the  delicate  fibers  of  the  arachnoid 
reaching  from  the  dura  to  the  pia,  especially  that  dorsal  median  par- 
tition known  as  the  septum  posterius.  These  processes  serve  to  steady 
the  cord,  surrounded  by  fluid,  in  its  position  within  its  theca.  The 
cord  is  thus  admirably  protected  from  injury. 

This  fluid  is  continous  with  the  subarachnoid  fluid  about  the  brain 
and,  through  the  foramen  of  Magendie,  with  that  within  the  cerebral 
ventricles.  Thus  in  the  case  of  a  spina  bifida,  which  contains  this  same 
fluid,  fluctuation  may  sometimes  be  felt  at  the  anterior  fontanelle  on 
compressing  the  tumor,  and  when  the  fluid  is  drained  from  a  spina 
bifida  so  much  may  escape  that  the  brain  loses  the  support  of  its  water- 
bed,  and  convulsions  may  occur  from  its  irritation  against  the  uneven 
base  of  the  skull.  Convulsions  may  also  occur  in  lumbar  puncture  if 
the  pressure  is  too  much  reduced.  The  normal  pressure  of  this  fluid  in 
the  recumbent  position  is  said  to  support  a  column  of  water  5  cm.  (2  in.) 
high,  but  in  inflammation  and  some  other  diseased  conditions  it  may 
reach  a  height  many  times  greater.  Normally  the  fluid  is  absorbed 
when  its  pressure  is  greater  than  that  in  the  surrounding  veins,  and 
in  diseased  conditions  the  pressure  may  be  relieved  by  lumbar  puncture. 


PLATE  LIX 


FIG.   196 


ANT.   NERVE 
BOOTS 


Section  of  the  Cord  and  its  Membranes,  to  show  the  manner 
of  suspension  of  the  cord  within  the  vertebral  canal.  Dia- 
grammatic.    (Testut. 


THE  SPINAL  CORD  565 

7m  spinal  anesthesia  an  amount  of  fluid  is  withdrawn  equivalent  to  that 
of  the  solution  to  be  introduced,  so  as  not  to  alter  the  pressure.  The 
percentage  of  albumin  in  this  fluid  is  very  low,  0.05  per  cent.,  far  below 
that  of  blood  serum,  but  it  is  greatly  increased  in  inflammation,  and  this 
increase  is  a  diagnostic  sign.  Lumbar  puncture  is  also  useful  diagnos- 
tically  by  allowing  a  bacteriological  and  microscopic  examination  of  the 
fluid,  and,  as  this  fluid  comes  from  about  the  brain  as  well  as  the  cord, 
it  is  also  useful  in  some  cerebral  conditions.  Thus  tubercle  bacilli  are 
often  found  in  cases  of  tuberculous  meningitis,  and  the  diplococci  of 
cerebrospinal  meningitis  in  cases  of  the  latter.  The  presence  of  numer- 
ous cells  indicates  inflammation  and  that  of  blood  a  pachymeningitis 
or  an  injury.  Therapeutically  it  has  proved  of  less  value.  It  suggests 
itself  in  hydrocephalus,  but  is  nothing  more  than  palliative.  In  a  few 
cases  of  spinal  injury  it  appears  to  have  been  serviceable.  By  means 
of  the  free  communication  established  by  this  fluid  between  the  spinal 
and  cranial  cavities  it  affords  a  ready  means  of  the  spread  of  inflam- 
mation from  one  to  the  other.  Blood  extravasated  into  the  subarach- 
noid space,  in  case  of  injury,  may  readily  extend  from  end  to  end  of 
the  cord,  and  tends  to  gravitate  toward  its  lower  end,  but  extensive 
hemorrhage  in  this  space  is  not  common. 

In  spite  of  the  marvellous  provision  for  the  protection  of  the  cord,  a  train 
of  severe  and  complicated  symptoms  sometimes  follows  certain  injuries 
to  the  spine.  These  symptoms  are  attributed  by  some  to  concussion  of 
the  cord,  comparable  to  concussion  of  the  brain,  but  they  are  more 
complex  than  the  symptoms  of  the  latter.  Concussion  of  the  brain  is 
of  brief  duration,  but  the  long  duration  of  the  symptoms  in  question 
would  indicate  gross  changes  in  structure,  rather  than  the  vague  "molec- 
ular changes"  often  assumed  as  their  cause,  and  the  provisions  for  the 
protection  of  the  cord  would  not  admit  of  such  a  gross  lesion  from  the 
injury  received.  If  such  symptoms  depend  upon  a  distinct  lesion  of  the 
cord,  it  may  very  likely  be  a  hemorrhage  (hematomyelia),  the  diagnosis 
of  which,  says  Thorburn,  when  the  symptoms  may  be  attributed  to  a 
single  focus  of  injury,  "should  always  be  preferred  to  the  vague  and 
unsatisfactory  designation  'concussion  of  the  spinal  cord.'  "  Many  sup- 
posed cases  of  the  latter  will  probably  be  eliminated  by  accurate  study. 
Such  a  lesion  is  probably  due  to  a  partial  dislocation  with  recoil,  an 
acute  bend,  or  a  diastasis  I  separation)  of  the  spine.  The  great  majority, 
however,  of  these  eases  of  supposed  "concussion  of  the  cord,"  known 
as  "railway  spine,"  because  they  so  often  occur  in  railway  accidents, 
are  examples  of  "traumatic  neuroses. 

Compression,  Contusion,  or  Crushing  of  the  Cord.  Compression, 
contusion,  or  crushingof  die  cord  is  what  constitutes  the  gravity  of  fracture 
dislocation*  of  (he  spine.  Compression  may  also  be  due  to  tumors, 
inflammatory  deposits,  etc.  \  stated  above,  in  fracture  dislocations 
with  displacement  die  eord  i-;  compressed  or  crushed  by  being  pressed 
by  the  oeural  arch  above  die  line  (,i'  fracture  against  die  sharp  postero- 
niperior  edge  of  die  body  below  die  fracture  Line.  The  anterior  part 
of  die  cord  i     therefore  first  and,  when  die  entire  cord  is  not  crushed, 


566 


THE  SPINE 


most  affected  by  the  injury.  It  is  important,  therefore,  both  for  diag- 
nosis and  prognosis,  to  know  something  of  the  conduction  paths  of  the 
cord  (Fig.  197). 

Motor  Tracts. — The  direct  pyramidal  tract,  or  column  of  Turck,  in 
the  mesial  part  of  the  ventral  column,  conveys  motor  fibers  from  the 
cerebral  cortex  on  the  same  side,  which  have  not  crossed  in  the  pyramids. 
They  eventually  reach  the  opposite  ventral  horn  by  crossing  through 
the  anterior  white  commissure.  They  comprise  about  15  per  cent,  of  the 
pyramidal  fibers,  and  extend  to  about  the  middle  of  the  thoracic  part 
of  the  cord.     The  crossed  'pyramidal  tracts  lie  in  the  posteromesial  part  of 

Fig.  197 


Columns  of  the  cord. 


the  lateral  columns  and  convey  motor  fibers,  which  have  crossed  in  the 
pyramid,  from  the  opposite  side  of  the  cerebral  cortex  to  the  ventral  horn 
of  the  same  side.  Lesions  of  these  two  columns  cause  a  paralysis  of  the 
muscles  below.  The  muscles  are  not  atrophied  unless  the  anterior  cornu 
of  gray  matter  is  involved. 

Sensory  Tracts. — The  direct  cerebellar  tract  on  the  posterolateral 
aspect  of  the  lateral  column,  separating  the  crossed  pyramidal  tract 
from  the  periphery,  is  an  ascending  or  sensory  tract  of  the  second  order, 
whose  axones  pass  from  the  cells  of  Clarke's  columns  to  the  cerebellum. 
The  anterolateral  or  Gowers'  tract  is  another  ascending  sensory  tract 


THE  SPINAL  CORD  567 

of  the  second  order  whose  axones  pass  from  the  cells  of  the  dorsal  horn, 
partly  from  the  same  and  partly  from  the  opposite  side,  to  the  cerebellum 
and  the  lemniscus.  GoWs  tract  (fasciculus  gracilis)  includes  the  dorsal  or 
sensory  root  fibers  that  pass  uninterruptedly  in  the  posterior  column  to 
the  nucleus  gracilis  of  the  medulla.  These  fibers  first  enter  Burdach's 
tract  and  are  gradually  displaced  medially  into  Goll's  tract  by  the  entry 
of  new  root  fibers.  Some  of  them  pass  up  to  the  nucleus  cuneatus  of 
the  medulla  in  the  median  part  of  Burdach's  column.  The  lateral  part 
of  Burdach's  tract  receives  most  of  the  fibers  entering  by  the  dorsal 
root.  These  soon  divide  into  ascending  and  descending  limbs  which 
give  off  collaterals,  which,  with  the  descending  and  some  of  the  ascend- 
ing stem  fibers,  pass  into  the  gray  matter  to  end  about  the  cells  of  the 
dorsal  horn  and  Clarke's  columns.  The  rest  of  the  ascending  stem 
fibers  pass  up  to  the  medulla  in  Goll's  and  Burdach's  tracts. 

Some  (reflex)  collaterals  end  in  relation  with  the  cells  of  the  anterior 
horns,  mostly  of  the  same  side.  The  latter  complete  the  reflex  arcs 
between  the  afferent  sensory  and  the  efferent  motor  fibers.  Any  loss 
of  continuity  in  the  arc  causes  the  loss  of  the  reflex.  In  the  crossed 
pyramidal  tracts  are  the  fibers  which  inhibit  the  reflexes  and  thus  keep 
them  under  control  of  the  brain.  When  a  lesion  involves  these  fibers 
the  inhibitory  control  of  the  brain  is  lost,  the  reflexes  are  exaggerated, 
and  a  spastic  paralysis  results.  Subsequently  the  muscles  become 
contractu  red. 

The  sensory  tracts  and  centres  of  the  cord  are  seen  to  be  mostly 
behind,  the  motor  in  front.  The  posterior  roots  convey  all  forms  of 
sensation,  and  all  forms  will  be  affected  by  a  lesion  in  the  lateral  part 
(root  zone)  of  Burdach's  tract.  After  entering  the  cord  the  fibers  con- 
veying the  several  forms  of  sensation  separate  from  one  another  and 
pursue  different  courses.  Thus  a  lesion  of  the  long  sensory  tract 
(Goll's  tract)  causes  loss  of  muscle  sense,  or  ataxia,  with  or  without 
anesthesia.  A  lesion  of  the  central  gray  matter  causes  analgesia  and 
thermo-anesthesia,  but  no  anesthesia. 

The  trophic  centres  of  the  motor  roots  and  nerves  are  the  nerve  cells  of 
the  anterior  horn.  Destruction  of  these  or  division  of  the  nerve  roots,  or 
thai  continuation  in  the  motor  nerves,  causes  degeneration,  the  reaction 
of  degeneration,  and  finally  the  absence  of  all  electrical  reaction  in  the 
motor  nerve  fibers  distal  to  the  lesion  which  cuts  them  off  from  their 
trophic  ecntrcs.  The  paralysis  due  to  such  lesions  is  flaccid  and  the 
reflexes  are  lost,  for  the  reflex  are  is  broken.  Rapid  atrophy  of  the  para- 
lyzed muscles  occurs.  The  trophic  centres  of  the  posterior  or  sensory 
roof  are  the  cells  of  the  gangha  of  the  roots.  Section  of  the  sensory 
fibers  distal  to  the  ganglia  causes  degeneration,  etc.,  distal  to  the  point  of 
section,  i.  <■.,  in  the  fibers  cul  off  from  their  trophic  centres.   After  section 

of  the  posterior  root   between   the  COrd   and   the  ganglion  degeneration 

occurs  only  centrally,  from  the  point  of  section  into  the  cord.  Regen- 
eration does  net  readily  occur  after  such  a  lesion,  as  the  degenerated 

fiber-  in  the  cord  do  not  regenerate.  All  sensory  functions  of  the  root 
are   l<.  <  nt    off   from    the   eonl,  bnl   there  is  no  degeneration 

distal  to  the  lesion,  as  it  is  not  cut  off  from  its  trophic  centre. 


Fig.  198 

iV.  to  rectus  lateralis 

_'J_to  rectus  antic,  minor 
.Anastomosis  with  hypoglossal 

.  Anastomosis  with  pneumogastrio 
_N.  to  rectus  antic.major. 
_N.  to  mastoid  region. 
_6reat  auricular  n. 
-Transverse  cervical  n. 
N.  to  Trapezius,  Ang.  Scap.  and  Rhomboid. 

Supra  clavicular  n. 
Supra-acromial  n. 
Phrenic  n. 

N.  to  levator  ang.  scap. 

iV.  to  rhomboid 

—Subscapular  n. 
-Subclavicular  n. 


N.  to  peetoralis  major. 


Circumflex  n. 

Musculo-cutaneous  n. 

Median  n. 

Radial  n. 

Ulnar  n. 

Internal  cutaneous  n. 

Small  internal  cutaneous  n. 


Jlio-hypogastric  n. 
Jlio-inguinal  n. 


-External  cutaneous  n. 
-Genito-crural  n. 


Anterior  crural  n. 
Obturator  n. 


. Superior  gluteal  n. 


N.  to  pyriformis 
N.  to  gemellus  super. 


N.  to  levator  ani 

iV.  to  obturator  int._ 

N.  to  ophincter  ani 

Coccygeal  n.. 

K N.  to  gemellus  infer. 

N.  to  guadratus 

Small  sciatic  n. 

Sciatic  n. 

The  relation  of  the  segments  of  the  spinal  cord  and  their  nerve  roots  to  the  bodies  and  spines 
of  the  vertebrae.      (D^jerine  et  Thomas,  Mai.  d.  1.  Moelle  Epiniere,  Paris,  1902.) 


THE  SPINAL  CORD  569 

The  distinction  between  partial  and  total  transverse  lesions  is  im- 
portant. In  partial  transverse  lesions  the  level  of  the  anesthesia  may 
not  correspond  to  that  of  the  paralysis.  The  anesthesia  may  be 
incomplete  or  irregular  in  distribution.  Paresthesia  is  often  marked, 
and  sharp  root  pains  occur  from  pressure  on  the  roots  within  the  canal. 
The  paralysis  may  be  less  rapid  in  onset,  irregular  in  distribution,  and 
variable  in  degree.  The  extensors  often  show  more  paralysis  than  the 
flexors.  One  side  may  be  affected  more  than  the  other,  and  improve- 
ment may  set  in  early.  The  deep  reflexes  are  exaggerated  or  soon 
become  so.  The  control  of  the  bladder  and  rectum  may  not  be  lost,  or, 
if  lost  at  first,  is  early  recovered  from. 

In  lesions  of  a  fart  of  the  cord  only,  as  from  compression  of  tumors, 
etc.,  the  white  tracts,  being  superficial,  are  first  affected  and  lose  their 
conductivity.  The  reflexes  become  exaggerated,  for  the  reflex  arc  is  intact 
and  the  cerebral  inhibition  is  cut  off  (see  above,  p.  567).  For  the  same 
reason  the  paralysis  is  spastic.  In  unilateral  lesions  the  paralysis  occurs 
on  the  same  side  as  the  lesion,  but  may  be  incomplete  or  early  recovered 
from,  owing  partly  to  the  incompleteness  of  the  lesion  on  that  side,  partly 
to  the  fibers  in  the  uninjured  half  of  the  cord,  in  the  direct  pyramidal 
tract,  which  cross  below  to  the  side  of  the  lesion.  This  double  inner- 
vation is  limited,  according  to  Wernicke  and  Mann,  to  the  extensors 
of  the  thigh  and  knee,  and  the  plantar  flexors  of  the  foot.  In  unilateral 
lesions  the  anesthesia  occurs  on  the  side  opposite  the  lesion,  except  the 
muscle  sense,  which  is  on  the  same  side.  There  is  often  hyperesthesia 
on  the  side  of  the  lesion.  From  these  clinical  facts  the  conclusion  is 
reached  that  sensory  impulses  pass  across  the  cord  and  ascend  in  the 
columns  of  the  opposite  side. 

In  complete  transverse  lesions  there  is  complete  motor  and  sensory 
paralysis  of  all  parts  supplied  by  nerves  arising  below  the  level  of  the 
lesion.  The  paralysis  is  flaccid  and  the  tendon  reflexes  are  lost,  though 
theoretically  we  would  expect  the  reverse,  for  the  reflex  arc  is  intact. 
There  is  no  trophic  atrophy  and  no  reaction  of  degeneration,  for  the 
trophic  centres  are  intact.  The  vasomotor  centres  are  paralyzed  and, 
partly  on  this  account,  there  is  a  tendency  to  decubitus  and  priapism. 
Control  of  the  bladder  and  rectum  is  lost.  There  are,  however,  no 
symptoms  which,  except  by  their  persistence,  prove  the  presence  of  a 
complete  transverse  lesion. 

In  partial  transverse  lesions,  when  the  paralysis  and  anesthesia 
do  not  correspond,  and  the  deep  reflexes  are  exaggerated  or  normal, 
or  when  the  anesthesia  is  incomplete  or  irregular  in  distribution, 
operation  (laminectomy)  offers  some  hope  and  is  justifiable.  Many 
condemn  operation  in  complete  transverse  lesions  on  the  ground  thai 
the  hopeless,  bu(    if    is   not   invariably  so,  owing  to  the  uncer- 

tainty of  tli'-  diagnosi  ,  and  in  many  such  eases  great  improvement  or 
nearly  complete  cure  lias  resulted.  The  recuperative  point  of  tit e  cord 
onsiderable  if  its  fibers  are  not  severed,  so  dial  after  severe  crushing 
ill*-  function  may  be  recovered  to  a  greater  or  less  extent.  Recent  ex- 
perience in  the  surgery  of  the  cord  is,  on  the  whole,  encouraging,  but 


570  THE  SPINE 

functional  union  of  the  divided  cord  has  not  been  proved  to  occur,  for 
regeneration  does  not  occur  in  the  fibers  of  the  cord,  a  fact  apparently 
associated  with  the  absence  of  the  neurilemma  sheath.  The  cauda  equina 
and  the  nerve  roots  are  'practically  'peripheral  nerves,  and  hence  resist 
trauma  well,  so  that  operation  should  be  the  rule  in  injuries  of  the  cauda 
equina,  especially  if  after  six  to  ten  weeks  the  bladder  and  rectum  symp- 
toms persist. 

The  determination  of  the  level  of  the  lesion  is  important  not  only 
in  traumatic  lesions,  but  even  more  so  in  those  due  to  a  tumor  or  an 
inflammatory  deposit.  For  this  purpose  there  are  three  means  at  our 
disposal:  the  extent  (1)  of  the  sensory  paralysis  and  pain,  and  (2)  of 
the  motor  paralysis,  and  (3)  the  condition  of  the  reflexes.  From  these 
we  can  judge  what  nerve  roots  and  therefore  what  spinal  segments 
are  involved.  The  cord  is  divided  into  as  many  segments  as  there  are 
spinal  nerves.  Each  segment  includes  the  roots  of  a  pair  of  spinal  nerves, 
the  dividing  line  between  two  adjoining  segments  passing  transversely 
between  the  superficial  origins  of  the  pairs  of  nerve  roots.  It  is  to  be 
noted  that  the  distribution  of  the  segments  or  nerve  roots  does  not 
correspond  to  that  of  the  peripheral  nerves,  but  to  parts  of  several.  Thus, 
in  the  trunk  the  sensory  areas  are  almost  horizontal.  The  cutaneous 
sensory  areas  are  shown  in  Fig.  199  and  in  column  E,  the  motor  distri- 
bution in  column  D,  Fig.  200.  Remember  that  the  cervical  nerves  appear 
above  their  respective  vertebrae,  the  thoracic  and  lumbar  nerves  below. 
The  level  of  the  anesthesia  (and  of  the  pain)  is  the  most  reliable  indica- 
tion for  the  niveau-diagnosis.  The  symptoms  due  to  a  lesion  of  a  segment 
or  of  its  nerve  roots,  at  a  lower  level,  are  the  same.  The  fact  that  formerly 
tumors,  etc.,  localized  by  the  level  of  the  anesthesia  were  often  found  at 
a  higher  level  is  explained  by  the  investigations  of  Sherrington,  who 
showed  that  a  single  segment  or  root  does  not  wholly  supply  a  given 
area  of  skin  (or  a  single  muscle),  but  at  least  three  (and  Bruns  says 
five)  adjoining  segments  participate.  Hence  the  cutaneous  area  of  each 
spinal  segment  so  overlaps  those  of  the  neighboring  segments  and  the 
posterior  primary  divisions  of  the  spinal  nerves  anastomose  so  freely 
with  each  other  that  a  lesion  of  a  single  segment  or  posterior  root  does 
not  cause  anesthesia,  for  the  area  supplied  by  it  is  also  supplied  by  the 
neighboring  segments.  It  requires  the  division  of  three  adjoining  pos- 
terior roots  to  produce  complete  anesthesia.  There  may  be  hypes- 
thesia  or  diminished  or  uncertain  sensation  in  the  area  supplied.  Hence 
the  upper  border  of  anesthesia,  due  to  the  pressure  of  a  tumor,  etc., 
points  to  a  lesion  of  the  next  higher,  or  perhaps  the  second  higher,  seg- 
ment than  that  represented  by  the  level  of  the  anesthesia,  for  the  area 
principally  supplied  by  the  upper  one  of  the  affected  segments  is  also 
supplied  by  the  segment,  or,  perhaps,  two  segments  above  it.  It  has  been 
shown  that  the  upper  end  of  a  compressing  tumor  is  in  the  segment 
corresponding  to  the  highest  zone  of  disturbed  sensation,  or  the  zone 
where  diminished  passes  into  normal  sensation.  Horsley  says  it  is 
necessary  to  very  accurately  determine  the  upper  border  of  the  hyper- 
esthetic  and  paresthetic  zones,  above  the  anesthetic  zone,  and  the  cord 


THE  SPINAL  CORD  571 

should  be  explored  to  the  highest  level  suggested  by  any  definite  symp- 
toms, including  even  slight  paresthesia.  To  allow  for  the  possibility 
of  slight  individual  variation  and  for  any  slight  inaccuracy  in  the  local- 
ization, as  well  as  to  afford  room  for  the  operative  technique,  at  least 
three  laminae  an-  exposed  and  removed. 

The  distance,  if  any,  that  the  afferent  (and  perhaps  the  efferent) 
tracts  run  in  the  cord  before  they  reach  their  real  centres  is  not 
definitely  known.  On  account  of  this  and  of  the  downward  course 
of  the  nerve  roots  from  their  spinal  origin  to  their  exit  from  the  canal, 
and  of  the  downward  passage  of  the  posterior  primary  divisions  of  the 
nerves  to  reach  their  areas  of  distribution,  the  spinal  segments,  and  any 
lesion  compressing  them,  are  at  a  higher  level  than  the  correspond- 
ing segment  zones  on  the  skin  of  the  back.  In  the  dorsal  region 
the  cord  segment  is  10  cm.  (4  in.)  higher  than  the  zone  of  anesthesia 
(Starr).  The  relations  of  the  cord  segments  to  the  vertebral  spinous 
processes  (Fig.  199)  has  been  reduced  by  Chipault  to  the  following 
fairly  accurate  rule:  To  give  the  segment  opposite  a  given  spine,  add 
one  to  the  number  of  the  vertebrae  in  the  cervical  region,  two  in  the 
upper  dorsal  region,  and  three  from  the  sixth  to  the  eleventh  dorsal. 
The  lower  part  of  the  eleventh  dorsal  spine  and  the  space  below  it  are 
opposite  the  lower  three  lumbar  segments.  The  twelfth  dorsal  spine 
and  the  space  below  are  opposite  the  sacral  segments.  In  operations 
for  lesions  of  the  cord  the  knowledge  of  the  relations  of  the  segments  to 
the  spines  and  bodies  of  the  vertebrae  is  absolutely  essential  in  order  to 
know  exactly  where  to  operate,  for  the  localization  of  the  lesion  is  made 
with  reference  to  the  segments,  and  the  spines  are  our  only  landmarks. 
These  relations  are  shown  in  Figs.  198  and  200. 

It  is  most  important  to  remember  that,  as  stated  above,  the  level  of 
the  segment,  or  the  superficial  origin  of  the  nerve  from  the  cord,  is  higher 
than  the  exit  of  the  nerve  through  an  intervertebral  foramen.  In  other 
words,  the  nerve  roots  run  within  the  spinal  canal  and  alongside  of  the 
cord  for  a  distance  which  varies  with  different  nerves  and  increases  as 
we  pa>>  from  the  higher  to  the  lower  segments.  These  nerve  roots  resist 
injury  far  better  than  the  soft  cord,  so  that,  as  a  rule,  the  nerve  roots 
which,  given  oil'  above,  pass  the  site  of  the  cord  lesion  are  seriously 
involved  only  in  the  most  severe  injuries.  It  follows  that,  the  site  of 
the  fracture  being  known,  when  the  level  of  the  anesthesia  extends 
higher  than  would  be  expected  from  the  level  of  the  lesion,  the  lesion 
i  re  b    i<>  crush  the  nerve  roots,  and  hence*  to  completely  sever 

the  cord,  and  the  prognosis  is  correspondingly  bad.      The  nerves  whose 

tool    p. i  -  ;i    spinal  lesion  may  perhaps  show  some  paresthesia,  hyper- 

lesia,  or  pain,  if  they  ;ire    merely   contused    or   compressed,    but    the 

pain,  like  the  anesthesia,  i-  almost  always  referred  to  a  lower  level  than 
the  lesion,  on  account  of  the  intraspinal  course  of  the  nerve  roots,  etc 

I   n.illy  give  rise   to  the  first  symptoms   (nerve-root 

symptoms  I  in  intraspinal  tumor 

On  in  p< ciion  of  the  cuta neon ,  a/reos  of  anesthesia  corresponding 
to  the  several    egmenta  of  the  cord  [Fig.  \W),  it  will  be  seen  that  only 


572 


THE  SPINE 


when  the  first  lumbar  segment  is  involved  does  the  anesthesia  extend  up 
to  the  abdominal  wall.  By  the  area  of  anesthesia  alone  it  is  impossible 
to  definitely  distinguish  severe  lesions  of  the  cauda  equina  from  those 
of  the  segments  from  which  they  are  derived,  for  the  distribution  of  the 
anesthesia  is  practically  identical.  But  most  lesions  of  the  cauda  may 
be  differentiated  from  those  of  the  lower  segments  (p.  573).    In  all  cases 


Fig.  199 


Cutaneous  sensory  distribution  of  the  spinal  segments  on  the  anterior  and  posterior  surfaces, 
from  the  third  cervical  to  the  fourth  sacral,  inclusive.      (After  Kocher.) 

the  localization  of  the  injury  of  the  cord  must  be  made  from  the  symp- 
toms observed  shortly  after  the  injury,  for  within  a  few  days  myelitis 
is  apt  to  occur  and  cause  an  upward  extension  of  the  area  of  anesthesia 
and  paralysis. 

For  the  interpretation  of  the  muscular  paralysis  three  methods  of  de- 
termining the  segments  which  correspond  to  the  nerve  supply  of  the 
muscles  have  been  employed:  (1)  the  experimental,  on  monkeys;  (2)  the 


THE  SPINAL  CORD  573 

clinical,  from  an  accurate  observation  of  cases;  and  (3)  the  anatomical) 
from  minute  dissections.  Although  perhaps  less  accurate  than  the  others, 
the  clinical  method  is  still  of  the  most  practical  service,  and  hence  column 
D,  Fig.  200,  gives  the  results  obtained  by  Thorburn  from  an  analysis 
of  careful  clinical  observations. 

According  to  Thorburn  no  motor  supply  comes  from  the  first  and 
second  lumbar  segments,  but  many  derive  a  part  or  the  whole  of 
the  nerve  to  the  cremaster  from  them.  The  paralysis  which  serves 
in  the  localization  of  an  injury  is  that  of  the  muscles  whose  nuclei 
are  in  the  uppermost  segment  involved  by  the  lesion,  hence  it  is  a 
flaccid  paralysis  with  rapid  atrophy,  as  its  trophic  centres  (nuclei) 
are  involved.  It  will  be  seen  that  motor  paralysis  is  slight  in  the  lower 
cord  lesions,  only  the  perineal  muscles,  bladder,  and  rectum  being 
involved  in  lesions  just  below  the  second  sacral  segment,  and,  with  the 
possible  exception  of  the  glutei,  only  the  leg  and  foot  muscles  are  affected 
in  addition,  if  the  lesion  involves  all  the  sacral  segments. 

In  pressure  lesions  of  the  cauda  equina,  on  the  other  hand,  the  pressure 
may  be  sufficient  to  cause  widespread  paralysis  when  sensation  is  but 
slightly  affected.  Hence  in  a  lesion  of  the  cauda  equina  the  distribution 
of  the  paralysis  may  be  much  more  extensive  than  would  be  expected 
from  the  distribution  of  the  anesthesia,  while  in  lesions  of  the  cord  the 
distribution  of  the  two  usually  correspond.  In  cauda  equina  lesions  the 
symptoms  are  less  likely  to  be  symmetrical  in  distribution  than  in  lesions 
of  the  conus  terminalis,  and  severe  pain  is  more  common  than  in 
lesions  of  the  cord.  Muscular  atrophy  accompanies  the  paralysis,  for 
the  muscles  are  cut  off  from  their  trophic  centres  in  the  anterior  horn. 
As  the  pressure  increases  the  reflex  arc  is  broken  and  the  reflexes  are  lost. 
Also  in  pressure  lesions  of  the  cauda  equina  the  nerves  which  pass  out 
lower  down  are  first  and  most  seriously  involved,  though  they  are  situated 
nearer  the  centre  and  would  appear  to  be  less  exposed  to  pressure,  a 
fact  that  is  not  explained.  The  cauda  equina,  formed  by  the  nerve  roots 
of  the  lumbar  and  sacral  segments,  covers  and  conceals  the  lower  end 
of  the  cord,  so  that  no  injury  of  the  lumbosacral  region  of  the  latter 
can  occur  without  an  injury  of  the  cauda,  which  may  also  be  injured 
below  the  level  of  the  cord.  The  sacral  roots  of  the  cauda  have  an  intra- 
spinal course  of  12.5  to  15  cm.  (5  to  6  in.).  The  dura,  which  encloses 
the  cauda  like  a  muff,  is  pierced  by  the  roots  opposite  the  foramina  by 
which  they  emerge. 

According  to  Starr  the  control  of  the  bladder  and  rectum  is  always  lost 
together.  It  is  losi  if  the  fourth  and  fifth  sacral  segments  are  involved, 
in  which  are  the  centres  controlling  these  organs.  In  a  lesion  involving 
these  reflex  centres  the  reflex  arc  is  broken  ami  absolute  passive  incon- 
tinence follows  temporary  retention;  the  bladder  first  distends  and  then 

dribbles  from  overdistention.  The  rectum  shows  no  tendency  (<»  empty 
ii  elf.     /"  a  lesion  above  these  centres  the  cerebral  inhibitory  control  is 

ent  oil'  §0  that,  after  ;i  temporary  retention  due  to  shock,  the  bladder  and 
rectum  an  emptied  at  frequent  intervals  unconsciously  and  involuntarily. 

The  reflex  mechanism  being  intact  works  like  a  dock  without  a  pendu- 


574  THE  SPINE 

lum.  This  is  known  as  active  incontinence.  Similarly  in  lesions  above 
the  reflex  centre  of  erection  of  the  penis,  which  is  in  the  first  three  sacral 
segments  the  inhibitory  fibers  are  cut  off  and  a  chronic  erection  {pria- 
pism) usually  occurs. 

Thorburn  has  called  attention  to  the  pathognomonic  posture  assumed 
in  lesions  just  below  the  fifth  cervical  segment  and  the  explanation  of  it. 
The  arms  are  abducted  by  the  deltoid,  and  rotated  out  by  the  supra-  and 
infraspinati,  the  elbows  are  flexed  by  the  brachialis,  brachioradialis, 
and  biceps,  and  the  hand  is  supinated  by  the  latter,  all  the  other  muscles 
of  the  arm  being  paralyzed.  Such  a  position  is  assumed  because  the 
muscles  controlled  by  the  nerve  cells  just  above  the  lesion,  which  causes 
the  paralysis,  are  actively  contracted  by  the  condition  of  irritation  into 
which  these  nerve  cells  are  thrown.  As  the  phrenic  nerve  is  derived  prin- 
cipally from  the  fourth  cervical  segment,  receiving  contributions  from  the 
third  and  fifth  segments,  lesions  at  or  above  this  level  are  rapidly  fatal 
from  failure  of  respiration.  In  lesions  between  this  and  the  upper 
thoracic  segments  the  respiration  is  entirely  diaphragmatic.  Thus  the 
higher  the  lesion  in  the  cord  the  more  serious  is  the  prognosis.  As  the 
ciliospinal  centre,  whose  stimulation  causes  the  pupil  to  contract, 
extends  from  the  sixth  cervical  to  the  third  thoracic  segment,  and  its 
fibers  leave  the  cord  to  join  the  sympathetic  with  the  eighth  cervical 
and  first  thoracic  roots,  an  irritative  lesion  of  or  above  the  first  thoracic 
segment  causes  a  narrowing  of  the  pupil  on  the  same  side  and  perhaps 
profuse  sweating  of  that  side  of  the  face  and  neck. 

The  integrity  of  the  spinal  reflexes  depends  upon  that  of  the  afferent 
sensory  nerve,  the  efferent  motor  nerve,  their  connection  in  the  gray 
matter  of  the  cord,  and  the  inhibitory  fibers,  descending  in  the  crossed 
pyramidal  tracts,  by  which  the  brain  regulates  the  reflexes.  If  the  latter 
fibers  are  destroyed  by  a  lesion,  all  reflexes  below  this  point  are  exag- 
gerated from  the  loss  of  cerebral  control.  If  the  afferent  or  efferent 
nerves  or  their  association  in  the  gray  matter  is  destroyed,  the  reflex  arc 
is  broken  and  the  reflexes  are  lost.  The  reflexes,  with  the  segments  to 
which  they  correspond  clinically,  are  given  in  column  F,  Fig.  200. 

Hemorrhage  may  occur  within  the  cord  (hematomyelia)  or  within  the 
membrane  (Jiematorrhachis).  The  latter  may  extend  the  length  of 
the  cord  or  gravitate  largely  to  the  lower  end,  and  produces  no  very 
localized  symptoms.  It  almost  never  exists  as  an  independent  lesion. 
According  to  Thorburn,  hematomyelia  is  not  at  all  uncommon,  and 
occurs  principally  between  the  fourth  cervical  and  the  first  thoracic 
segments  (inclusive),  corresponding  to  the  cervical  vertebrae  from  the 
fourth  to  the  seventh  inclusive.  This  is  the  summit  of  the  cervical 
curve,  where  an  acute  bend  of  the  neck  would  make  itself  mainly  felt. 
In  fact,  the  cord  has  been  crushed  by  such  a  bend  without  fracture,  and 
with  only  temporary  diastasis.  The  hemorrhage  is  generally  due  to  an 
overstretching  of  the  cord,  in  which  the  central  gray  matter  is  the  chief 
seat  of  the  lesion,  for  it  is  softer  and  more  easily  injured,  though  better 
protected,  than  the  white  columns.  The  symptoms  produced  by  such  a 
hemorrhage  depend  upon  (1)  a  compressing  and  (2)  a  destroying  lesion; 


Fir;.  200 


D. 

E. 

F. 

MOTOR 

SENSORY 

REFLEXES 

DISTRIBUTION. 

AREAS. 

/ABDOMINAL. 


CREMASTERIC 


FOOT  CLONUS. 


Topography  and  distribution  of  the  spinal  nerve  roots.  The  brackets  in  column  A  show  the 
extreme  limits  between  which  in  different  subjects  examined  by  Reid  each  group  of  nerve  roots 
was  found  to  arise.  Column  B  shows  each  nerve  cut  off  at  the  level  of  its  intervertebral  fora- 
men, thus  showing  the  obliquity  of  its  course  in  the  neural  canal.  Column  C  gives  the  vertical 
distance  in  millimeters  which  in  Testut's  case,  of  a  subject  eighteen  years  of  age,  separated  the 
superficial  origin  of  each  of  the  nerves  marked  from  its  intervertebral  foramen. 


576  THE  SPINE 

the  former  temporary  and  causing  paralysis,  disassociated  anesthesia 
(thermo-anesthesia  and  analgesia  without  tactile  anesthesia),  loss  of 
control  of  the  reflexes  of  the  bladder,  rectum,  penis,  etc.;  the  latter 
permanent  and  causing  atrophic  paralysis,  and  perhaps  anesthesia,  of 
the  parts  supplied  by  some  of  the  roots  of  the  brachial  plexus.  These 
hemorrhages  are  usually  confined  to  and  most  severe  in  the  centre  of  the 
cord,  so  that  the  more  peripheral  fibers,  which  emerge  near  the  lesion, 
may  not  be  affected  by  the  eccentric  pressure,  while  the  more  central 
fibers,  which  emerge  lower  down,  are  more  and  more  affected;  hence  the 
area  of  anesthesia  is  ill  defined  and  may  be  far  below  the  seat  of  the 
lesion.  Some  doubt  is  thrown  on  the  correctness  of  this  explanation  by 
the  fact,  stated  by  Horsley,  that  the  same  tendency  to  involve  the  lowest 
sensory  fibers  first  is  found  in  the  case  of  tumors,  whose  pressure  is 
concentric.  In  tumors  the  invasion  of  paralysis  is  from  above  down- 
ward, or  the  reverse  of  that  of  anesthesia.  The  favorite  situation  for 
tumors  is  below  the  middle  of  the  cervical  region  and  at  the  upper 
and  lower  ends  of  the  thoracic  region. 

Operations  upon  the  cord,  in  addition  to  those  for  fracture  disloca- 
tions, are  not  infrequently  done  for  tumors,  or  inflammatory  deposits, 
the  operator  being  guided  by  the  above  and  other  minor  points  of 
localization.  The  cord  is  first  exposed  by  a  laminectomy.  Such 
operations  have  been  very  successful  when  the  tumor  has  been  removed 
and  the  operation  was  not  too  long  deferred. 


INDEX. 


Abdomen,  266 

axis  of,  266,  317 
bloodvessels  of,  391,  392 

extraperitoneal  anastomosis  of, 
391,  392 
blows  on,  276,  282 
boundaries  of,  267 
cavity  of,  317 

congenital  deformities  of,  275,  282 
injuries  of,  282 
lymphatics  of,  279,  392 
muscles  of,  271 
operations  on,  283-285 
regions  of,  286 
shape  of,  266 
skin  of,  269 

surface  markings  of,  267 
topography  of,  287 
wounds  of,  282 
Abdominal  aneurysm,  391 
aorta,  391 
ascites,  318 
cavity,  317 
ring,  external,  291 
internal,  292 
tumors,  240,  246,  339 
viscera,  323 

nerves  of,  392 
wall,  abscess  of,  272,  273 
anterior,  269 

aponeurosis  of,  273 
Mow-  on,  276,  282 
deformities  of,  275,  282 
fascia  of,  269,  270 
incisions  in,  280,  283-285 
lymphatics  of,  279 
musclee  of,  271 
nerves  of,  279  281 
reflexes  of,  281 
posterior,  .'507 
subperitoneal  tissue  of,  277 

I-  of,  278 
wounds  of,  282,  :'.I7,  318 
abdominal  w.- ill.  272,  _'?.; 
in  .-nit  rum  of  Highmore,  89 
:il  eolar,  1 12 
llary,  187 
w.i  I,  158 
gluteal.  is7 
"i  hip-joint,  199 
iliac,  801,  307,  -''.I-' 
87 


Abscess,  intercostal,  232 
ischiorectal,  416,  483 
of  liver,  356,  362,  363 
lumbar,  314 
mammary,  236 
in  mastoid  antrum,  63 
mediastinal,  230 
orbital,  79 
palmar,  218 
parotid,  101,  102 
pelvic,  275,  30S,  407,  445 
perinephritic,  315,  381,  382,  384 
perityphlitis  308 
plantar,  543 
popliteal,  515 
prostatic,  410,  427 
psoas,  301,  302,  311 
renal,  382,  384 

retropharyngeal,  101,  126,  127,  158 
of  sacro-iliac  joint,  396 
in  scalp,  23 

in  sheath  of  rectus,  273 
spinal,  556 

subdiaphragmatic,  323 
in  temporal  fossa,  25 
in  testis,  470 
Accommodation,  76,  77 
Acetabulum,  486,  494,  495 
Acromion  process,  163-164 

fractures  of,  172 
Acromioclavicular  joint,  170,  173 
dislocation  of,  170 
movements  of,  171 
Acromiothoracic  artery,  165,  171,  174 
Adductor  longus,  490,  492-493,  509 
rupture  of,  492 
magnus,  509 
tubercle,  512 
Adenoids,    128 

Adrenals,  :'»!») 

relal  ions  of,  390 
Air  in  veins,  133,  I  12,  159 
Uderman's  nerve,  55 
Alveolar  abscess,  112 
Ampulla  of  Vater,  371 
Amputation.    See  Special  part. 
\n.-il  fascia,  M)6,  17'.),  483 

triangle,  183 
omo  es  about  elbow,  197 

of  vessels  of  abdomen,  279,  391-392 
Aneurysm.    See  Special  art 
Angular  ourval  ure  of  spine,  556 
Inkle,  531 


578 


INDEX 


Ankle,  fascial  of,  533-534 
joint,  535 

dislocations  of,  536 
effusions  into,  531,  535-536 
excision  of,  539 
fractures  about,  537 
lateral  motion  in,  535 
sprains  of,  536,  538 
surface  markings  of,  531 
tendons  about,  531,  532 

sheaths  of,  534 
topography  of,  532 
Ankylosis  of  hip,  312,  557 

of  jaw,  109 
Annular  ligaments  of  ankle,  533 

of  wrist,  209,  211 
Anorectal  groove,  411 
line,  411,  413,  414 
Anteflexion  of  uterus,  433 
Anterior  crural  nerve,  493 

paralysis  of,  552 
tibial  artery,  526,  528,  531-532,  540 
Anteversion  of  uterus,  433 
Antrum  of  Highmore,  85,  89 
empyema  of,  89,  113 
mucosa  of,  90 
orifice  of,  90 
relations  of,  89 
tumors  of,  90 
mastoid,  60.     See  Mastoid  antrum, 
pylori,  324 
Anus,  415 

artificial,  343 
development  of,  416 
epithelioma  of,  413 
fissure  of,  416 
fistula  of,  416 
imperforate,  416 
sphincters  of,  411 
Aorta,  abdominal,  391 
arch  of,  257 
relations  of,  257 
thoracic,  259 
variations  of,  259 
Aortic  aneurysm,  257-259,  391 
orifice,  254 
plexus,  392 
Apex  beat,  254 
Aphasia,  44 

Aponeuroses,  abdominal,  273 
Appendices  epiploic^,  354 
Appendicitis,  349,  350,  351 
Appendiculo-ovarian  ligament,  350 
Appendix  vermiformis,  348.      See  Vermi- 
form. 
Aqueduct  of  Fallopius,  59,  60 
Arachnoid,  40 
Arches  of  foot,  544-545 
Argyll-Robertson  pupil,  77 
Arm,  190 

abduction  of,  177 
amputation  of,  191,  193 
arteries  cut  in,  193 
fascia  of,  191 
nerves  of,  191,  192 
skin  of,  191 


Arm,  surface  markings  of,  190 

topography  of,  190 
Arnold's  nerve,  55 
Arteries.     See  Special  artery. 
Arteriomesenteric     obstruction     (ileus), 

337 
Arteriovenous  aneurysm,  39,  196 
Aryteno-epiglottic  folds,  146-147 
Arvtenoid  cartilages,  147,  148 
Ascites,  318,  319,  364 
Aspiration  of  air  in  veins,  142 
Asterion,  26 
Asthma,  248 
Astragalus,  535-536,  539-540,  544-547 

dislocations  of,  548-549 

fracture  of,  551 
Atlas,  126,  130,  554 
Auditory  canal,  external,  53 
relations  of,  55 

centre  of  cortex,  45 
Auricle,  left,  253,  254 

right,  253-256 
Auricles,  supernumerary,  52,  162 
Auriculotemporal  nerve,  55,  102 
Auriculoventricular  groove,  254 
Axilla,  165,  185 

boundaries  of,  185 

contents  of,  187 

exposure  of,  189 

suspensory  ligament  of,  171 
Axillary  abscess,  187 

incision  of,  187 

aneurysm,  182,  188 

artery,  164,  165,  172,  179,  182,  187 
course  of,  165,  187 

fascia,  187 

line,  229 

lymph  nodes,  165,  188,  189 

vein,  172,  182,  187,  188 
Axis,  130,  554 
Azygos  major  vein,  250,  260 


B 


Bartholin,  glands  of,  452 
Barton's  fracture,  212 
Basador's  operation,  139 
Base  of  skull,  fracture  of,  31 
Basilic  vein,  196 
Biceps,  grooves  along,  190,  194 

cubiti  tendon,  175, 176, 179,  194-195, 
198 
dislocation  of,  176 
femoris  tendon  in  ham,  513,  515 
tenotomy  of,  515 
Bichat's  lobule,  99 
Bicipital  fascia,  194-196 
Bile  duct,  common,  course  of,  335-336, 
370 
obstruction  of,  372 
operations  on,  372 
relations  of,  321,  335,  336, 
370,  373 
Biliary  colic,  372 
Bladder,  417 


INDEX 


579 


Bladder,  capacity  of,  417 

of  child,  424 

development  of,  425 

distention  of,  41S,  422-423,  573 

double,  421 

extroversion  of,  282 

fasciculated,  421 

female,  424 

fixation  of,  421 

hernia  of.  421 

interior  of,  423 

ligaments  of,  405,  421 

malformations  of,  282,  425 

mucous  membrane  of,  422 

nerves  of,  422,  57:^  _ 

new  growths  of,  425 

outlet  of,  418,424 

position  of,  418 

puncture  of,  410,  419 

relation  of,  to  peritoneum,  418 

relations  of,  408,  409,  410 

rupture  of,  420 

sacculated,  421 

shape  of,  418 

sphincter  of,  421,  428 

st  ructure  of,  421 

vessels  of,  422 

wall  of,  421 

wounds  of,  419,  420 
Blepharospasm,  00 
Bloodvessels  of  abdomen,  391,  392 

of  abdominal  wall,  278 

of  arm,  191 

of  brain,  41,  42 

of  breast,  237 

of  buttock.  486 

of  elbow,  105-196 
ice,  91 

of  foot,  540,  542 

of  forearm,  205 

of  band,  220 

ot  knee,  513,  515,  516 

Oi  leg,  520-528 

of  neck,  133,  134,  136,  13S-141 

of  nose,  86 
of  orbit,  78 

alate,  120,  122 
of  pelvis,  106 
of  red oiii,  i  L3 
dp,  20,  21 
Scarpa's  triangle,  190,  193 
houMer,  172,  1S7_,  188 
of  spermatic  cord,  172   1/  I 
ot  thigh,  509,  510 
ot  t  \  mpanic  membrane,  58 
Bowlegs,  r,M> 

Brachial  artery,  190,  L91.  195 
abnormalities  of,  L92 
:i 1 1< ■  1 1 r  *.  -iii  of,  L95  1 96 
compression  of,  L92,  105 
lit_';it ure  of,  191 

line  Of,    101 

in  phlebotomy ,  I'm; 

i.   101 

plexus,  134,  135,  l  15,  168,  225 
Brachialu,  L91    192,  L98,  L90 


Brachiocephalic  arterv,  259 

vein,  150,  258-260 
Brachioradialis,  191-192,  205,  207 
Brain,  41 

blood  supply  of,  41-42 
centre  of  sensation  of  sound,  45 
of  taste  and  smell,  45 
visual,  45 
compression  of,  42 
cortical  centres  of,  42 
decompression  of,  42 
fissures  of,  46-50 
functions  of,  localization  of,  42 
membranes  of,  33 
motor  area  of,  42 

mental  or  association  centres  of,  46 
pulsation  of,  35 
relations  of,  to  skull,  46 
sensory  cortical  area  of,  44 
speech  areas  of,  44-45 
Branchial  arches,  161 
clefts,  161 
fistula;,  162 
Branchiogenic  cysts,  162 
Breast,  234 

abnormalities  of,  238,  490 
abscess  of,  236 
arteries  of,  237 
cancer  of,  188-189,  238 
capsule  of,  234 
lymphatics  of,  188-189,  237 
nerves  of,  237 
removal  of,  238 
Bregma,  26 

Broad  ligament,  432,  436,  444 
borders  of,  444,  445 
contents  of,  444 
cysts  of,  445 

relations  of,  444-445,  448 
Broca's  convolution,  44,  45 
Bronchi,  248-251,  257,  258 

foreign  bodies  in,  249,  251 
Bronchial  lymph  nodes,  250 
Bronchiectasis,  248 
Bronchocele,  152,  155 
Brunner's  glands  in  burns,  336 
Bryant's  line  and  triangle,  486 
Bubonocele,  294 
Buccal  nerve,  97 

excision  of,  07 
Buccinator,  07,  98,  00 
Bulb,  artery  of,  477,  I7X-170 

of  corpus  spongiosum,  164,  177,  178 
170,  is  I 
Bulbi  vestibuli,  lis.  452 
Bulbous  portion  of  urethra,  155 
Bunion,  5 13 
Bursas  aboul  ankle,  535 

elbow,    107 

bam,  516,  517 

knee  joinl ,514 

shoulder,  L75  177 
beneath  psoas,  192,  195 
over  greal  '  rochanter,  488 

I uber  iseliii,  394,  188 
prepatellar,  514 


580 


INDEX 


Bursas,  subacromial,  175 

thyrohyoid,  144 
Bursting  fractures  of  skull,  31,  32 
Buttocks,  485 

fascia  of,  487 

fold  of,  485 

lymphatics  of,  489 

nerves  of,  486-487 

surface  markings  of,  485 

topography  of,  486 

vessels  of,  486 


Calcaneo-astragaloid  joint,  540,  547 
Calcaneoscaphoid  ligament,  inferior,  540, 

545  546 
Calcaneum,  533,  535,  539,  542-544,  547, 
551 
fracture  of,  551 
Canal  of  Nuck,  300,  446 
Canaliculi,  70 
Cancrum  oris,  91 
Capsule  of  Glisson,  364 
of  Tenon,  73 

prolongations  of,  74 
Cardiac  flatness,  area  of,  253 
incisure,  245,  253 
orifice  of  stomach,  324-325 
Carotid  artery,  common,    130,    139,    150, 
259-260 
aneurysm  of,  139 
ligature  of,  140 
line  of,  137 

relations  of,  140,  259,  260 
wounds  of,  140-141 
external,  102,  136,  141 

differentiation   from   inter- 
nal, 142 
excision  of,  141 
in  operations  on  tonsil,  124 
ligature  of,  141 
internal,  39,  102,  128,  142 

in  operations  on  tonsil,  124 
body,  141 

sheath,  140,  153,  157 
triangles,  139 
tubercle,  130,  140,  554 
Carpometacarpal  joints,  216 
Caruncle,  lacrymal,  69 

urethral,  451 
Castration,  466,  472,  473 
Catheterization  of  Eustachian  tube,  64-65 
of  ureters,  447 
of  urethra,  455,  460 
Cauda  equina,  570,  573 
Cava,  inferior,  362,  371,  373,  380,  389 

superior,  250,  256,  2S8,  260 
Cavernous  sinus,  39,  69 
Cavum  Retzii,  278,  419 
Cecum,  344 

descent  of,  345 
foreign  bodies  in,  346 
forms  of,  344 
hernia  of,  345 


Cecum  in  intestinal  obstruction,  346 
position  of,  345 
relation  of,  to  peritoneum,  346 
Celiac  axis,  391 
Cephalhematoma,  30 
Cephalic  vein,  164, 171, 172, 184, 188, 190, 

196 
Cephaloceles,  27 
Cerebellum,  38,  46 
Cerebral  localization,  42-46 
Cerebrospinal  fluid,  31,  32,  41,  486,  559, 
560,  564 
composition  of,  565 
normal  pressure  of,  564 
Cervical  abscess,  158-159 

fascia,  deep,  136,  149,  155,  156-159 

layers  of,  157 
lymph  nodes,  159-161 
nerves,  131-132 
ribs,  135 

sympathetic,  143 
triangle,  anterior,  135 

posterior,  132 
vertebra;,  554,  556,  558-560,  574 
Cervix  uteri,  432,  435 
canal  of,  437 
elongation  of,  435 
external  os  of,  432,  435 
fixation  of,  432 
relation  of,  to  ureters,  436 
zones  of,  435 
Cheeks,  91 
Chest.     See  Thorax. 
Choked  disk,  79 
Cholecystectomy,  369 
Cholecystenterostomy,  335,  356,  369 
Cholecystotomy,  369 
Choledochotomy,  372 
Chopart's  amputation,  550 
Chorda  tympani  nerve,  57,  59,  92,  118 
Chordee,  464 
Circle  of  Willis,  140 
Circumflex  arteries,  165,  174,  185 
nerve,  165,  174,  182,  184-185 
Circumcision,  462 
Cirrhosis  of  liver,  364 
Cirsoid  aneurysm,  21 
Clavicle,  163 

dislocations  of,  169 
excision  of,  168 
fractures  of,  166-168 

complications  of,  168 
displacement  of,  166 
green-stick,  167 
reduction  of,  168 
periosteum  of,  167,  168 
relations  of,  168 
Clavipectoral  fascia,  157,  171,  185-186 
Cleft  palate,  122-123 
Clitoris,  452 
Club  foot,  534,  545 
Coccydynia,  395 
Coccygeus,  404,  406,  483 
Coccyx,  excision  of,  395 
fracture  of,  395 
tip  of,  394 


INDEX 


581 


Cock's  operation,  410 

Colles'  fracture,  209,  211,  212-213 

Colon,  353 

ascending,  355 

capacity  of,  353 

characterized  by,  354 

descending,  355 

diverticula  of,  354 

hepatic  flexure  of,  356 

mesentery  of,  355 

sigmoid,  357 

mesentery  of,  357 

splenic  flexure  of,  356 

stricture  of,  353 

transverse,  320,  356 

tube,  358 
Colotomv,  inguinal,  358 

lumbar,  354-355,  358 
Commissure,  posterior,  451 
Compression  fractures  of  skull,  31,  32 

of  brain,  40 

of  cord,  566 
Compressor  urethra?,  454,  459,  478 
Concussion  of  brain,  40 

of  cord,  566 
Condylar  vein,  posterior,  38 
Condyles  of  femur,  512,  517,  518 

of  humerus,  194,  195 

fractures  of,  201-203 

of  jaw,  106-108 
Congenital  clubfoot,  547 

dislocation  of  hip,  503,  551 

hernia,  295 

hydrocele,  470 

malformations  of  anus,  416 
of  bladder,  282,  425 
of  penis,  465 

torticollis,  131-132 
Conjoined  tendon,  271-272,  290,  292 

<  lonjuncl  n  a,  08—69 

Constrictors  of  pharynx,  122,  124,  127 
Contrecoup,  fracture  by,  32 

contusions  due  to,  41 
Convolutions  of  brain,  centres  of,  42-46 
Coraco-acromial  arch,  176 

ligament,  165,  173,  184 
obrachialis,  105,  178,  192 
Coracoclavicular  ligament,  L70,  173 

<  loracoid  procec  -.  164,  1 7" < v  177 

fractures  of,  17:; 
Cord,  spermatic,  292  293,  304 
hydrocele  of,  ill.  170 

i i.i I,  563 

compression  of,  566 
concussion  of,  566 
ocal,  l  16  1  18 
•  oronal  sul  ure,  26,  50 
no  mi-.  1 10 
Coronoid  process  of  jaw,  107,  loo,  112 

r.i  ulna,  L95,  200,  204 
« !orp  'mi,  lo  1 

luteum,  1 10 

1 1 1 1 .    Mil 

:  uin,  function  o 
n  l.f.  icular  line,  376 


Costocoracoid  membrane,  171,  188 
Costomediastinal  sinus,  243 
Costophrenic  sinus,  240,  243,  360,  378 
Cotyloid  ligament,  496-497,  506-5U7 
Cowper's  glands,  454,  477^478 
Coxa  vara,  506 
Coxitis,  497-499 
Craniectomy,  18,  26 
Craniocerebral  topography,  46 
Craniotabes,  27 

Cranium,  bony  landmarks  of,  25 
Creases  of  palm,  215 

of  wrist,  209 
Cremaster  muscle,  293,  467 
Cremasteric  artery,  467 

fascia,  293,  466 

reflex,  467,  494 
Cretinism,  154 
Cribriform  fascia,  305,  490,  492 

plate,  80,  83,  86 
Cricoid  cartilage,  129,  130 

fracture  of,  148 
Cricothyroid  membrane,  149 

space,  129 
Cricotonry,  149 
Crura,  lesions  of,  46 
Crural  arches,  276,  302,  304 

canal,  302,  305-306,  492 

nerve,  anterior,  493 

ring,  302-305,  492 

sheath,  276,  302 
Crutch  paralysis,  192 
Cubital  fossa,  194,  196 
Cubitus  varus,  202,  203 
Cuboid  bone,  539 
Cuneiform  bones,  209,  548-549 
Curvature  of  spine,  228,  556,  558 
( 'urves  of  spine,  555,  556 
(Jut-throat  wounds,  144,  145 
Cystic  duct,  369 

obstruction  of,  369 
Cystocele,  447 
Cystotomy,  perineal,  479-481 

suprapubic,  408,  419 
Cysts,  dermoid,  05,  395-396,  441 


DABTOS,   151,  462,  466 
Deglutition,  121,  129 
Deltoid  muscle,  171,  175,  179,  184-185, 
I '.to 

region,  l  <  I 

tubercle,  L63 
l  fental  nerve,  inferior,  07 
Dentition,  11:'. 
I  »e  cendens  noni,  1  1 1 

i  ling  palai in'-  artery,  120,  122 
I  diaphragm,  239 

level  of,  I'll) 

malformal  ion  of,  239 

openings  in,  2 10 

wounds  of,  2  H> 
l  tiaphragmal  i<-  hernia,  239 
Digastric  muscle,  135,  137,  130 


582 


INDEX 


Diploe,  veins  of,  22 

Diplopia,  76,  77 

Direct  inguinal  hernia,  296 

Dislocations.     See    Several    bones     and 

joints. 
Dorsal  vein  of  penis,  406,  459,  463,  479 
Dorsalis  pedis  artery,  532,  535,  540 

scapulae  artery,  165,  173 
Douglas,  curved  line  of,  275 

pouch  of,  409,  434,  435,  448 
Drop-wrist,  192 
Ducts  of  Bartholin,  119 

of  Muller,  438,  443,  472 

of  Santorini,  374 

thoracic,  258,  259,  261,  264 

of  Wirsung,  374 
Duodenal  fossa,  337 

papilla,  336,  371 

ulcer,  336 
Duodenojejunal  fossa,  337 
Duodenum,  334 

crescentic  fold  of,  336 

mobilization  of,  336 

position  of,  334-337 

relations  of,  335-337 
Dupuvtren's  contracture,  218 
Dura,' 33 

arteries  of,  34 

at  base  of  skull,  35 

of  cord,  564 

outer  layer,  adhesion  of,  to  bone,  34 

processes  of,  36 

sinuses  of,  36 

mechanism  to  prevent   aspira- 
tion of,  38 


Ear,  52 

bleeding  from,  in  fracture  of  base,  33 

coughing,  56 

development  of,  52 

external,  52 

fissures  of,  52 

foreign  bodies  in,  54,  55 

frostbite  of,  52 

hematomata  of,  52 

lymphatics  of,  65 

middle,  58 

nerves  of,  55 

specula,  54 

watery  discharge  from,  33 

yawning,  56 
Ectopia  testis,  469 
Ectropion,  66,  70 
Edema  of  evelids,  67 

of  glottis,  147,  148 

of  hand,  217 

of  scrotum,  466 
Ejaculatory  ducts,  428,  453 
Elbow,  194 

bursa  behind,  197 

dislocations  of,  199-200 
•     reduction  of,  200 

excision  of,  198-199 


Elbow,  fold  of,  194 

fractures  about,  201-204 
joint,  197 

ankylosis  of,  198 
effusions  into,  197 
region,  194 
suppuration  in,  198 
surface  markings  of,  194 
topography  of,  195 
Elephantiasis,  468 
Emissary  veins  of  skull,  21 
Emphysema,  168 

subcutaneous,  245,  249 
Empyema,  231 
Encephalocele,  27 
Encysted  hydrocele  of  cord,  295 
Ensiform  cartilage,  230,  267 
Enterotomy,  343 
Entropion,  66,  68,  70 
Enucleation  of  eyeball,  75 
Epididymis,  471 " 

globus  major  of,  471 
minor  of,  471 
Epididymitis,  471 
Epigastric  region,  287 

vein,  superficial,  269,  279 
vessels,  deep,  275,  278,  293,  297-298, 
304 
Epiglottis,  129,  144-145,  146,  148 
Epilepsy,  cervical  sympathetic  in,  143 
Epiphora,  70 

Epiphysis  of  acromion,  separation  of,  172 
of  femur,  lower,  512 

in  excision  of  knee,  524-525 
in  knock-knee,  517 
separation  of,  525 
upper,  separation  of,  498,  506 
of  fibula,  539 

of  humerus,  separation  of,  183-203 
of  radius,  214 

of  third  phalanx,  in  whitlow,  222 
of  tibia,  524,  525,  538-539 
Epipteric  bone,  27 
Epispadias,  465 
Epistaxis,  81,  86 
Episternal  notch,  130 
Epitrochlear  node,  197 
Epulis,  113 

Erector  spina?,  312,  314 
Eruption  of  teeth,  113 
Esophagotomy,  265 
Esophagus,  262 
caliber  of,  263 
cancer  of,  264 
constrictions  of,  263,  264 
direction  of,  262 
diverticula  of,  265 
foreign  bodies  in,  263 
length  of,  262 
operations  on,  265 
stricture  of,  263 
relations  of,  258,  259,  264 
Estlander's  operation,  231 
Eustachian  tube,  63,  161 

catheterization  of,  64-65 
direction  of,  63 


INDEX 


583 


Eustachian  tube  in  infants,  63 
obstruction  of,  64 
pharyngeal  orifice  of,  64,  82,  84, 
121,  128  _ 
Excision.     See  Special  parts. 
Exophthalmic    goitre,    cervical    sympa- 
thetic in,  143,  155 
Exophthalmos,  72 
External  abdominal  ring,  291 

angular  process  of  frontal  bone,  25, 

65 
auditory  canal,  53 

abscess  of,  54 

cartilaginous  portion  of,  54 
diameters  of,  54 
direction  of,  53 
foreign  bodies  in,  54,  55 
nerve  supply  of,  55 
polypi  of,  54 
relations  of,  55 
skin  of,  54 
carotid  artery,  102 

in  operations  on  tonsil,  124- 
125 
cutaneous  nerve,  191,  196 
iliac  artery,  308-309 

lymph  nodes,  310 
mammary  artery,  165,  188,  237 
oblique  muscle,  269,  271 
spermatic  fascia,  271,  291 
Extra-uterine  pregnancy,  442-443 
Extravasation  of  urine,  270,  463,  476-477 
Extroversion  of  bladder,  282,  425 
Eyeball,  enucleation  of,  74,  75 
Eyebrows,  65 
Eyelids,  66 

arteries  of,  69 

canthi  of,  67,  68-69 

caruncle  of,  69 

edema  of,  67 

epithelioma  of,  66 

foreign  bodies  beneath,  68,  69 

fornix  of.  68 

free  borders  of,  69 

layers  of,  66  69 

skin  tit',  66 

"stye"  of,  60 


IV  b,  65,  90 

di-\ elopmenl  of,  ill,  122 

cia  of,  97 
incision*  on,  97 
nerves  of,  92 

-kin  Of,  '.»')  91 

Facial  artery,  91,  126,  L36 
canal,  60 

of,  o:s 
nerve,  86,  92,  102,  103 
anastomosis  in,  03 
paral)  lis,  60,  02,  03 

in  fractures  ol  ba  e  of    Icull,  03 
vein,  01.  L36,  I  M 
I  allopiao  tube,  1 1 1^ 


Fallopian  tube,  blood  supply  of,  443 
course  of,  442 
development  of,  443 
fimbriated  extremity  of,  442,  443 
mucosa  of,  443 
operation  on,  443 
Fascia,  abdominal,  269,  270 
anal,  483 
of  ankle,  433,  434 
of  arm,  191 
axillary,  187 
bicipital,  194-196 
of  buttocks,  487 
cervical,  136 

clavipectoral,  157,  171,  185-186 
cribriform,  490 
of  deltoid  region,  174 
of  foot,  533,  542,  546,  547 
iliac,  276,  277,  301,  302,  310 
lata,  302,  304,  492,  509 
of  leg,  527 
lumbar,  314 

obturator,  405,  479,  483 
orbital,  73-74 
of  palm,  218 
palmar,  218 
parotid,  99 

pectoral,  171,  185,  235-236 
pelvic,  405 
of  penis,  463 
perineal,  476 

plantar,  533,  542,  546,  547 
popliteal,  515 
prevertebral,  157 
rectovesical,  406,  421,  479 
of  scalp,  20 
temporal,  24 
of  thigh,  509 

transversalis,  276-277,  292 
Fasciculated  bladder,  421 
Fauces,  isthmus  of,  122 

pillars  of,  122 
Fecal  concretions,  346,  351 

impaction,  346 
Felon,  222 

Femoral  aneurysm,  493 
arch,  276,  302,  304 
artery,  490,  493,  501,  509,  510 
compression  of,  493,  509 
ligation  of,  493-494,  509 
line  of,  490 
canal,  302,  305-306,  492 
hernia,  301,  305-300,492 
ring,  302-305,  490 
sheath,  276,  302 

veins,  302,  490,  493-194,  509,  510 
ligature  of,  493-494 
wound  of,  40 1 
Femur,  condyles  of,  512,  517,  518,  521 
dislocal  ion  of,  107,  500 
epiphyses  of,  498,  499,  506,  512,  .r,i7, 

524  625 
excision  of,  524 
$12 
fracture  of,  510,  525 
head  of,  486,  180,  405,  500,  501,  502 


584 


INDEX 


Femur,  neck  of,  angle  of,  503 
fracture  of,  503,  504 

at  base  of,  503 
osteoporosis  of,  503 

trochlear  surface  of,  511,  519,  521 
Fenestra  ovalis,  59 

rotunda,  59 
Fibula,  526 

fractures  of,  530,  537-539 

head  of,  512,  526 
Fifth  nerve,  78,  93 

section  of.     See  Branches. 
Fimbria  ovarica,  440,  442 
Finger,  cutaneous  nerve  supply  of,  220, 
222 

dislocation  of,  224 
Fibrous  sheaths  of  flexor  tendons  of  fin- 
gers, 219 
Fissure  of  anus,  416 

of  Rolando,  43,  46-48 

of  Sylvius,  48-50 

parietoocciptal,  50 
Fissures  of  brain,  localization  of,  46 

of  Santorini,  54 
Fistula,  branchial,  162 

in  ano,  416,  483,  484 

lacrymal,  71 

salivary,  99 

umbilical,  290 

vesicovaginal,  424,  447 
Flat  foot,  543,  545,  546 
Flechsig's  association  centres,  46 
Fleishmann's  bursa,  120 
Flexor  carpi  radialis,  209-210 

ulnaris,  210 
Fold  of  buttock,  485 

of  elbow,  194 
Fontanelles,  26 
Foot,  539 

abscess  of,  543 

amputations  of,  549-550 

arches  of,  543,  544 

longitudinal,  544,  545 

maintained  by,  545 
transverse,  545 

maintained  by,  545 

bloodvessels  of,  540,  542 

bursse  of,  543-544 

dislocations  of,  536,  548-549 

fasciae  of,  542 

fractures  of,  551 

joints  of,  547 

lymphatics  of,  544 

nerves  of,  543 

surface  markings  of,  539 

synovial  membranes  of,  549 

topography  of,  540 

veins  of,  542 
Foramen  cecum  (of  tongue),  116,  152 

of  Majendie,  41,  564 

of  Winslow,  321,  323,  335,  370,  390 
Forearm,  204 

amputation  of,  208 

bones  of,  206 

dislocations  of,  199-201 

fractures  of,  206 


Forearm,  landmarks  of,  204-205 

surface  markings  of,  204-205 

vessels  of,  205 
Foreign  body  in  air  passages,  146-147, 
152,  251 
in  ear,  54,  55 
in  esophagus,  263 
Fossa,  duodenojejunal,  337 

ileocecal,  353 

ileocolic,  353 

infraclavicular,  164 

inguinal,  293 

intersigmoid,  357 

ischiorectal,  411,  481,  483 

nasal,  82,  83 

navicularis,  455 

ovarica,  439 

retrocolic,  353 

of  Rosenmuller,  65,  126,  128,  162 

supraclavicular,  132 
Fourchette,  452 
Fourth  nerve,  77 

paralysis  of,  77 
Fracture.     See  Several  bones. 

dislocation  of  vertebras,  561-563,  566 
Frenum  lingua;,  115 

preputii,  464 
Frontal  artery,  21 

convolutions,  50 

sinuses,  66,  85,  87 
empyema  of,  89 
fracture  of,  88 
operations  on,  89 
Fundus  of  stomach,  323,  325 
Funicular  artery,  438,  446 

process,  hernia  into,  296 


G 


Gaertner,  duct  of,  441 
Gall-bladder,  366 

empyema  of,  368 

lymphatics  of,  369 

operations  on,  285-286,  369 

position  of,  366 

relations  of,  366,  368 
Gallstones,  368 
Ganglion,  212 

Gasserian,  39-40,  78,  97 
removal  of,  40 
Gastrectasia,  325-326 
Gastrectomy,  329 
Gastric  ulcer,  330,  332 
Gastrocnemius,  513,  526,  528 
Gastrocolic  ligament,  320,  335,  356,  373 
Gastro-enter ostomy,  328-329 
Gastroptosis,  326 
Gastrosplenic  omentum,  377 
Gastrostomy,  327-328 
Gastrotomy,  327 
Genital  organs,  female,  431,  451 

male,  425,  452 
Genitocrural  furrows,  394 

nerve,  298,  467,  474,  494 
Genu  valgum,  517,  518 


INDEX 


585 


Gimbernat's  ligament,  274,   302-304 

Glabella,  25 

Glans  penis,  464 

Glaucoma,  cervical  sympathetic  in,  143 

Glenoid  cavity,  104.'  17(3-180 

Glisson's  capsule,  304 

Glossitis,  114 

Glossopharyngeal  nerve,  118 

Glottis,  146 

edema  of,  147-148 

spasm  of,  147 
Gluteal  abscess,  487 

aneurysm,  488 

artery,  404,  486,  488 

ligature  anil  wounds  of,  486,  488 
3cia,  1^7 

fold,  394,  485 

muscles,  47.5,  485-488 
paralysis  of,  488 

nerves,  486-487 

region,  485 
Gluteus  maximus,  475,  485,  488 

medius,  485-488 
Goitre,  152.  155 
Graafian  follicles,  411 
Great  auricular  nerve,  55,  102,  132 
Groin,  fold  of,  268,  269 
Gubernaculum  testis,  468,  469 
Gullet.     See  Esophagus. 
Gums,  112 

in  lead  poisoning,  113 

in  mercurial  poisoning,  113 

in  scurvy,  113 
Gustatory  nerve,  119 

operations  on,  119 


II  alltw  valgus,  543 
Bammer  toe,  551 
Hamstring  muscles,  510,  515 
tendons,  conl  racture  of,  515 
rupture  of,  515 
Hamular  process,  120,  121 
Band,  215 

cutaneous  Derve  supply  of,  220 
oBor  tendons  of,  222 
iae  of,  218 
landmarks  of,  215 
motor  nerve  supply  of,  222 
surface  markings  of,  215 
-  i:il  sheal li-  of,  219 

U  Of,  220 

Hard  palate,  L20 
Harelip,  1 1 1 

operal  ion  on,  1 12 
Head,  17 

17 
■  al  consideration  .  1 7 
iral  |>o-ii ion  of,  1 7 

apex  of,  25 1 

:  i  r  t «  i 

placemenl  -  of,  255 
operation   on, 


Heart,  orifices  of,  254 

physical  examination  of,  253 

position  of,  253 

relation  to  surface,  254 

surfaces  of,  253 

topography  of,  254 

wounds  of,  256 
Hematocele,  407,  441,  445,  448,  452 
Hematomata  of  scalp,  23 

of  ear,  52 
Hematomyelia,  566,  575,  576 
Hemianopsia,  76 

Hemorrhage  in  amputation  at  hip  joint, 
507 
at  shoulder-joint,  184 

from  frenum  lingtue,  116 

from  intercostal  vessels,  232 

from  internal  mammary,  233 

in  lithotomy,  479,  480 

meningeal,  34 

from  operations  on  tongue,  116,  117 

from  tonsil,  124,  125 

in  tracheotom3r,  152 
Hemorrhoidal  artery,  inferior,  483 
superior,  413 

veins,  413,  414 
Hemorrhoids,  414 
Hemothorax,  245 
Hepatic  abscess,  356,  362,  363 

artery,  321,  364 

colic,  372 

duct,  370 

flexure,  356 
Hepatocolic  ligament,  357 
Hepatoduodenal  ligament,  321,  334,  336 
Hermaphroditism,  465,  468 
Hernia,  acquired,  external  inguinal,  296 

adiposa,  306 

congenital  inguinal,  295 

diaphragmatic,  239 

direct  inguinal,  296 

encysted,  296 

external  inguinal,  294 

femoral,  305 

indirect  inguinal,  294 

Infantile  inguinal,  296 

inguinal,  293  300,  451 

in  female,  300,  -1 16,  151 

internal  Inguinal,  296 

Interparietal,  300 

into  funicular  process,  2(.I6 

Ischiatic,  W)5 

ischiorectal,  105 

lumbar,  313 

mesenteric,  322 

oblique  inguinal,  2!)  I 

obturator,  Mil,  405 

omental,  320 

operations,  207 

under  local  anesthesia,  298 

perineal,  105 

pro-peritoneal,  278 

pudendal,  105,  151 

lit roperitoneal,  3:'>7 

sigmoid,  :'>57 

umbilical,  288  289 


586 


INDEX 


Hernia,  vaginal,  405 
Herniotomy,  297-298,  306 
Herpes  zoster,  280-281 
Hesselbach's  triangle,  293 
Hey's  amputation,  550 
Hiatus  diaphragmaticus,  239,  381 
Hip,  dislocations  of,  497,  500 

dorsal  forms  of,  500,  501 
forward  forms  of,  500,  501 
pathological,  499 
reduction  of,  502 
rupture  of  capsule  in,  496 
fractures  about,  503-506 
joint,  494 

amputation  at,  507-508 

control  of  hemorrhage  in, 

507 
incisions  for,  507-508 
vessels  divided  in,  507-508 
capsule  of,  495,  504 
congenital  dislocation    of,  503, 

557 
disease  of,  485,  497-499,  557 

reflex  pain  in,  499,  500 
effusion  into,  496 
excision  of,  506 
movements  of,  497 
strongest  part  of,  495 
tension  of,  498 
weakest  part  of,  495 
region  of,  485 
topography  of,  494 
Housemaid's  knee,  514 
Houston's  folds  of  rectum,  411,  412 
Humerus,  164,  190 

bicipital  groove  of,  164 
condyles  of,  194-195 
dislocations  of,  177 
epiphyses,  separation  of,  183,  203 
fracture  of  anatomical  neck  of,  181- 
182 
of  surgical  neck  of,   181,  183- 
184 
fractures  of,  182-184,  193,  201-203 

non-union  after,  193 
head  of,  164 

great  tuberosity  of,  164,  177,  178- 
179 
Hunter's  canal,  509 
Hydatid  of  Morgagni,  441,  472 
Hydrencephalocele,  27 
Hydrocele  in  female,  446,  451 
of  cord,  295,  470 
of  tunica  vaginalis,  467,  468,  470 
Hydrocephalus,  26 
Hydronephrosis,  389 
Hydrosalpinx,  442,  443 
Hymen,  449 
Hyoid  bone,  129,  144 
fractures  of,  144 
Hypertroplry  of  the  prostate,  425^127 
Hypochondriac  region,  287 
Hypogastric    artery    (obliterated),    293, 
418,  420 
region,  287 
Hypoglossal  nerve,  118,  138,  141 


Hypospadias,  465 
Hypothenar  eminence,  215 
Hysterectomy,  438 


Ichthyosis  of  tongue,  116 
Ileocecal  intussusception,  347 
region,  344 
tumor,  346 
valve,  346 

competency  of,  347 
Ileocolic  artery,  352 

intussusception,  347 
Ileum,  338 

limits  of,  339 
position  of,  338 
Iliac  abscess,  301,  307,  312 
artery,  common,  308 

ligature  of,  310 
external,  308,  309 
ligature  of,  309 
line  of,  308 
relations  of,  309 
crest,  268 

fascia,  276,  301-302,  310 
furrow,  268 
regions,  287,  307 
spine,  anterior  superior,  268,  402 
inferior,  494 
posterior  superior,  268,  485,  486 
Iliocostal  space,  312,  558 
Iliofemoral  band,  495,  497,  500,  501,  502 
Iliohypogastric  nerve,  280,  298 
Ilio-inguinal  nerve,  280,  298 
Iliopectineal  line,  274,  397 
Iliopsoas  bursa,  492,  495-496 

muscle,  311,  492,  507 
Iliotibial  band,  486-487,  508,  513 
Ilium,  312 

Imperforate  anus,  416 
Incontinence  of  feces,  573 

of  urine,  422-423,  573-574 
Indirect  inguinal  hernia,  294 
Inequality  of  limbs  in  length,  511 
Infantile  inguinal  hernia,  296 
Inferior  carotid  triangle,  139 
dental  nerve,  97 

excision  of,  97 
maxilla.     See  Mandible, 
thyroid  veins,  150,  154 
Infraclavicular  fossa,  164 
Infra-orbital  foramen,  94,  96 
nerve,  73,  89,  94,  104 
excision  of,  94 
Infraspinatus,  179 

Infundibuliforrn  fascia,  277,  292,  466,  467 
Infundibulopelvic  ligament,  440,  445 
Infundibulum,  85,  89,  90 
Inguinal  canal,  290,  292 

nerves  about,  298 
colotomy,  358 
fold,  268,  269 
fossa?,  293 
hernise,  293-300 


INDEX 


587 


Inguinal  lymph  nodes,  490,  491 

region,  290 
Inguinofemoral  region,  301 
Inion,  25 
Innominate  artery,  259 

aneurysm  of,  259-200 
ligation  of,  259,  260 
bone,  399 

vein,  left,  150,  258-200 
right,  259 
Interarticular  fibrocartilage  of  jaw,  109 
Intercolumnar  fascia,  271,  291 
Intercostal  arteries,  134,  232 
nerves,  233 
spaces,  232 
[ntercostohumeral  nerve,  233 
Internal  abdominal  ring,  292 

carotid  artery,  39,102,128,142 

in  operations  on  tonsil,  124 
cutaneous  nerve,  191,  196 
jugular  vein,  140-141,  142,  161,  168 
mammary  artery.  233 
oblique  muscle,  271 
pudic  artery,  405,  479,  183,  486 
Saphenous  nerve,  493,  508,  509,  514, 
520,  527 
vein.    490-493,    508,    509,    514, 
520,  527-529,  533,  542 
Interosseous  arteries,  208 

membrane,  206 
Interparietal  bone,  27 

hernia.  300 
Interecapulothoracic  amputation,  173 
[ntersigmoid  Fossa,  357 
Intervertebral  disks,  559 
[ntestine,   large,   344,   353.     See  Colon, 
cecum,  and  rectum. 
resection  of,  343 

small,     334.     See    also    Duodenum, 
ileum,  and  jejunum. 
diverticula  of,  3  12 
identification  of  parts  of,  323, 

339,  340 
injury  of,  3 13 
length  of,  334 

mesentery  of,  322 
Lymphatics  of,  342 
operations  on,  3 13 
position  of,  338 
reseel  ion  of,  3 13 
rtructure  of,  339,  340,  341 

I  -  of,  •'■  12 
wall  of,  340,  341 
wounds  of,  340,  341,  343 
Intestinal  Buture,  343  344 

icoracoid  dislocation,  L78 
Intussusception,  3 13,  3 17 
Inversion  ol  testis,  168 
Ischemic  paralysis,  207,  208 
I-ehiatie  hernia,  105 
ofemoral  band,  197 
iliopubic  rami,  394 
Ischiorectal  ab 

111,  IM.  183 
anterioi  183 

apex  oi,  183 


Ischiorectal  fossa,  boundaries  of,  483 
posterior  recess  of,  483 
hernia,  405 
Ischium,  spine  of,  486 
Isthmus  of  fauces,  122 

of  thyroid,  149-150,  152,  153 
division  of,  150,  152,  153 


Jaw.     See  Mandible  and  superior  max- 
illa. 
Jejunum,  338 
limits  of,  339 
position  of,  338 
Jejunostomy,  343 
Joints.     See  Special  articulation. 
Jugular  vein,  anterior,  130,  140,  144,  155 
external,  103,  133,  168 
internal,  140-141,  142,  161,  168 


Keloid,  frequent  seat  of,  91,  229 
Kidney,  abnormalities  of,  384,  385 

abscess  about,  315,  381,  382,  384 

exposure  of,  381,  383,  387 

fatty  capsule  of,  383 

fibrous  capsule  of,  387 

fixation  of,  383,  384 

floating,  383,  384 

hilum  of,  380,  385 
incision  of,  387 

horseshoe,  385 

movable,  384 

nerve  supply  of,  386,  387 

operations  on,  387 

pelvis  of,  385 

perirenal  fascia  of,  383 

position  of,  379,  380 

relations  of,  242,  244,  335,  355,  381- 
383 
to  peritoneum,  383 

rupture  of,  383 

tumors  of,  382 

I  unica  adiposa  of,  383 

vessels  of,  -is"> 
trounds  of,  383 
Knee,  bursa  about,  51  I.  516 
coverings  of,  51  1  515 
fascia  of,  514,  515 
fractures  about,  519,  525 
joint,  517 

amputations  through,  524,  525 

arthrectomy  of,  524 

dislocations  of,  515,  516,  517 

drainage  of,  52 1 

effusion  into,  612,  513,  519,522 

523 

.  iaion  of.  52 1 
interarl  icular  line  of,  513 
Ligaments  of,  518 
Loo  '■  bodies  in,  523 
ubcrural  bursa  of,  522 


588 


INDEX 


Knee  joint,  synovial  membrane  of,  522, 
523 
synovitis  of,  523 
region  of,  511 
surface  markings  of,  511 
Knock-knee,  517,  518 
Kocher's  "normal  incision"  for  upper  cer- 
vical triangle,  130,  138,  141 
Kraske's  operation,  417,  489 
Kyphosis,  556 


Labia  majora,  451 

minora,  451 
Lacrymal  abscess,  71 

apparatus,  70 

gland,  70,  73 

groove,  71 

sac,  68,  71 

tumor,  71 
Lacuna  magna,  urethral,  456 
Lacunae  of  Morgagni,  456 
Lambda,  26 
Lambdoid  suture,  26 
Laminectomy,  563 
Large  intestine.     See  Cecum,  colon,  and 

rectum. 
Laryngeal  nerve,  superior,  118,  139,  144, 
147,  148-149 
inferior,  147,  148-149,  151,  153- 
154,  258-259 
Laryngismus  stridulus,  147 
Laryngoscopic  image,  146 
Laryngotomy,  149 
Larynx,  145 

excision  of,  148 

foreign  bodies  in,  146-147 

fracture  of,  148 

mucosa  of,  147 

polypi  of,  148 

superior  aperture  of,  146 

surface  markings  of,  129,  145-146 

topography  of,  145-146 
Lateral  curvature  of  spine,  227,  558 

ligaments  of  uterus,  432,  436,  444. 
See  Broad  ligaments. 

lithotomy,  479 

sinuses,  course  of,  38 

ventricles  of  brain,  50,  51 
Latissimus  dorsi,  186,  188,  313 
Left  auricle,  253-254 

ventricle,  253,  254,  256 
Leg,  525 

amputation  of,  530,  531 

bones  of,  529 

fascise  of,  527 

deep  transverse,  527,  528,  533 

fractures  of,  525,  530,  537-539 

skin  of,  527 

surface  landmarks  of,  525-526 

topography  of,  526 

vessels  of,  526-528 
Lembert  sutures,  303 
Levator  ani,  404,  405,  408,  411,  427,  479, 
483 


Levator  ani,  relation  to  fistula  in  ano, 
416 

palati,  92,  120,  121 

palpebrse,  68,  74,  77,  78 
Lienophrenic  ligament,  376 
Lienorenal  ligament,  376 
Ligament.     See  Special  joints,  etc. 
Ligamentum  denticulatum,  564 

patellse,  512,  519,  521 
drainage  of,  524 

subflavum,  560,  564 

teres,  495,  497,  507 
Lighterman's  bottom,  488 
Line,  axillary,  229 

mammary,  229 

scapular,  229 

sternal,  228 

white,  405,  411,  483 
Linea  alba,  268,  275,  283 
hernia  of,  275 
incision  in,  283 

semilunaris,  268,  274,  283 
incision  in,  283 
Linese  transversse,  269,  272 
Lingual  artery,  117,  138 

nerve,  119 

tonsil,  116 

triangle,  138 
Lipomata  in  deltoid  region,  174 

in  region  of  Scarpa's  triangle,  491 

on  buttock,  487 
Lips,  109 

development  of,  111 

layers  of,  109-110 

lymphatics  of,  110 
Lisfranc's  amputation,  550 
Lithotomy  in  children,  480 

lateral,  479 

to  be  avoided  in,  479-480 
parts  divided  in,  479 

median,  480 

versus  lateral,  481 

suprapubic,  408,  419 
Littre's  operation,  358 
Liver,  359 

abscess  of,  363 

accessible  to  operation,  361 

carcinoma  of,  366 

cirrhosis  of,  364 

cysts  of,  363 

dulness,  360 

enlargements  of,  361 

fixation  of,  362 

general  considerations  of,  359 

limits  of,  360 

malposition  of,  362 

nerves  of,  364-366 

position  of,  359,  360,  361 

reflex  pain  in  disease  of,  393 

relations  of,  362 

ruptures  of,  359,  363 

structure  of,  363,  364 

surfaces  of,  362,  363 

wounds  of,  360,  362 
Localization,  cerebral,  42-46 
Lockjaw,  109 


INDEX 


589 


Longitudinal  bands  of  large  intestine,  344, 
354 

sinus,  superior,  36 
Lordosis,  399.  498,  557 

in  hip  disease,  313,  557 
Lower  limb,  length  of,  511 

cutaneous  nerve  supply  of,  551 
measurement  of,  402,  403 
motor  nerve  supply  of,  552 
Ludwig's  angina,  120 
Lumbar  abscess,  314 

colotomy,  354-355,  358 

fascia,  314 

hernia,  313 

incisions,  315 

lvmph  nodes,  392 

nerves,  279-280,  316 

puncture.  41,  313,  560,  565 

region,  287,  312 
wounds  of,  316 

spine,  556,  557-560 

vertebra-,  spines  of,  267,     312,     314, 
394,  55  I 

vessels,  316 
Lung,  215 

apex  of,  168,  245,  247 

auscultation  of,  248,  249 

base  of,  246 

at  birth,  247 

borders  of,  245 

capacity  of,  248 

cardiac  incisure  of,  245,  253 

elasticity  of,  249 

fissures  of,  246 

hernia  of,  134,  249 

lobes  of,  246-247 

in  neck,  134 

<<ut line  of,  245 

position  of,  2  15 

puncture  of,  247 

relations  of,  246 

rod  of,  247,  249,  258 

vessels  of,  248 

wounds  of,  168,  249 
Luschka's  tonsil,  65,  128 
Lymph  nodes.    See  Each  region. 
-sels.    See  Each  region. 


M 


M<  I'.'  bnby'b  point.  268,  350 

tomy,  518 
Macroglossia,  1  is 
boma,  l  lii 

lie,  foramen  of,  1 1 ,  ■">•!  I 
Malignant  pusl ule,  91 
Malleoli,  .",:'.!   539,  548 

bad  ..   .".:;'.».  .".is 

Malleu     proct  li  ear 

drum,  56,  57 

Mamma.      8a     Bl 

Mammary  line,  229 
Mandible,  106 

condyle  of,  106  101 

dislocation  of,  108 


Mandible,  excision  of,  106-107 
fracture  of,  106 
necrosis  of,  103-104,  112 
spine  of,  97 
tumors  of,  106-107 
Margo  acutus,  253-254 
Masseter,  78,  107-108 
Mastoid  antrum,  60 

development  of,  63 
inflammation  of,  63 
operation  on,  61 
passageway  into,  60 
position  of,  60 
relations  of,  55,  61 

to  sigmoid  sinus,  61 
cells,  63 
nodes,  160 
region,  25 
vein,  38 
Maxilla,  attachments  of,  104 
cleft  of,  122-123 
excision  of,  104-105 
fracture  of,  104 
necrosis  of,  103 
temporary  resection  of,  105 
tumors  of,  104,  105,  114 
Maxillary  sinus,  85,  89 

empyema  of,  89 
mucosa  of,  90 
orifice  of,  90 
relations  of,  89,  90 
tumors  of,  90 
Measurement  of  lower  limb,  402,  403 

of  upper  limb,  163,  179-180 
Meatus,  external  auditory,  53 

internal  urinary,  418,  423,  452,  458 
Meatuses  of  nose,  84,  85 
Meckel's  diverticulum,  288,  342 
ganglion,  89,  0  1 

excision  of,  85,  94-95 
Median  lithotomy,  480 

nerve,  190,  191,  192,  199,  209,  220, 
222 
paralysis  of,  222 
vein,  196 

basilic,  196 
cephalic,  196 
Mediae!  inum,  abscess  of,  230 
Mediotarsal  joint,  539, 540, 549 

amputation  at,  550 
Medulla,  16 
Meibomian  glands,  69 
Membrana  flaccida,  56 
i  \  mpani,  56  58,  I'd 

examinal  ion  of,  in  adull  s,  53,  ;~>  I 

in  infant 
otoscopic  image  of,  56,  •">? 
paracentesii  of,  57 
rupture  of,  32 
umbo  of,  56 

occluding,  161 
Membranes  of  brain,  33 

of  spinal  cord,  486,  563,  560 
Membranous  urel  bra,  HO,  15 1 
Meningeal  arterj ,  middle,  3  I 

hemorrhage  from,  '■'< I ,  '■'<  I 


590 


INDEX 


Meningeal  artery,  middle,  operations  on, 
35 
position  and  course  of,  35 
Meninges  of  brain,  33 

of  spinal  cord,  486,  563,  564 
Meningitis  from  otitis  media,  etc.,  60 
spinal,  from  carbuncle,  bed-sores,  etc., 
564 
Meningocele,  27,  81 

spinal,  559 
Meningomyelocele,  559 
Mental  foramen,  96 
nerve,  96 

or   association    centres    of    cortex, 
46 
Mesenteric  arteries,  391-392,  407 
hernia,  322 
plexuses,  392-393 
Mesenteriolum,  349 
Mesentery,  321 

holes  in,  322,  339 
length  of,  299,  322 

in  relation  to  hernia,  299,  322 
suspensory  muscle  of,  322,  337 
Mesocolon,  transverse,  317,  323,  335,  336, 

355-357 
Mesogastrium,  320 
Mesosalpinx,  442,  445 
Metacarpal  bones,  fracture  of,  224 
Metacarpophalangeal  joint  of  thumb,  dis- 
location at,  224 
Metatarsal  bone,  fifth,  539 

fractures  of,  551 
Metatarsophalangeal  joint,  540 
amputation  at,  550 
dislocation  at,  551 
Metatarsalgia  (Morton's),  550 
Microcephalus,  18,  27 
Middle  meningeal  artery.    See  Meningeal. 
Miner's  elbow,  197 
Mitral    orifice,    projection    of,    on    chest 

wall,  254 
Mons  veneris,  270,  394 
Morgagni,  columns,  valves,  and  sinuses  of, 
413 
lacunae  of,  456 
hydatids  of,  441,  472 
Morton's  metatarsalgia,  550 
Motor  centres  of  cortex,  42-43 
oculi,  68,  77 
paralysis    in  injuries  to  cord,  569- 

574 
nerve    roots,     trophic     centres    of, 
567 
Mouth,  diaphragm  of,  114 

floor  of,  114,  119 
Mucous  polvpi  of  nose,  86 
Mumps,  101-103 
Muscle  of  Horner,  70 
Muscular  compartment,  302 
Musculocutaneous  nerve,  191,  542 

of  leg,  527 
Musculospiral  nerve,  190,  192,  195 

paralysis  of,  192 
Mylohyoid  muscle,  114 
Myxedema,  154 


N 


Nares,  anterior,  82 

plugging  of,  82,  86 

posterior,  82 
Nasal  bones,  fracture  of,  80 

cartilages,  81 

douche,  87 

duct,  71,  72,  85 

fossae,  82,  83 

lymphatics  of,  86 
mucosa  of,  84-86 
nerve  supply  of,  87 

orifice,  anterior,  82 

polypi,  84,  86 

septum,  80,  83,  84 
deviation  of,  83 
Nasion,  25,  46 
Nasopharyngeal  adenoids,  128 

polypi,  128-129 
Nasopharynx,  128 
Nates,  fold  of,  394,  485 
Neck,  129 

abscess  of,  158-159 

deep  fascia  of,  156-159 

embryology  of,  161 

fistulae  of,  162 

landmarks  of,  129 

lung  and  pleura  in,  241,  245 

lymph  nodes  of,  159-161 

surface  markings  of,  129 

triangles  of,  132-139 

vessels  of,  133,  134,  138-142 

wounds  of,  144-145 
Nelaton's  line,  394,  486,  494,  501 
Nephrectomy,  387 
Nephrolithotomy,  387 
Nephrorrhaphy,  387 
Nephrotomy,  387 
Nerve  supply  of  lower  limb,  552 
of  upper  limb,  220,  222 
Nerves.     See  Various  regions. 

division  of.     See  Various  regions. 

exit  of,  from  spinal  cord,  568,  571, 
575 
Neuralgia,  trigeminal,  94,  96-97 
Nipple,  236 

affections  of,  236 

line,  229 

position  of,  229,  236 
Nipples,    supernumerary,    238-239,   490, 

491 
Nose,  atrium  of,  85 

bleed,  86 

blood  supply  of,  86 

cartilaginous  part  of,  81 

columna  of,  82 

coverings  of,  80 

external,  79-S2 

foreign  bodies  in,  87 

operations  on,  81 

"saddle,"  81 

vestibule  of,  82 
Notch  of  Rivini,  56 
Nuck,  canal  of,  446,  451 
Nymphae,  451 


INDEX 


591 


Oblique  inguinal  hernia,  294 

muscles  of  abdomen,  269,  271 
aponeuroses  of,  273 
of  orbit,  74,  75 
Obturator  artery,  304 
canal,  404 
fascia,  405,  479,  483 
foramen,  404,  501 
hernia,  404 
nerve,  404,  405 

paralysis  of,  552 
or  thyroid  dislocation  of  hip,  500-501 
Occipital  artery,  21,  139 
lymph  nodes,  22 
protuberance,  external,  25,  130 
sinus,  38 
triangle,  132 
Occipitofrontalis,  20,  22,  65,  93 

aponeurosis  of,  19,  20,  22,  34 
Odontomata,  114 
Olecranon,  194-195 

fractures  of,  204 
Olfactory  nerve,  85 
Omental  grafts,  321 
adhesions,  320,  321 
sac,  lesser,  323,  330,  373 
Omentum,  great,  320 
in  hernia,  320 
small,  321,  373 
torsion  of,  321 
Omohvoid,  132,  139,  140 
( tphthalmic  veins,  39,  61,  78-79,  86,  91 
Optic  nerve,  76 

and  subarachnoid  space,  41,  76- 
77 
Orbicularis  oris,  93,  110 

palpebrarum,  65,  66,  93 
nerve  supply  of,  66 
Orbit,  72 

abscess  of,  79 

action  of  muscles  of,  73 

aponeurosis  of,  73-74 

axis  of,  72 

detection  of  paralysis  of  muscles  of, 

76 
dimensions  of,  72,  7'A 
foreign  bodies  in,  7'.t 
fracture*  oi   72 
margin  <>!',  73 
muscles  of,  7 1,  ~~> 
nerves  of,  7H-78 

pararj  rii  of,  77  78 
pulsating  tumors  of,  78 
relal  ions  of,  72,  7'.', 
region  of,  05 
■  l-  nt,  78 
Orchitis,  170 

■ !-.  frad  nn--  ni .  551 
binominal  um.  '■'•'*'■> 
magnum,  position  ol .  209 
0    I  ill 
< >titia  medi 
138 
•  -  <if,  I  i  l 


Ovary,  development  of,  441 
fossa  of,  439 
in  hernia,  440 
palpation  of,  409,  440 
pedicle  of,  440,  445 
position  of,  439,  440 
prolapse  of,  440 
relations  of,  409,  440 
structure  of,  440,  441 
tumors  of,  141 
vessels  of,  440,  445 

Oviduct,  442 


Pacchionian  bodies,  29,  41 
Pachymeningitis  interna,  36 
Palate,  120 

aponeurosis,  121 

blood  supply  of,  120,  122 

cleft,  122-123 

operations  on,  120,  121,  123-124 

formation  of,  122 

hard,  120 

muscles  of,  121 

paralysis  of,  121 

soft,  121 
Palatine  artery,  posterior,  120,  122 
Palm,  215 

abscess  of,  218 

creases  of,  215 

cutaneous  nerve  supply  of,  220 

motor  nerve  supply  of,  222 

skin  of,  217 

synovial  sheaths  of,  219 
Palmar  arch,  deep,  220 
superficial,  220 

fascia,  218 
Pal  maris  longus  tendon,  209,  214 
Palpebral  conjunctiva,  68 

fascia,  67 

folds,  66 

ligaments,  68 
Pampiniform  plexus,  474 
Pancreas,  373 

cysts  of,  :;7i 

diseases  of.  ">7  I,  375 

duel  of,  371,  374 

operal  ions  on,  :\7'-'< 

position  of.  373 

relations  of,  334  335,  :>>7A 
Pancreal  i'is,  :!7.~i 
Papilla  of  duodenum,  336,  '■'>>  I 

of  eyelid,  69,  70 
Paracentesis  of  abdomen,  319 

oi  pericardium,  '-'  12,  252 

of  thorax,  232 

of  tympanum,  ■">< 
Paraceni  ral  lobule,   13 
Paradidymis,   \7'2 
Paralysis  in  spinal  injuries,  569  570,  573 

.-,7  1 

interior  crural  nerve,  552 
of  cervical    j  mpal  hel  ic,  78,  I  I  3 
of  external  popliteal  nerve.  r,r,-j, 


592 


INDEX 


Paralysis  of  facial  nerve,  92-93 

of  fourth  cranial  nerve,  77 

of  great  sciatic  nerve,  552-553 

of  internal  popliteal  nerve,  552 

of  median  nerve,  222 

of  musculospiral  nerve,  192 

of  obturator  nerve,  552 

of  sixth  cranial  nerve,  77 

of  third  cranial  nerve,  77 

of  ulnar  nerve,  222 
Paraphimosis,  462 
Parathyroid  glands,  155 

arteries  of,  155-156 
Parietal  eminence,  25,  50 

fissure,  28 

foramen,  26 

lobe,  44 

and  visceral  anastomoses  of  abdo- 
men, 279,  391-392 
Parieto-occipital  fissure,  50 
Parotid  abscess,  101,  102,  103 

compartment,  99 

gland,  101 

relations  of,  55,  101 
structures  in,  102 
nerve  supply  of,  102 
removal  of,  103 

lymph  nodes,  22,  103,  160 

region,  99 

sheath,  100-101 

tumors,  103 
Parovarium,  441 
Parumbilical  vein,  279,  392 
Patella,  511 

dislocation  of,  521 

floating  of,  523 

fractures  of,  514,  519-521 
Patellar  click,  523 

ligament,  512,  519,  521 
lateral,  514,  519-522 
rupture  of,  521 
Pectineal  compartment,  302 

fascia,  302 
Pectineus,  302 
Pectoral  fascia,  185 

Pectoralis  major,  165,  171,  185,  188,  190, 
234 

minor,  165,  171,  185-186,  188 
Pedicle,  ovarian,  440,  445 
Pelvic  arches,  397 

cellulitis,  308,  407,  444 

counter  arches,  397 

deformities,  398 

diaphragm,  404 

fascia,  405 

hematocele,  407,  441,  445,  448 

herniae,  404,  405 

peritonitis,  407 

symphysis,  394,  397 

viscera,  407 
Pelvis,  axis  of,  317,  400 

diameters  of,  401 

in  female,  401 

floor  of,  404 

fractures  of,  398-399 

landmarks  of,  394 


Pelvis,  mechanism  of,  397 

movements  of,  401 

nerves  of,  406 

obliquity  of,  399 

outlet  of,  395,  404 

planes  of,  399-401 

vessels  of,  406 
Penetrating  wounds  of  abdomen,  282,  317 
Penis,  461 

angle  of,  464 

dartos  of,  462 

dorsal  vein  of,  406,  459,  463,  479 

erection  of,  463,  478,  574 

fascia  of,  463 

layers  of,  461-463 

lymphatics  of,  465 

malformations  of,  465 

skin  of,  461 

suspensory  ligament  of,  463-464 
Perforating  ulcer,  542 
Pericardium,  251 

effusions  in,  252 

elasticity  of,  252 

tapping  of,  242,  252 
Pericranium,  20 
Perineal  body,  411,  482 

fascia,  476 

hernia,  405 

incisions,  475,  479-481 

interspaces,  476-478 

ledge,  476-477,  483 
Perinephritic  abscess,  315,  318,  382,  384 
Perineum,  411,  474 

boundaries  of,  474-475 

central  point  of,  475,  481 

depth  of,  475 

divisions  of,  475 

fascia?  of,  476,  477,  479 

female,  481 

landmarks  of,  475 

layers  of,  476-479 

median  raphe  of,  475 

muscles  of,  477-478 

"proper,"  475-483 

rupture  of,  410,  482 
Peritoneal  absorption,  319 

adhesions,  318 

cavity,  317 

sac,  lesser,  323,  330,  373 

transudation,  319 
Peritoneum,  elasticity  of,  317 

infection  of,  318 

parietal,  307 

visceral,  320 
Peritonitis,  317,  318,  319 
Perityphlitic  abscess,  308 
Peroneal  artery,  526,  528,  541 

muscles,  546 

tendons,  532,  533,  539 
contracture  of,  534 
displacement  of,  533,  547 

tubercle,  539 
Pes  cavus,  543,  545,  546 
Petit's  triangle,  271,  313 
Petrosal  nerve,  great  superficial,  92 

sinuses,  39 


INDEX 


593 


Petrosquamous  suture,  60 

Peyer's  patches,  341 

Phantom  tumor,  273 

Pharyngeal  artery,  ascending,  124-125 

tonsil,  65,  128 
Pharyngomaxillary  space,  124 
Pharyngotomy,  subhyoid,  12S,  144 
Pharynx,  126 

divisions  of,  128-129 

foreign  bodies  in,  126 

lymphatics  of,  129 

relations  of.  126-128 
Phimosis,  456,  461 
Phosphorus  necrosis,  103 
Phrenic  nerve,  133,    174,   241,   258,    260, 

366,  392.  574 
Phrenocolic  ligament,  357,  376-377 
Pia  mater,  41 
Pigeon  breast,  227,  249 
Piles,  414 
Pinna,  52 

Pirogoff's  amputation,  550 
Plantar  arch,  wound  of,  540,  541 

arteries,  533,  540,  550 

fascia,  533,  542-543,  546,  547 
tenotomy  of,  543 

ligaments,  545-546 

nerves,  543 
Plantaris  tendon,  rupture  of,  528 
Platysma  myoides,  135-136 
Pleura,  241  ' 

borders  of,  241-242 

dome  of,  134,  241 

limits  of,  241-242 

in  lumbar  incisions,  242,  315,  381 

wounds  of,  244-245 
Pleural  adhesions,  244,  247 
Pleurisy,  244 
Plica  semilunaris,  275 
Pneumatocele,  63 
Pneumogastric  nerve,  140,  143,  144,  250, 

259,  392 
Pneumonia,  247-248 
Pneumothorax,  244-245 
Pollitzer's  method  of  inflating  the  middle 
ear,  64,  128 

pi  of  nose,  86 
Pomurn  Adami,  129,  145 
Pons,  Hi 
Popliteal  abscess,  515 

aneurysm,  515 

artery,  613,  515,  524,  529, 

bursee,  516,  517 

fascia,  515 

nerv-.  e  eternal,  513,  515 
paralysis  of,  562 
internal,  513,  516 
pari  552 

nodes,  513  516,  51  < 
don,  513 
513  516 
Portal    "in,  321,  364,  366 

tomotic  circulation  of,  •''»<>") 
i  notion  oi ,  365 
■  r  auricula  21,  '<2,  102 

condj  la  ■ 


Posterior  scapular  artery,  173 

tibial  artery,  526,  528,  531,  532,  540 
Postprostatic  pouch,  424 
Pott's  disease,  281,  556 

fracture,  537-538 
Poupart's   ligament,    273-274,    290-292, 

301-309 
Premaxillary  bone,  111,  122,  123 
Prepatella  bursa,  514 

bursitis,  514 
Prepubic  curve  of  urethra,  456,  459 
Prepuce,  461-462 
Priapism,  463,  574 
Processus  vaginalis,  291,   294-296,   46S, 

470,  473 
Profunda  arteries  of  arm,  190-191 

femoris,  490,  493 
Prolapsus  ani,  408,  411 

uteri,  434,  447-448 
Pronation,  206 
Pronator  quadratus,  207 

radii  teres,  205-207 
Prostate,  425 

abscess  of,  410,  427 

capsule  of,  406,  427 

enlargement  of,  410,  425,  427,  479 

lobes  of,  426 

operations  on,  428,  479,  481 

position  of,  427 

relations  of,  408,  409,  410,  427,  479 

size  and  shape  of,  425 

structure  of,  428 
Prostatectomy,  428 
Prostatic  plexus  of  veins,  427 

sinuses,  454 
Prostatoperitoneal  aponeurosis,  409 
Psoas  abscess,  301-302,  311,  556 

bursa,  492 

muscle,  492 
Pterion,  26 
Pterygium,  69 
Pterygoid  muscles,  107-108 
Ptosis,  68 
Pubic  crest,  268,  394 

spine,  268,  306,  486,  490 
Pubofemoral  band,  495-497 
Puboprostatic  ligaments,  406 
Pudendal  hernia,  405 
Pudic  artery,  internal,  405,  478 
accessory,  480 

nerve,  internal,  405,  478 
Pulmonary    artery,   248,    249,    257-258, 
260 

orifice,  254 

plexus,  250 

veins,  249 
Puncta  lacrymalia,  60,  70,  72 
Puncture  of  bladder,  410,  1 19 
Pupil,  77,  78 
Pylorectomv,  329 
Pyloroplasty,  329 
Pylorus,  324 

obstruction  of,  324,  :'»-'(»,  333 

operal  ions  on,  :;l".i 

DO   il  LOO  "I  .  ■';_'l)-327 

relation!  of,  326  -''.27 


594 


INDEX 


Pylorus,  stricture  of,  324,  332 

tumors  of,  333 
Pyosalpinx,  442,  443 
Pyramidalas  muscle,  273 
Pyriform  sinus,  146  \ 
Pyriformis,  404,  406 


Quadrattjs  femoris,  501 
lumborum,  315,  355 

Quadriceps,  512,  519,  521,  522 
expansion,  514,  521 
tendon,  519,  521 
rupture  of,  521 

Quinsy,  124 


R 


Radial  artery,  205,  208,  209,  211 

nerve,  205,  208,  214,  220 

pulse,  209 
Radiocarpal  joint,  209 
Radio-ulnar  joint,  212 
Radius,  205-206 

dislocation  of,  201 

by  elongation,  201 

fracture  of,  204,  206-207,  213-214 

head  of,  194,  199-200 

styloid  process,  of  208-209,  213 
Ranine  artery,  116-117 

vein,  116 
Ranula,  119 
Rectal  examination,  395,  409,  410 

hernia,  405 

polypi,  408 

tube,  358,  412 
Recti  muscles  of  orbit,  75 
Rectocele,  448 
Recto-urethralis  muscle,  481 
Recto-uterine  pouch,  434 
Rectovaginal  fistula,  447 

pouch,  409 

septum,  448 
Rectovesical  fascia,  406,  421,  479 

pouch,  409,  410,  418,  424,  425 
Rectum,  407 

anal  canal  of,  411 

attachments  of,  408 

development  of,  416 

divisions  of,  407 

examination  of,  409,  410 

excision  of,  408 

foreign  bodies  in,  408 

Houston's  folds  of,  411,  412 

introduction  of  hand  into,  408 

malformations  of,  417 

Morgagni's    columns,    valves,     and 
sinuses,  413 

newgrowths  of,  413 

nerve  supply  of,  414,  573 

operations  on,  417 

passage  of  bougie,  412 

pelvic  portion  of,  408 


Rectum,  prolapse  of,  408,  409,  411 

relations  of,  409,  426-427,  434,  479^ 
to  peritoneum,  409 

stricture  of,  413 

structure  of,  411 

"third  sphincter"  of,  413 

vessels  of,  413 
Rectus  abdominis  muscle,  272,    283-285 
sheath  of,  274,  283 

femoris,  507,  508 
Recurrent  laryngeal  nerve,  147-149,  151, 

153-154,  258-260 
Reduction  en  masse,  300 
Reflexes  of  cord,  563,  567,  569,  573 
Reid's  base  line,  47 
Renal  abscess,  381,  382,  384 

artery,  385,  391-392 

calculus,  387-388,  390,  410,  420 

colic,  386-387,  390 

plexus,  386-387,  392 

vessels,  385 
Resections.     See  Various  parts. 
Respiration  in  fracture  of  spine,  574 
Respiratory  wave  in  veins,  142 
Retention  of  urine,  423,  573-574 
Retroflexion  of  uterus,  433 
Retropharyngeal  abscess,  i26-127,  158 
Retroversion  of  uterus,  433 
Rhinoplasty,  81 
Rhinoscopy,  82 
Rhomboid  ligament,  169 
Ribs,  230 

cervical,  135 

counting  of,  229,  315 

excision  of,  231 

fractures  of,  231 

rudimentary,  12,  315,  381 
Rider's  line,  492 
Right  auricle,  253-256 

lymphatic  duct,  262 

ventricle,  253-256 
Rima  glottidis,  147 
Ring,  abdominal,  291,  292 

crural,  302-305,  492 
Robson's  line,  486 

Rolandic  points,  superior  and  inferior,  47 
Rolando,  fissure  of,  46-48 
Root  of  lung,  247,  249,  258 
Rosenmuller,  fossa  of,  65,  126,  128,  162 
Rouge's  operation,  81 
Round  ligaments,  432,  433,  441,  445 
course  of,  445,  446 
shortening  of,  300,  446 


Sacral  dimple,  268 
Sacrococcygeal  joint,  395 

tumors,  395,  396 
Sacro-iliac  joint,  396-398,  486 
abscess  of,  396 
disease  of,  396 
ligaments,  396,  397 
Sacrosciatic  ligaments,  395-396,  474,  485 
Sacrovertebral  angle,  25,  26,  395 


INDEX 


595 


Sacrum,  means  of  holding  it  in  place,  396- 
397 
promontory  of,  395 
wedse-shape  of,  396-397 
Sagittal  fontanelle,  2S 

suture,  26 
Salivary  fistula?,  99 
Saphenous  nerve,  external,  527,  528 

internal,  493,  508,  509,  514,  526, 
527 
opening,  305,  490,  492 
vein,  long,  490-493,    508,    509,    514, 
526,  527,  528,  529,  533,  542 
short,  514,  526-528,  533,  542 
Sartorius,  490,  493,  507,  508,  509 
Scalenus,  anterior,  132,  134 
Scalp,  18 

abscess  of,  23 

aponeurosis  of,  20 

arteries  of,  21 

bleeding  from,  22 

dangerous  area  of,  20 

fatty  tissue  in,  19 

hair  of,  19 

hematoma  of,  23 

incisions  in,  21 

lymphatics  of,  22 

mobility  of,  20 

nerves  of,  22 

neuralgia  of,  22 

pericranium  of,  20 

sebaceous  tumors  of,  19 

skin  of,  19 

subaponeurotic  areolar  layer  of,  20 

subcutaneous  tissue  of,  19 

suppuration  in,  20-23 

temporal  region  of,  24 

vascularity  of,  20 

-ils  of,  20 
wounds  of,  20,  22 
Scaphoid  bone,  209,  211,  534,   539,    540, 
546,  549 
fracture  of,  21") 
Scapula,  164,  172,  229,  554 
borders  of,  L6 I 
mii  of,  173 
fractures  of,  172 
tumors  of,  17:'. 
winged,  172 
Scapular  line,  229 

Scarpa's  triangle,  489,  490,  193,  608 
fascia  of,  191,  192 
landmarks  of,  190 
lymph  nodes  of,  190,  191,  194 

n  of.  189 
topography  of,  490 
1    of,  190,  193 
ioi    186,  l-ss 
nerve,  great,  104,  186   187,  189,  509, 
:,iii 
exposun 
pai 

•  tching  of,  187 
notch,  great,  I'M,  is:,  186,  606 

Scolii 


Scrotal  ligament,  467,  470 
Scrotum,  465 

blood  supply  of,  467 
dartos  of,  466 
development  of,  468 
in  edema,  466 
in  elephantiasis,  468 
layers  of,  465^67 
lymphatics  of,  468 
skin  of,  465 
Semilunar  cartilages  of  knee,  522 
dislocation  of,  522 
fold  of  Douglas,  275 
ganglia,  392 
line,  268,  274,  283 
Semimembranosus  tendon,  513,  515 
Seminal  vesicles,  410,  427,  429,  481 
position  of,  429-430 
relations  of,  429 
Semitendinosus  tendon,  513,  515 
Sensory  area  of  cortex,  44 

nerve  roots,  trophic  centres  of,  567 
Septum  crurale,  278,  304 

of  nose,  83 
Serratus  magnus,  172,  187 
Seventh  cranial  nerve,  66,  92,  102,  103 
Sheath  of  rectus,  274 
Shingles,  280-281 
Shoulder,  163 

anterior  region  of,  165 
bursa;  about,  175-176 
deltoid  region  of,  174 
dislocations  of,  176 

complications  in,  181-182 
mechanism  of,  177 
reduction  of,  180-181 
fractures  about,  182-184 
joint,  175 

amputation  at,  184 
disease  of,  176 
excision  of,  184 

muscles  strengthening  capsule, 
175 
posterior  region  of,  172 
surface  landmarks  of,  163 
topography  of,  1(15 
Sigmoid  flexure,  357 
Sinus,  cavernous,  39,  69 

great,  of  aorta,  257-258 
lateral,  course  of,  38 
sigmoid,  38 

course  of,  38 

relation  to  mastoid  antrum  and 

cells,  61,  <;:< 
sepl  io  thrombosis  of,  38 
superior  Longitudinal,  36 
Sinuses  of  dura,  36 

mechanism  to  pre^  enl  aspirai  ion 
ot.  :;■.) 
of  Valsah  a,  267 
Sixth  cranial  nerve,  77 

paralj  sis  of,  77 
cen  i<';il  vertebra,  1 29,  1 30,  I  io 
Skull,  26 

abnormahl ies  of,  is,  27 
blood    uppl]  of,  28 


596 


INDEX 


Skull,  buttresses  of,  29 
construction  of,  28 
deformities  of,  27 
development  of,  27 
elasticity  of,  30 
emissary  veins  of,  21 
of  female,  17 
fractures  of,  30 
base  of,  31 

mechanism  of,  32 
vault  of,  31 

symptoms  and  danger  of,  31 
growth  of,  18 
of  idiot,  17 
of  infant,  17 
necrosis  of,  28 
pericranium  of,  20 
racial  differences  of,  18 
soft  parts  covering,  18 
surface  landmarks  of,  25 
sutures  of,  26 
thickness  of,  28 
topography  of,  26 
trephining  of,  29 
veins  of  diploe  of,  22 
Small  intestine,  334 

occipital  nerve,  55 
Smell,  centre  of  sensation  of,  45 
Socia  parotidis,  98,  101 
Soft  palate,  128 
Solar  plexus,  260,  392 
Soleus,  526-528 
Spasmodic  stricture,  454 
Spastic  paralysis,  567 
Speech  areas  of  brain  cortex,  44-45 
Spermatic  artery,  472-474 

cord, 292-293,  304,  430,  472-474 
fascia,  external,  271,  291,  466 
plexus  of  veins,  474 
Sphenoidal  sinuses,  90 
Sphenomaxillary  fossa,  73,  89,  95-96 

fissure,  73,  78 
Sphincter  ani,  411,  416,  483-484 

of  bladder,  internal,  421,  428,  459 
Spina  bifida,  558,  559,  564 

occulta,  559 
Spinal  abscess,  556 

accessory  nerve,  131-132 
anesthesia,  560,  565 
canal,  558 
cord,  563 

anesthesia  due  to  injury  of,  569- 

572 
concussion  of,  566 
compression  of,  564,  566 
conduction  paths  of,  566 
contusion  of,  566 
defecation  in  injuries  of,  573 
enlargements  of,  563 
lesions  of,  569 

complete  transverse,  569 
level  of,  570 
partial  transverse,  569 
unilateral,  569 
localization  of    injury  of,   570- 
573 


Spinal   cord,  manner    of    suspension    in 
canal,  563,  564 
micturition  in  injuries  of,  573- 

574 
motor  paralysis  due  to  injury  of, 
569-574 
tracts  of,  566 
operations  on,  576 
recuperative  power  of,  569 
reflex  arc  of,  567 

motor  distribution  of, 

572,  573 
sensory  areas  of,  570, 
571 
respiration  in  injuries  of,  574 
segments  of,  570-574 

relations     of,     to     spinous 
processes,  571 
sensory  tracts  of,  566-567 
topography  of,  563 
tumors  of,  569,  576 
curvature,  227,  556-558 
dura,  564 
furrow,  312 

hemorrhage,  564-566,  574,  576 
meninges,  486,  563,  564 
meningitis,  564 
nerve-root  lesions,  571 
nerves,  points  of  origin  of,  570,  571 
reflexes,  563,  567,  569,  573,  574 
inhibition  of,  567 
Spine,  554 

caries  of,  311,  566 
curvature  of,  228,  556 
curves  of,  555,  556 
fractures  and  dislocations   of,   561- 
563,  566 
compression,  562 
tearing,  562 
functions  of,  554 
iliac,    anterior    and    posterior.     See 

Iliac, 
of  ischium,  395,  486 
laminectomy  of,  563,  569 
landmarks  of,  554 
movements  of,  555,  559 
of  scapula,  164,  246,  554 
sprains  of,  560 
topography  of,  554 
Spinous  processes,  fracture  of,  562 
Splanchnic  nerves,  260,  392 
Spleen,  375 

artery  of,  378 
displacement  of,  377 
enlargement  of,  377 
extirpation  of,  378 
held  in  position  by,  376 
injuries  of,  377 
percussion  of,  378 
position  of,  375 
relations  of,  378 
rupture  of,  377 
size  of,  377 
Splenectomy,  378 
Splenic  flexure,  356 
Spongy  portion  of  urethra,  455 


INDEX 


597 


Squamous  suture.  26 

bone,  descending  plate  of,  60 
Squamomastoid  suture,  60  62 
Btenson's  duct,  97  99 
course  of,  98 

Wollllds  of,  99 
Sternal  line,  22s 
Sternoclavicular  joint,  162,  169 
diseases  of,  I  70 
dislocations  of,  1 69 
Sternohyoid  muscle.  149,  L53   155 
Sternomastoid,  130-131,  L32,  1  10 

action  of,  131 

sheath  of,  130 

in  torticollis.  131,  132 
Sternoxiphoid  joinl .  22'.) 
Sternum,  229 

fractures  of,  230 

holes  in.  230 

operal ions  on.  230 
Stomach,  320,  323 

acute  dilatation  of,  337 

axis  of,  327 

cancer  of,  333 

curvatures  of,  32  I.  326 

ectasia  of,  325-326 

foreign  bodies  in.  32  I 

hernia  of.  333 

hour-glass  contraction  of.  325,  332 

lymphatics  of ,  161,  33 I-  332 

nerves  of,  332 

operations  on,  284,  327  329 

position  of,  325 

maintained  by,  330 

ptosis  oi .  326 

relation-  of,  330 

shape  of,  323.  321 

size  of,  32.". 

ulcer  of,  330,  332 
els  of,  331 

wall,  330 

wounds  of.  :;:; I 
Stomatitis,  113 
Strabismus,  75,  70.  77 
Si  r  i  *  - 1  ure.     ,s'<<  Various  parts. 
102.  L28,  101 

omaxillary  ligamenl .  99,  157 

cromial  bursa,  I  7.". 
Subarachnoid  fluid,  1 1 

space,  lo.  560,  56  I 
Subastragaloid  amputation,  549 

dislocal ion-.  .") is 

luricular  depression,  130 
Subclavian  arti  L34,     I :;."».     168, 

17:',,  211 
ligal  ion  of.  I ;;:; 

collateral    circulation    after, 

L35 
triangle,  132 
133    168 

1 1  is 
Subcoracoid  bursa;,  1 77 

dislocation,  177.  17s 
Subcrural  bui  ia,  522 
Subdeltoid  bursa,  I7."> 
Subdiaphragmatic  ab 


Subdural  space,  36,  564 
Subglenoid  dislocation,  1711 
Subhepatic  space.  372 
Subhyoid  region,  L38   L39 
Sublingual  artery,  L38 

bursa,  120 

gland,  119 
Submaxillary  gland,  135-137 
abscess  of.  137 

accessory  port  ion  of,  137 
lymph  nodes  of,  130,  160 
sheath  of,  136,  157 
triangle,  1 3"> 
Submental  lymph  nodes,  138,  160 
Subperitoneal  connective  tissue,  277,  107, 

419,  420,  131,    179 
Subpubic  angle,  394 

curve  of  urethra,  456-459 
Subscapular  artery,  173,  182,  188 
Subscapulars,  178,  18G 
Superficial  cervical  nerves,  132 

nodes,  160 
Superior  carotid  triangle,  139 

laryngeal  nerve,  lbs,  139,  144,  147, 

148-1  19 
longitudinal  sinus,  30 
maxilla,  104 

cleft  of,  122-123 
excision  of,  104-105 
fractures  of,  104 
how  held  in  position,  104 
necrosis   of,  103 
tumors  of,  10  1,  10."),  114 
thyroid  arler\',   130,  144 

vena  cava,  250,  2.~>7,  2(H) 
Supination,  200 
Supinators,  200-207 

Supraclav  ictilar  fossa,  132 

nerves,  132,  165 
Suprahyoid  region,  bio 
SupramarginaJ  gyrus,  50 
Supramastoid  eresl .  25 
Suprameatal  triangle,  61 
Supra-orbital  foramen,  73,  96 

margin,  73 

nerve,  78 
Suprapubic  cystotomy,  408,  1 19 

Suprarenal  bodies,  300 

oen  e  Bupply  of,  301 

relations  of,  390 

Suprascapular  artery,  133,  168,  L73  171 

nerve,  17  I 
Supraspinal  us,  170 

Sustentaculum  tali.  539,  546 
Sul  ure  membrane.  'JO 
Sutures  of  skull,  20 

closure  of,  27 

diastasis  of,  26 

posil  ion  of,  20 
Sylvian  point ,  is,  io 
Sylvius,  fissure  of,  is  50 
ion.  550 
Sympathetic  ner\e-,  abdominal.  392  393 

cer\  ical,  I  hi 

fund  ion  of,  I  13 
■ha  of,    I  13 


598 


INDEX 


Sympathetic  nerves,  cervical,  operation 
on,  144 

of  eye,  78 

thoracic,  pressure  on,  260 
Symphysiotomy,  397 
Symphysis  pubis,  394,  397,  494 
Synovial  cavities  of  foot,  549 

of  wrist,  214-215 
sheaths  of  ankle,  534 

of  fingers,  219-220 

of  palm,  219 

of  wrist,  210-211 
Syringomyelocele,  559 


Tabatiere  anatomique,  211 
Talipes  calcaneus,  547 
cavus,  543 
equinus,  546 
planus,  545-546 
valgus,  546 
varus,  547 
Tapping  the  abdomen,  319 
the  pericardium,  242,  252 
the  pleura,  232 
Tarsal  bones,  fractures  and  dislocations 
of,  549,  551 
cartilages,  67,  68,  70 
tumor,  70 
Tarsometatarsal  joints,  540 

amputation  through,  550 
Tarsus.     See  Foot. 
Taste,  centre  of  sensation  of,  45 
Taxis,  291,  295 
Tears,  passage  of,  72 
Teeth,  113 

enamel  of,  114 
eruption  of,  113 
Hutchinson's,  114 
Tegmen  antri,  61 
tympani,  60 
Temporal  abscess,  24 
artery,  21 
fascia,  24 
fossa,  24 
region,  24 
fat  in,  25 
fractures  in,  31 
Temporomandibular  articulation,  107 
ankylosis  of,  108 
dislocation  at,  108 
relations  of,  55 
Temporomaxillary  vein,  103 
Tendo  Achillis,  526,  528,  531,  533 
bursa  beneath,  535 
contracture  of,  534 
rupture  of,  528,  551 
tenotomy  of,  528,  533 
oculi,  66,  68,  71 
Tenon's  capsule,  73,  74,  79 

prolongations  of,  74 
Tenosynovitis,  211 
Tenotomy  of  hamstrings,  515 

external  popliteal  nerve  in,  515 


Tenotomy  of  sternomastoid,  131-132 
of  tendo  Achillis,  528,  533 
of  tibialis  anticus,  534 
posticus,  534 
Tensor  fasciae  latse  (vaginae  femoris),  486- 
487 
palati,  121 
Testis,  468 

attachment  of,  467,  468 
castration  of,  466,  472,  473 
consistence  of,  469 
descent  of,  294-295,  468 
development  of,  468 
ectopia  of,  469 
fetal  remains  of,  472 
hernia  of,  469,  470 
inversion  of,  468 
nerve  supply  of,  472 
position  of,  468 
retained,  469 
tunic  of,  470 
vessels  of,  471 
Tetanus,  109 
Tetany,  156 
Theca,  564 

Thenar  eminence,  215 
Thigh,  508 

amputation  of,  509,  511 
fasciae  of,  509 
fractures  of,  510,  511 
region  of,  508 
skin  of,  509 

surface  landmarks  of,  508 
topography  of,  508 
vessels  of,  509,  510 
Third  nerve,  68,  77 

paralysis  of,  77 
Thoracic  aneurysm,  257-259 
aorta,  259 

artery,  long,  165,  188,  237 
duct,  258,  259,  261,  264 
obstruction  of,  261 
wounds  of,  261 
nerve,  long,  172,  187 
nerves,  233,  272,  279-282,  392 
spine,  554,  558-560 
walls,  landmarks  of,  229 
layers  of,  229 
vessels  of,  232 
Thoracico-epigastric  vein,  279,  391 
Thoracotomy,  250 
Thorax,  226 

boundaries  of,  228 
deformities  of,  227,  228 
form  of,  226 
paracentesis  of,  232 
viscera  of,  241-265 
walls  of,  226 
Thrombophlebitis,  femoral,  494 
Thumb,  dislocation  of,  224 
Thymus,  remains  of,  244,  257 
Thyroglossal  duct,  116,  120,  152,  162 
Thvrohyoid  bursa,  144 

"  membrane,  129,  144-145,  148 
Thyroid  artery,  inferior,  154 

superior,  139,  144,  154 


INDEX 


599 


Thyroid  body,  130,  152 

accessory  portions  of,  152-153 

capsule  of,  153 

enlargement  of,  153,  154-155 

function  of,  15 1 

opera!  ions  on,  155 

position  of,  152 

pyramidal  lobe  of,  l">2 

relations  of,  153 
cartilage,  12'.t 

fracture  of,  I  Is 
isthmus,  149,  150,  152 

in  tracheotomy,  149,  150 
veins,  141,  150,  154 
Thyroidea  ima  artery,  150,  154,  259 
Thyrotomy,  148 
Tibia,  bordenTof,  525-526 

epiphvses'of,  524,  525,  538-539 
fractures  of,  525,  530,  537-539 
posterior  luxation  of,  515,  516 
in  rickets,  530 
strength  of  shaft  of,  529 
tubercle  of,  512,  519,  521,  531 
tulierosities  of,  512 
Tibia]  artery,  anterior,  526,  528,  531,  532, 

old 

posterior,  526,  528,  531,  532,  540 
bifurcation  of,  526,  533 
nerve,  anterior,  532 
posterior,  532,  543 
Tibialis  anticus,  526,  531,  534,  545 
tenotomy  of,  534-355 
posticus,  531,  532,  533,  545-546 
dislocation  of,  533-534 
tenotomy  of,  534 
Toe,  great,  amputation  of,  550 

'IMocation  of,  551 
Tongue,  114 

in  anesi  besia,  114 

blood  supply  'of,  HCi-117 

excision  or,  1 16-117 

held  in  place  by,  114,  1 15 

l\  mphatics  of,  117 

mucosa  of,  1 16 

nerve  supply  of,  118 

newgrowtns  of,  1 16,  117 

wounds  of,  117 
Tongue-tie,  115 
Tonsil,  Lingual,  l  L6 

chka'sor  pharyngeal,  65,  128 
Tonsils,  i_'i 

bleeding  iron,.  124   125 

blood  supply  of,   l-'.~> 

li\  perl  ropnj  of,  12.", 
with  deafness,  65 
L26 
position  of,  121   125 
llitis,  125 

124   I  25 

Torticollis,   [31    132 
M     130,   I  l!l 

bifurcation  of,  340,  L52 

diameter  of.   150    151 

I  It) 

foreign  bodies  in,  152,  251 
length  oi,  1 16 


Trachea,  mobility  of,  149 

relations  of,  149,  150,  258 

in  thorax,  250 
Tracheotomy,  148,  150-152 

in  children,  151 
Tracts  of  spinal  cord,  566 
Transversalis  fascia,  276-277,  292 

muscle,  272 

posterior  aponeurosis  of,  314 
Transverse  cervical  artery,  133 
nerves,  132 

colon,  320,  356 

diameter  of,  388 

facial  artery,  98 

process  of  atlas,  130,  554 

of  sixth  cervical  vertebra,  130 
Trapezius,  131-132 
Trapezium,  209 
Trapezoid  ligament,  170 
Treitz's  fossa,  337 
Trendelenburg's  position,  419 
Trephining,  29 
Triangle,  anterior,  of  neck,  135 

carotid,  139 

at  elbow,  194 

occiptial,  132 

of  Petit,  271,  313 

posterior,  of  neck,  132 

Scarpa's,  489,  490,  493,  508 

subclavian,  132 

submaxillary,  135 
Triangles  of  neck,  132-139 
Triangular  fascia,  274,  291 

fibrocartilage,  212 

ligament  of  urethra,  406,  449,  454, 
477-479 
Triceps,  198-199 
Tricuspid  valve,  position  of,  254 
Trigeminal  nerve,  78,  94-97 
Trigone,  410,  429,  447 
Trismus,  109,  119 

Trochanter,  great,  485, 486,  494-495,  501, 
504,  506 

bursas  over,  488 
Trophic  centres  of  spinal    nerve  roots, 

567 
Tubal  pregnancy,  442,  443 
Tube,  Eustachian,  63 

Fallopian,  442 
Tuber  ischii,  394,  395,  397,  475,  485,  488, 

no 
Tuberosity  of  fifth  metatarsal,  539 
fracture  of,  551 

of    humerus,  great,    Hi),  177,   178- 
179,  183 
l  i'j 
Tubo-ovarian  Ligament,  I  M),   1 12, 
Tunica  albuginea,  in,  170 

vaginalis,  167,  470 
turbinate  hone-.,  g i,  85 
Tympanic  membrane,  56 

opic  image  of,  56  ">7 
nipt  iin-  ol.  56,  57 
Tympanites,  319 
I  -.  mpanum,  58 

walls  ol,  59  60 


600 


INDEX 


Ulcer  of  duodenum,  336 
of  stomach,  330,  332 
Ulna,  204,  206 

dislocation  of,  201 
fracture  of,  206-207 
styloid  process  of,  208-209,  213 
Ulnar  artery,  205,  210 

nerve,  190,  191,  192,  195,  198,  205, 
208,  210,  220,  222 
paralysis  of,  222 
Umbilical  cord,  287 
fistula,  290 
hernia,  288-289 
region,  287 
Umbilicus,  268,  287 

fibrous  ring  of,  288 
position  of,  268 
vessels  of,  288 
Umbo  of  membranum  tympani,  56-59 
Upper  extremity,  163 

avulsion  of,  168 
Urachus,  289 
Ureter,  388 

calculi  of,  447 
catheterization  of,  447 
course  of,  388 
diameter  of,  388 
*  distention  of,  388 
in  female,  388,  447 
length  of,  388 
operations  on,  390 
position  of,  390 

relations  of,  388,  389,  429,  439,  443- 
444 
to  uterine  vessels,  388,  436,  438 
varieties  of,  389 
vesical  end  of,  420,  423 
Urethra,  female,  447,  450 
course  of,  450 
direction  of,  450 
external  meatus  of,  450 
sphincters  of,  450 
male,  452 

anterior,  457 
bulbous  portion  of,  455 
caliber  of,  457-458 
catheterization  of,  455,  460 
changes  according  to  age  of,  460 
curve  of,  456,  458-459 
direction  of,  456 
distensibility  of,  458 
divisions  of,  452 
external  meatus  of,  455 
fixed  portion  of,  456 
internal  meatus  of,  418,  423,  458 
length  of,  457-458 
membranous,  410,  454 
movable  portion  of,  456 
mucosa  of,  456 
narrowest  parts  of,  458 
posterior,  457 

prostatic,  426,  452-454,  458 
relations  of,  410,  477 
rupture  of,  460 


Urethra,  male,  sphincters  of,  459 
spongy  portion  of,  455 
stricture  of,  455,  459,  461 
Urethral  caruncle,  451 

triangle,  475 
Urethritis,  457,  461 
Uterine  artery,  436,  438 

fibroids,  437 
Utero-ovarian  ligament,  440,  441,  445 
Uterovesical  pouch,  424,  434 
Uterus,  431   - 

axis  of,  432 

development  of,  438 

displacements  of,  433,  434 

fixation  of,  432 

isthmus  of,  433 

ligaments  of,  432,  445 
lateral,  430,  444 
round,  430 

lymphatics  of,  438 

masculinus,  453 

operations  on,  438 

position  of,  432 

prolapse  of,  434,  447,  448 

relations  of,  409,  432,  434 

rupture  of,  437 

shape  and  size  of,  431 

vessels  of,  438 

wall  of,  437 
Uvula,  122 

vesicae,  424,  426 


Vagina,  447 

relations  of,  410,  445,  447,  448 

structure  of,  449,  450 

walls  of,  447,  448 
Vaginal  cystocele,  447 

examination,  395,  435,  448  ' 

fornices,  435,  448 

hernia,  405 

process,  294 

rectocele,  448 
Vaginismus,  448 
Vagus  nerve,  140,  143,  144,  250,  258,  259, 

392 
Valsalva's  method  of  inflating  middle  ear, 

64 
Valve,  ileocecal,  346 
Valves  of  heart,  position  of,  254 
Varicocele,  474 
Varicose  veins,  529 

Vas  deferens,  410,  420,  430,  431,  472-473 
artery  of,  431,  474 
position  and  relations  of,  430, 
431 
Vascular  compartment,  302 
Veins.     See  Various  parts. 

air  in,  133,  142,  159 

of  diploe,  22 

emissary,  of  skull,  21 
Velum  pendulum  palati,  121 
Vena  cava,  inferior,  362,   371,   373,   380, 
389 


INDEX 


li()l 


Vena  cava,  superior,  250,  256,  2">x,  260 

Vena  ports,  321,  364,  365 
section  at  elbow,  L96 

Ventricles  of  heart.  253-256 
of  larynx.  1  46 
lateral,  of  brain,  50,  51 

Vermiform  appendix,  3  18 
direct  inn  of,  350 
fecal  concrel ions  in,  :'>•">  1 
length  and  lumen  of,  •'!  Is.  3  19 
mesentery  of,  3  19 
position  of,  344,  345,  350 
relations  of,  344,  345,  350 
vessels  of,  352 
wall  of,  3.">1 

Vermilion  border  of  lips,  1 10 

Vertebra,  caries  of,  31 1,  556 
prominens,  L30,  55  I 

Vertebral  artery.  1 40 
column,  55  I 

Verumontanum,  428,  153 

prostatic  plexus.  122,  127    128 

Vesicopubic  muscle,  406 

Vesicovaginal  fistula,  121.  117 

VesicuUe  seminales,  no.  127.  129,  481 
capsule  of.  129 
operations  <>n.  130,  181 
position  mi.  n>'.i    130 
relations  of,  429 

Vestibule  of  mouth,  1  L2 

Viscera]  arches,  161-162 

clefts,   llil-162 
Visual  center  of  cortea  .    15 
Visuopsychic  cenl  re,  i."> 
Vitellme  duct.  288 
Vocal  cords,  l  16  l  is 
Volvulus,  357 
Vomiting,  56,  334 
Vulva,  151 
Vulvovaginal  abscess,  452 

gland,  152 


W 


W  urdrop's  operation,  139 
Weaver's  bottom,  188 
"Weeping  sinew,"  212 
Wharton's  duct,  119,  137 

White  line  at  anus,  411 

in  pelvic  fascia.  106,  183 
Whitlow,  222 
Willis,  circle  of,  140 
W  olffian  tubules,  111.  172 
Wormian  hones,  27 
Wrist-drop,  192 
\\  list  joint,  212 

amputation  al  .211 
dislocations  at,  212 
epiphyseal  separation  at,  214 
excision  of,  214 
fractures  about,  213-214 
movements  of,  212 
region  of,  208 
skin  creases  of,  209 
surface  landmarks  of,  208-209 
tendons  about,  209-211 

synovia]  sheaths  of,  210,  21 1 
topography  of,  209 
Win -neck,   131,  132 


Y-i.h;a.\ii-;\t.     See  Iliofemoral  hand. 
Y-shaped  cartilage  of  acetabulum,  195 


Zl  CKERKANDL's  perineal  incision.    isl 
Zygoma,  21,  61,  98,  99,  102 
Zygomatic  fossa,  73,  99,  107 


>olse; 


Qw 


W8R 
1908 


Applied  surgical  anatomy 


;.;■•-:■;:;.,. 


WBBWW1WB 


